Fabrication, Characterization, and In Vivo Evaluation of

Research ArticleFabrication Characterization and In Vivo Evaluation ofFamotidine Loaded Solid Lipid Nanoparticles for BoostingOral Bioavailability

Muhammad Shafique12 Mir Azam Khan1 Waheed S Khan23 Maqsood-ur-Rehman12

Waqar Ahmad1 and Shahzeb Khan1

1Department of Pharmacy University of Malakand Chakdara Dir (L) Khyber Pakhtunkhwa 18800 Pakistan2Nano-Biotech Group National Institute for Biotechnology and Genetic Engineering Faisalabad 38000 Pakistan3Ningbo Institute of Materials Technology and Engineering (NIMTE) Chinese Academy of Sciences (CAS) Ningbo Zhejiang China

Correspondence should be addressed to Mir Azam Khan mirazam786yahoocom

Received 31 July 2017 Revised 14 November 2017 Accepted 20 November 2017 Published 14 December 2017

Academic Editor Mohamed Bououdina

Copyright copy 2017 Muhammad Shafique et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

Famotidine as H2receptor has antagonistic effects on gastric secretion Unfortunately its hydrophobic nature contributes to

its variable and poor oral bioavailability In the current study efforts are being made to fabricate famotidine loaded solid lipidnanoparticles with narrow size distribution Prepared nanoformulations were pharmaceutically evaluated to confirm the desiredboosted oral bioavailability Famotidine loaded nanoformulation (FFSe-4) showed particle size 1119plusmn13 nm polydispersity index0464 plusmn 003 zeta potential minus3346 plusmn 2mV entrapment efficiency 84 plusmn 27 and drug loading capacity 2709 plusmn 013 Drug-excipients compatibility was confirmed by Fourier transformed infrared spectroscopy Scanning electron microscopy confirmedspherical shaped nanosized particles Differential scanning calorimetry and powder X-ray diffractometry confirmed the change incrystalline nature Prepared nanoformulation was more stable at refrigerated temperature In vitro study showed that drug releasetime is proportional to drug pay load and followed zero order kinetics Release exponent (119899 gt 05) confirmed non-Fickian-diffusionmechanism for drug release In vivo pharmacokinetic studies showed 206-fold increase in oral bioavailability of famotidinedispersed in solid lipid nanoparticles compared to commercial productThese results authenticate solid lipid nanoparticles as drugdelivery system and propose prolonged release with improved oral bioavailability for famotidine

1 Introduction

Approximately 40 of commercialized active pharmaceuti-cal ingredients (APIs) are poorly water soluble due to whichsufficient amount of drug absorption from the gastrointesti-nal tract (GIT) is being a challenge for the researchers [1]Low solubility and permeability lead to oral bioavailabilityissues which ultimately affect the drug safety and efficacy[2] Previously different colloidal carrier systems have beeninvestigated to overcome this problem But certain disadvan-tages were associated with them such as drug expulsion uponstorage limited stability low drug loading and polymerscytotoxicity [3]

This leads to the rise of fabricating solid lipid basednanodrug delivery system termed as solid lipid nanoparticle

Solid lipid nanoparticles (SLNs) were developed in the endof the 20th century [4] It potentially gathers pluses of theold systems but avoids some of their major documentedshortcomings [5] The use of SLNs is a striking improvementbecause the solid matrix of the lipids presents high flexibilityin controlling the drug release and protects the encapsulateddrugs fromgastric degradation SLNs are generally composedof biodegradable and biocompatible solid lipid as solid corecoated by nonhazardous surfactantcosurfactant as the outershell [6] Use of solid lipids increases drug absorption mainlythrough enhanced drug dissolution and solubilization in theintestinal-milieu improved lymphatic-transport enhancedgastrointestinal permeability and decreased gastric-empty-ing rate [7 8] Particle size and PDI are key characteristics

HindawiJournal of NanomaterialsVolume 2017 Article ID 7357150 10 pageshttpsdoiorg10115520177357150

2 Journal of Nanomaterials

S

NS N

SOO

N（2

（2

（2

（2

Figure 1 Chemical structure of famotidine

and are critical parameters in the stability and fabrication ofSLNs [9]These characteristics mainly depend upon particlescomposition and different fabrication techniques

Famotidine is widely used as competitive H2receptor

antagonist (H2RA) and prokinetic drug [10] Molecular

formula of famotidine is C8H15N7O2S3and IUPAC name

is 3-[[2-(diaminomethylideneamino)-13-thiazol-4-yl]meth-ylsulfanyl]-N1015840 sulfamoylpropanimidamide (Figure 1) Its keypharmacodynamic effect is the inhibition of gastric acidsecretion [11] It decreases stomach acid production up to 90when given in oral dosage form (20mg or 40mg) and pro-motes duodenal ulcer curing [12] It is used in the treatmentof heart-burn ulcer and inflammation of esophagus and highdoses are used for the treatment of conditions like Zollinger-Ellison syndrome It is commercially available in differentdosage forms like capsules tablets and also chewable tabletsfor adults Powder was also prepared for oral suspension butafter reconstitution its stability was limited to thirty days onlyand also had extremely bitter taste [12] Hence researchersalso tried numerous techniques to mask its bitter taste [13]Hydrophobic nature of famotidine reduces its water solubilityand also exposure to gastric degradation contributes to itsvariable and poor oral bioavailability [14]

Famotidine belongs to Class-IV drugs of biopharmaceu-tical classification system (BCS-IV) Drugs of this class showpoor aqueous solubility and low permeability [15] Due towhich its oral formulations have not been successful dueto low water solubility issues (11mgsdotmlminus1) and unfavorablepharmacokinetic parameters including low oral bioavail-ability (43) and a short plasma half-life (259 hrs) [16ndash18] Before selecting famotidine as drug model for loadinginto SLNs the available limited literature for addressing theoral bioavailability issues has been studied Patel DhavalJ et al 2010 have reported FTD nanosuspension havingminimum particle size of only 566 nm and also lackingstability study Also there has not been reported any in vivopharmacokinetic study

This research work was carried out to fabricate FTDloaded SLNs to enhance its aqueous solubility which in turnboost its oral bioavailability SLNs were fabricated by solventemulsification evaporation technique which is most suitablefor of thermosensitive drugs as it avoids thermal stress[19] SLNs have adhesive properties that could increase theresidence time in the administered area and hence enhanceits oral bioavailability [20] The use of tween-80 as surfactantandPVP as cosurfactantmay also improve oral bioavailabilityas they contribute to enhancing permeability aswell as affinitybetween lipids and intestinal membrane [21 22]

Table 1 Formulations of unloaded SLNs

Formulation Stearic acid(g)

Tween-80(ml)

PVP(g)

Stirring time(min)

UFSe-1 100 05 Nil 5UFSe-2 100 1 Nil 5UFSe-3 100 15 Nil 5UFSe-4 100 2 Nil 5UFSe-5 100 19 01 5UFSe-6 100 18 02 5UFSe-7 100 17 03 5UFSe-8 100 16 04 5UFSe-9 100 15 05 5UFSe-10 100 16 04 10UFSe-11 100 16 04 15UFSe-12 100 16 04 20PVP polyvinyl pyrrolidone

2 Materials and Methods

21 Materials Famotidine was procured as generous giftfrom Polyfine Chempharma (Pvt) Ltd (Peshawar Pakistan)Stearic acid and tween-80 were got from Acros OrganicsThermo Fisher Scientific New Jersey USA Polyvinylpyrroli-done (PVP-K30) was got from Crescent Chemical CompanyIslandia New York USA Dialysis bags were obtained fromSpectrum labCanada Remainingmaterials were of analyticalgrade or equivalent

22 Methods

221 Preparation of Unloaded SLNs Unloaded SLNs werefabricated by solvent emulsification evaporation (SEE) tech-nique using different surfactant (tween-80) concentrationcosurfactant (PVP) concentration and stirring time (Table 1)[19] Specified amount of stearic acid was dissolved inchloroform which was then emulsified with aqueous phasehaving surfactant (Tween-80) and cosurfactant (PVP) undermagnetic stirring (1000 rpm) to form microemulsion Inthis microemulsion aqueous phase contains micron-sizedroplets of organic solvent containing stearic acid Organicsolvent is evaporated from this microemulsion via magneticstirring As the organic solvent evaporates the lipid startsprecipitating as SLNs in the aqueous phase is followedby centrifugation using ultra-centrifuge Cs 150 GXL (Gx-Series) for 10 minutes at 30000 rpm [23] 119885-average particlesize and PDI of these formulations were figured out byphoton correlation spectroscopy using zeta-sizer Nano (ZS-90 Malvern Instruments Malvern UK) [24]

222 Preparation of FTD-SLNs Best conditions of UFSe-11formulation that is stearic acid (10 g) tween-80 (16ml)and PVP (04 g) were further used for fabricating FTDloaded SLNs (FTD-SLNs) Different formulations of FTD-SLNs were prepared on the basis of lipid drug ratio (Table 2)Specified quantity of FTD and stearic acid was dissolved in

Journal of Nanomaterials 3

Chloroform

Famotidine Stearic acid

Chloroform containing stearic acidand famotidine was agitated

Tween-80 Polyvinylpyrrolidone

Phosphate buffer solution

Phosphate buffer solution containing Tween-80 and polyvinylpyrrolidone was agitated

Organic phase was emulsified with the aqueous phase along with stirring

Heat before emulsion to evaporate chloroform to yield SLNs dispersion

Ultra-centrifugation

Solid lipid nanoparticles

Figure 2 Schematic diagram of solvent emulsification evaporation technique

Table 2 Formulations of FTD-SLNs


FTD(mg)

Tween-80(ml)

PVP(g)

Stirring time(min)

FFSe-1 100 40 16 04 15FFSe-2 100 50 16 04 15FFSe-3 100 666 16 04 15FFSe-4 100 100 16 04 15FFSe-5 100 200 16 04 15FTD famotidine PVP polyvinyl pyrrolidone

chloroformThe rest of process followed was same as adoptedfor unloaded SLNs Schematic diagram for preparation ofFTD-SLN is shown (Figure 2)

223 Lyophilization SLNs are thermodynamically insecuresystems therefore FTD-SLNs were lyophilized using freezedryer (Heto Power Dry LL1500- Thermo Electron Corpora-tion USA) Glucose solution (10) was added as cryoprotec-tant before drying FTD-SLNs were kept overnight at minus20∘Cand then shifted to freeze dryer to be lyophilized at minus75∘C for48 hrs at increasing rate of 5∘Ch [25]

224 Entrapment Efficiency (EE) and Drug Loading Capacity(DLC) Freshly fabricated FTD-SLNs samples were cen-trifuged and supernatants were analyzed to quantify unen-trapped drug using nanodrop spectrophotometer (Thermoscientific 2000c2000 UV-VIS Spectrophotometer)

Entrapment efficiency of FTD was calculated by

EE

=Total amount of drug added minus Unloaded Drug times 100

Total amount of drug added

(1)

Percent drug loading capacity of FTD was calculated by

DLC =Total amount of drug (SLNs) times 100

Amount of Drug + Amount of Excipients (2)

23 Characterization

231 Dynamic Light Scattering Zeta-sizer analysis was car-ried out by using zeta-sizer ZS-90 (Malvern InstrumentsEngland) 119885-average particle size PDI and zeta potentialwere analyzed All SLN formulations were diluted withdeionized water in order to get proper scattering intensitymeasured at 90∘ scattering angle and 25∘C

232 Drug-Excipients Interaction Fourier transform infra-red spectroscopy (IR Prestige 21 Shimadzu Japan) was usedto study drug-excipients interaction with diffuse reflectanceprinciple [26] Spectra of unprocessed FTD and processedFTD (FFSe-4) were scanned over a frequency range of 2000to 400 cmminus1 For compatibility of formulation componentsthe peaks and patterns shaped by the unprocessed FTD werecompared with processed FTD (FFSe-4)

233 Morphological Study Scanning electron microscopy(SEM) was used to study the morphological characteristicsand texture of SLNs by JSM5910 (JEOL Japan) [27] SEMmicrographs were recorded at magnification of 60000x andaccelerating voltage of 20 kV [28]

234 Powder X-Ray Diffraction (P-XRD) Powder X-raydiffraction analysis was performed to verify new solid stateformation [29] P-XRD analysis was conducted for unpro-cessed FTD and processed FTD (FFSe-4) using an X-raydiffractometer JDX-3532 (JEOL Japan) Cu K120572 radiation inscanning range of 2120579 = 5∘ndash80∘ was used with tube current30mA operated voltage of 40 kV step time 10 sec step size


005∘ divergence slit 1 degree scattering slit 10 degree andreceiving slit 02mm for measurement

235 Thermal Analysis Differential scanning calorimetry(DSC) is thermoanalytical method used to investigate melt-ing and recrystallization behavior of samples Accuratelyweighted unprocessed FTD stearic acid their physical mix-ture and processed FTD (FFSe-4) were analyzed by differ-ential scanning calorimeter (DSC) (Perkin Elmer DiamondSeries DSC Equipment-USA) Analyses were carried out incrimped aluminum pans at heating rate of 10∘Cmin from40ndash300∘C [30]

24 Stability Study Stability study was conducted at varioustemperatures in terms of measurement of particle size andPDI with respect to time

To examine the physical stability of FTD-SLNs stabilitystudy was carried out for FFSe-4 formulation [31]The freshlyfabricated sample was divided into two parts Each part wasput in two plain sealed glass vials and stored at differenttemperatures (5 plusmn 2∘C and 25 plusmn 3∘C) for 3 months Sampleswere taken on 1st 15th 30th 60th and 90th day of storageand subjected to particle size and PDI measurements Datawas analyzed statistically by two tailed 119905-test Probability lt005 was considered significant

25 In Vitro Release of FTD from SLNs In vitro drug releasestudy was conducted using dialysis bag method [32] Dialysisbags were soaked in deionized water for 12 hours beforeuse FTD-SLNs dispersion (1ml) from each formulation waspoured into the dialysis bag and placed in 250ml phosphatebuffer solution (pH 74) at 50 rpm After definite time interval(1ndash12 hr) samples were taken and equal volume of phosphatebuffer solution was replaced Samples were analyzed byusing UV spectrophotometer (120582max 265 nm) against blankphosphate buffer solution (pH 74) [33] Data obtained fromin vitro drug release study was fitted into different kineticmodels to find out both drug release rate andmechanism thatfollowed [34]

26 In Vivo Pharmacokinetic Studies

261 Oral Drug Administration Before conducting in vivostudy approval was taken from departmental research ethicscommittee (vide letter number DREC20160503-14) Healthyrabbits (2 plusmn 03Kg) were kept fasted (12 hrs) before dosingbut access to water was given Two groups of animalswere made each having six rabbits FFSe-4 formulationwas orally administered to Group I while Ricer to GroupII (10mgsdotkgminus1) At various time intervals (0 to 24 hrs)blood samples (05ml) were collected and kept in tubes(heparinized) Plasma was separated by centrifugation andstored at minus20∘C till further analysis

262 Quantification of Plasma Concentration Preparedplasma samples were analyzed for drug quantificationby HPLC technique Acetonitrile Methanol (0016moll)Phosphoric Acid (10 10 80) were used as mobile phase(retention time 3min flow rate 1mlmin) Reversed phase

column (Supelco C18 25 cm in length 46mm width and

5 120583mparticle size) generally used for hydrophobic drugs andprecolumn (Supelco C

18) were used at 37∘C Prior to HPLC

analysis plasma samples were mixed with acetonitrile andthen placed at minus20∘C for 10 minutes followed by centrifuga-tion to precipitate proteins The supernatant (20120583l) was theninjected for the determination of FTD concentration usingUV detector at 120582max 254 nm [33] Famotidine concentrationwas determined from the area of chromatographic peak usingthe calibration curve

263 Data Analysis Different pharmacokinetic parameterswere determined for non-compartmental model Area undercurve (AUC

0rarr119905) was calculated from concentration-time

curve by trapezoidal rule From the individual plasmaconcentration-time curve peak plasma concentration (119862max)and peak plasma concentration time (119879max) were calculatedTotal area under the curve (AUC

0rarr24) was determined by

AUC0rarr24= AUC

0rarr24+119862119905

119870119890

(3)

119862119905is FTD concentration at 24th hour and 119870

119890is apparent

elimination rate constantRelative bioavailability (119865

119903) after 24 hours for equal dose

was determined by

119865119903=

AUC-FFSe-40rarr24

AUC-Marketed product0rarr24

(4)

One-way analysis of variance and 119905-test (119901 lt 005) wereused for statistical analysis of data

3 Results

31 Dynamic Light Scattering Unloaded SLNs were fabri-cated on the basis of three variable factors that is surfac-tant concentration cosurfactant concentration andmagneticstirring time Significant changes were observed by changingthese three variables (Figure 3) Best unloaded formulationwasUFSe-11 having 119911-average particle size 1278plusmn23 nmandPDI 0485plusmn0001 Best drug loaded formulation was FFSe-4having 119911-average particle size 1119plusmn13 nm PDI 0464plusmn003and zeta potential minus3346 plusmn 2mV (Figures 4 and 5)

32 Entrapment Efficiency and Drug Loading CapacityEntrapment efficiency anddrug loading capacity observed forFFSe-1 formulation were 96 plusmn 29 and 1263 plusmn 013 whilefor FFSe-5 formulation they were 59 plusmn 317 and 3375 plusmn018 respectively The selected best formulation (FFSe-4)gave entrapment efficiency and drug loading capacity 84 plusmn27 and 2709 plusmn 013 respectively (Figure 6)

33 Drug-Excipients Interaction Fourier transform infraredanalysis is used specifically for assessing drug-excipientsinteraction in different formulations [35] The major peaksof C=C stretch at 1639 cmminus1 SO

2stretch peak at 1147 cmminus1

C-H bend at 1284 cmminus1 C=S stretch at 1146 and N-H bendat 984 cmminus1 were present in both unprocessed FTD and


04080120160200

0010203040506070809

1

Zeta

size

Poly

disp

ersit

yin

dex

(PD

I)

Formulations

Particle size and PDI of unloaded SLNs

SIZEPDI

UFS

e-1

UFS

e-2

UFS

e-3

UFS

e-4

UFS

e-5

UFS

e-6

UFS

e-7

UFS

e-8

UFS

e-9

UFS

e-10

UFS

e-11

UFS

e-12

Figure 3 Particle size and PDI of unloaded SLNs formulations

0

5

10

15

20

()

Size (nm)

Number distribution data ()

10E + 0410E + 0310E + 0210E + 0110E + 0010E minus 01

Figure 4 Particle size of FFSe-4

processed FTD (FFSe-4)This clearly indicates no interactionbetween FTD and other excipients The obtained spectra areshown (Figure 7)

34 Scanning Electron Microscopy (SEM) Shape and surfacemorphology of FFSe-4 formulationwas studied by SEM SEManalysis showed solid and fairly spherical shaped particleswith well-defined periphery The particles size was also innanometric range (Figure 8)

35 Powered X-RayDiffraction (P-XRD) Unprocessed famo-tidine (FTD) showed a series of sharp peaks indicatingits crystalline nature In processed FTD (FFSe-4) most ofthese peaks were suppressed but few disappeared indicatingconversion to amorphous form (Figure 9)

36 Thermal Analysis DSC thermograms of FTD (unpro-cessed) stearic acid (SA) physical mixture and processedFTD (FFSe-4) were recorded separately Sharp endothermicpeak was observed for unprocessed FTD at 1669∘C SAat 69∘C and physical mixture of FTD and SA at 1665∘Cand 686∘C respectively Processed FTD (FFSe-4) showedendothermic peak at 160∘C (Figure 10)

37 Stability Study Processed FTD (FFSe-4) sample showedno significant change in particle size and PDI stored atrefrigerated temperature (5 plusmn 2∘C) Increase in particle size

0

50000

100000

150000

200000

250000

minus200 minus100 0 100 200

Tota

l cou

nts

Zeta potential (mv)

Zeta distribution data

Figure 5 Zeta Potential of FFSe-4

0051152253354

020406080

100120

FFSe-1 FFSe-2 FFSe-3 FFSe-4 FFSe-5

Dru

g lo

adin

g ca

paci

ty (

)

Entr

apm

ent e

ffici

ency

()

Formulations

EE () and DLC () of FTD-SLNs

EE ()DLC ()

Figure 6 EE () andDLC () of different FTD-SLNs formulations

1639

1284

1147

984

(A)

(B)16

14

12

10

8

6

2000 1800 1600 1400 1200 1000 800 600 400

(1cm)

T

Figure 7 FT-IR spectra of unprocessed FTD (A) and processedFTD (FFSe-4) (B)

Figure 8 SEM micrograph of FFSe-4 formulation


0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta

P-XRD of unprocessed FTD and processed FTD (FFSe-4)

FamotidineFFSe-4

Figure 9 P-XRDof unprocessed FTD and processed FTD (FFSe-4)

(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature

Figure 10 DSC of unprocessed FTD (A) stearic acid (B) physicalmixture (C) and processed FTD (FFSe-4) (D)

Table 3 Cumulative percent release of FTD

S No Time(hrs)

Cumulative drug released ()FFSe-1 FFSe-2 FFSe-3 FFSe-4 FFSe-5

1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194

at refrigerated temperature was less than 5 but at roomtemperature it was almost 1591 At both temperatures theparticles growth was in acceptable range but PDI at roomtemperature exceeded the acceptable range (Figures 11 and12) Statistically analyzed data from two tailed 119905-test showed119901 value for particle size was 0044 and PDI was 0046

38 In Vitro Release of FTD from SLNS During 12 hr invitro drug release study cumulative percent drug release fromFFSe-1 to FFSe-5 formulations was 9921 9412 88317887 and 7194 respectively (Table 3 and Figure 13) FTD

0

50

100

150

1st 15th 30th 60th 90thTime (days)

Size (nm) at Refrigerator temperatureSize (nm) at room temperature

Size

(nm

)

Figure 11 Particle size during stability study

001020304050607


PDI at refrigerator temperaturePDI at room temperature

Poly

disp

ersit

y in

dex

(PD

I)

Figure 12 PDI during stability study

release time from SLNs was directly proportional to drugpay load [23] Further evaluation by putting the drug releasedata into different kinetic models showed that FTD loadedSLNs formulations followed zero order release kinetics with1198772 values in the range of 0958ndash0993 [36] However inKorsmeyer-Peppas model release exponent was greater than05 (119899 gt 05) confirming non-Fickian diffusion kinetics for allformulations (Table 4) [37 38]

39 In Vivo Pharmacokinetic Study The plasma concentra-tion-time curve of FFSe-4 formulation andmarketed productis shown (Figure 14) andpharmacokinetic parameters are alsolisted (Table 5) FTDplasma concentrationswere significantlyhigher in rabbits treated with FFSe-4 than for those treatedwith marketed product

Peak plasma concentration (119862max) for marketed prod-uct and FFSe-4 formulation was 0498 plusmn 014 120583gsdotmlminus1and 103 plusmn 0204 120583gsdotmlminus1 respectively AUC

0rarr24for mar-

keted product was 4396 120583gsdothrsdotmlminus1 whereas for FFSe-4was 23122120583gsdothrsdotmlminus1 FFSe-4 formulation showed 206-fold increase in 119862max and 525-fold increase in AUC

0rarr24

compared to marketed product These results showed thatFTD absorption was improved significantly in SLNs formu-lation compared with conventional dosage form (marketedproduct)

310 Discussion Solvent emulsification evaporation (SEE)method has been used to fabricate FTD loaded SLNs Opti-mized conditions for unloaded SLNs were stearic acid (10 g)


Table 4 1198772 value of different kinetic models for FTD-SLNs formulation

Formulations Zero order (1198772) First order (1198772) Higuchi model (1198772) Korsmeyer-Peppas modelRelease exponent (119899) (1198772)

FFSe-1 0958 0866 0966 082067309 0978FFSe-2 0973 0960 0955 089488353 0965FFSe-3 0981 0976 0956 089479258 0962FFSe-4 0991 0985 0950 093489612 0947FFSe-5 0993 0989 0949 094189608 0940

Table 5 Pharmacokinetic parameters of FFSe-4 formulation andmarketed product

Parameters FFSe-4 formulation Marketed product119862max (120583gmlminus1) 103 plusmn 0204 0498 plusmn 014

119879max (h) 12 plusmn 02 2 plusmn 03

AUC (120583gsdothrsdotmlminus1) 23122 plusmn 0003 4396 plusmn 0021

119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5

Figure 13 Drug release from different FTD-SLNs formulations

Tween-80 (16ml) PVP (04 g) and magnetic stirring time(15 minutes) (Table 1) 119885-average particle size was reducedby increasing surfactant concentration (Tween-80) its higherconcentration also gave better stability to small lipid dropletswhich prevent them from coalescence [39] Addition ofcosurfactant (PVP) further reduced 119911-average particle sizeas SLNs fabricated with surfactantcosurfactant mixture havelower 119911-average particle size and better stability PDI has beencontrolled and reduced by increasing magnetic stirring timeas it has almost no effect on particle size reduction but only onPDI [40] The optimized unloaded SLNs formulation (UFSe-11) showed particle size 1278 plusmn 23 nm After drug (FTD)loading the particle size was reduced to 1119plusmn13 nm (FFSe-4) having PDI 0464 plusmn 003 After drug pay load particlesize reduced due to decreased free lipid content [41] Zetapotential of FFSe-4 formulation was minus3346plusmn2mV sufficientfor electrostatic stability [42]

The PDI lt 05 and zeta potential plusmn 30 revealed that thefabricated nanodispersion would be stable in nature [43]

0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)

Drug release of FTD-SLNs (FFSe-4)versus marketed product

FFSe-4Marketed product

Con

cent

ratio

n (

g)

Figure 14 In vivo drug release from FFSe-4 formulation versusmarketed product

Both of these values for FTD-SLNs were within the rangeexhibiting electrostatic stabilization having no aggregationwhich led to preventingOstwald ripening andparticle growth[42]

The formulation (FFSe-4) gave entrapment efficiencyand drug loading capacity 84 plusmn 27 and 2709 plusmn 013respectively with maximum encapsulation and higher drugloading efficiency It has been reported that in polymerand lipid based nanoparticulate drug delivery systems thebinding energy of the drugs with the polymers and lipidsplays a key role in successful encapsulation of drugs [44] Inthis case it might be attributed to the high binding energy ofthe FTD with stearic acid tween-80 and PVP which resultsin maximum entrapment efficacy and drug loading capacity

However EE decreased from 96 to 59 as FTD payload increased from 40mg (FFSe-1) to 200mg (FFSe-5)This sudden fall in EE might be due to loading of FTDbeyond saturation level of lipid [23] Lipophilic drugs cangain super-saturation in melted lipids on cooling saturationlevel reduces and excessive quantity of drug tends to partitionin outer shell or external solvent [5]

FT-IR spectra of unprocessed FTD and processed FTD(FFSe-4 formulation) confirm the compatibility of FTD withthe formulation components (Figure 7) Scanning electronmicroscopy further confirmed nanometric size particles ofSLNs loaded with FTD Micrograph of SEM (Figure 8)shows solid identical and fairly spherical shaped particleswith a well-defined periphery Most of the SLNs are presentin dispersed form with homogeneous distribution whichexhibit amorphous nature of the produced nanoparticles P-XRD studies also confirmed the amorphous nature of the


FTD loaded SLNs as the disappearance and reduction inintensities of the peaks are indicative for amorphous natureof the particles (Figure 9) [43 45] DSC studies confirmedthe amorphous nature of the FTD loaded SLNs becausefor unprocessed FTD sharp melting point peak appearedon 1666∘C while for FTD loaded SLNs formulation it was160∘C (Figure 10)This small diffused peak indicated reducedparticle size of FTD enlarged surface area and closed contactbetween solid lipid (stearic acid) and drug (FTD)which couldbe considered for the change of FTD from crystalline toamorphous state [46 47]

In comparison with room temperature refrigerated tem-perature was best for the stability of FFSe-4 formulationThree-month study showed no significant change in size andPDI of the sample when stored at refrigerated temperature(Figure 11) However at room temperature some growth wasobserved for the initial 30 days which is because of theamorphous nature of the FTD-SLNs followed by stabilizationfor rest of the period Additionally at room temperatureamorphous solids have increased free energy which resultsin decreased stability [48 49]

In vitro study showed that increased payload of FTDresulted in prolonged drug release time (Figure 13) [23]Release of FTD from SLNs followed zero order kineticsHowever Korsmeyer-Peppas model showed that the releaseexponent (119899) was greater than 05 which confirmed non-Fickian diffusion kinetics for all SLNs formulations [37 38]

The interesting results obtained from statistically ana-lyzed data of in vivo pharmacokinetics confirmed boostedoral bioavailability with sustained release profile of FTD-SLNs (FFSe-4) compared to marketed product (Table 5)SLNs as drug delivery system open angles to formulatealready available drugs (BCS-II and BCS-IV) in the marketto boost their oral bioavailability and attain sustained releasebehavior SLNs are not only responsible for improvementof oral absorption but can correspondingly be formulatedfor parenteral administration which need additional studies[50]

4 Conclusion

This researchwork concluded that various processing param-eters are the characteristic key factors to prepare appropriatelipid carriers for efficient loading of the selected drug SLNshave been surfaced as novel drug carriers for famotidinewith boosted oral bioavailability and strong sustained drugrelease performance We have exposed that famotidine inform of SLNs is an encouraging nanomedicine with value-added physical stability and prolonged release profile Alsothere was good affinity found between famotidine and stearicacid In vitro and in vivo release study confirmed that SLNssystem is very suitable to improve oral delivery of poorwater soluble drug like famotidine with increased solubilityand permeability which in turn enhanced bioavailability Infuture perspectives the produced FTD loaded SLNs couldpotentially be transformed into solid dosage form followedby in vitro and in vivo assessments

Thus it is concluded that sustained release FTD-SLNswere successfully fabricated by simple and reproducible tech-nique (solvent emulsification-evaporation method) whichhas potential to be scaled up for commercial production andno sophisticated instrument is required during fabrication

Conflicts of Interest

The authors report no conflicts of interest in this research

Acknowledgments

The authors would like to acknowledge PolyfineChempharma (Pvt) Ltd (Peshawar-Pakistan) for providinggenerous gift of famotidine and Ferozsons Laboratorieslimited Nowshera Pakistan for providing FT-IR facilities

References

[1] Y Kawabata K Wada M Nakatani S Yamada and S OnoueldquoFormulation design for poorly water-soluble drugs based onbiopharmaceutics classification system basic approaches andpractical applicationsrdquo International Journal of Pharmaceuticsvol 420 no 1 pp 1ndash10 2011

[2] S Das W K Ng P Kanaujia S Kim and R B H TanldquoFormulation design preparation and physicochemical charac-terizations of solid lipid nanoparticles containing a hydrophobicdrug Effects of process variablesrdquo Colloids and Surfaces BBiointerfaces vol 88 no 1 pp 483ndash489 2011

[3] H Harde M Das and S Jain ldquoSolid lipid nanoparticles Anoral bioavailability enhancer vehiclerdquo Expert Opinion on DrugDelivery vol 8 no 11 pp 1407ndash1424 2011

[4] B Sarmento S Martins D Ferreira and E B Souto ldquoOralinsulin delivery by means of solid lipid nanoparticlesrdquo Interna-tional Journal of Nanomedicine vol 2 no 4 pp 743ndash749 2007

[5] R H Muller K Mader and S Gohla ldquoSolid lipid nanoparticles(SLN) for controlled drug deliverymdasha review of the state of theartrdquo European Journal of Pharmaceutics and Biopharmaceuticsvol 50 no 1 pp 161ndash177 2000

[6] W Mehnert and K Mader ldquoSolid lipid nanoparticles pro-duction characterization and applicationsrdquo Advanced DrugDelivery Reviews vol 47 no 2-3 pp 165ndash196 2001

[7] R ShahD Eldridge E Palombo and IHarding ldquoOptimisationand stability assessment of solid lipid nanoparticles usingparticle size and zeta potentialrdquo Journal of Physical Science vol25 no 1 pp 59ndash75 2014

[8] H A Ebrahimi Y Javadzadeh M Hamidi and M B JalalildquoRepaglinide-loaded solid lipid nanoparticles effect of usingdifferent surfactantsstabilizers on physicochemical propertiesof nanoparticlesrdquoDARU Journal of Pharmaceutical Sciences vol23 no 1 article 46 2015

[9] C Vitorino F A Carvalho A J Almeida J J Sousa andA A C C Pais ldquoThe size of solid lipid nanoparticles Aninterpretation from experimental designrdquo Colloids and SurfacesB Biointerfaces vol 84 no 1 pp 117ndash130 2011

[10] Y Kinoshita T Hashimoto A Kawamura et al ldquoEffects offamotidine mosapride and tandospirone for treatment of func-tional dyspepsiardquo Alimentary Pharmacology and TherapeuticsSupplement vol 21 no s2 pp 37ndash41 2005

[11] D P Patel R R Shah A P Patel and P K Tank ldquoDevelop-ment and validation of first order derivative uv-spectroscopic


method for estimation of ibuprofen and famotidine in syntheticmixturerdquo Pharma science Monitor vol 3 no 4 2012

[12] R M O Aman M M O Meshali and G M A AbdelghanildquoIon-exchange complex of famotidine sustained release andtaste masking approach of stable liquid dosage formrdquo DrugDiscoveries ampTherapeutics vol 8 no 6 pp 268ndash275 2014

[13] F M Mady A E Abou-Taleb K A Khaled et al ldquoEvaluationof carboxymethyl-120573-cyclodextrin with acid function Improve-ment of chemical stability oral bioavailability and bitter taste offamotidinerdquo International Journal of Pharmaceutics vol 397 no1-2 pp 1ndash8 2010

[14] FMMadyA E Abou-Taleb KAKhaled et al ldquoEnhancementof the aqueous solubility and masking the bitter taste offamotidine using drugSBE-120573-CyDPovidone K30 complexa-tion approachrdquo Journal of Pharmaceutical Sciences vol 99 no10 pp 4285ndash4294 2010

[15] D J Patel and J K Patel ldquoDesign and evaluation of famotidinemucoadhesive nanoparticles for aspirin induced ulcer treat-mentrdquo Brazilian Archives of Biology and Technology vol 56 no2 pp 223ndash236 2013

[16] A Avdeef CM Berger and C Brownell ldquopH-metric solubility2 correlation between the acid-base titration and the saturationshake-flask solubility-pH methodsrdquo Pharmaceutical Researchvol 17 no 1 pp 85ndash89 2000

[17] K C Yeh A N Chremos J H Lin et al ldquoSingle-dosepharmacokinetics and bioavailability of famotidine in manResults of multicenter collaborative studiesrdquo Biopharmaceuticsamp Drug Disposition vol 8 no 6 pp 549ndash560 1987

[18] T Takabatake H Ohta M Maekawa et al ldquoPharmacokineticsof famotidine a newH2-receptor antagonist in relation to renalfunctionrdquo European Journal of Clinical Pharmacology vol 28no 3 pp 327ndash331 1985

[19] S A Wissing O Kayser and R H Muller ldquoSolid lipidnanoparticles for parenteral drug deliveryrdquo Advanced DrugDelivery Reviews vol 56 no 9 pp 1257ndash1272 2004

[20] M Abbaspour B S Makhmalzadeh Z Arastoo A Jahangiriand R Shiralipour ldquoEffect of anionic polymers on drug loadingand release from clindamycin phosphate solid lipid nanoparti-clesrdquo Tropical Journal of Pharmaceutical Research vol 12 no 4pp 477ndash482 2013

[21] K-H Song S-J Chung and C-K Shim ldquoEnhanced intestinalabsorption of salmon calcitonin (sCT) from proliposomescontaining bile saltsrdquo Journal of Controlled Release vol 106 no3 pp 298ndash308 2005

[22] N Venkatesan K Uchino K Amagase Y Ito N Shibata andK Takada ldquoGastro-intestinal patch system for the delivery oferythropoietinrdquo Journal of Controlled Release vol 111 no 1-2pp 19ndash26 2006

[23] M Rehman A Madni A Ihsan et al ldquoSolid and liquidlipid-based binary solid lipid nanoparticles of diacerein Invitro evaluation of sustained release simultaneous loading ofgold nanoparticles and potential thermoresponsive behaviorrdquoInternational Journal of Nanomedicine vol 10 pp 2805ndash28142015

[24] B Ozturk S Argin M Ozilgen and D J McClementsldquoFormation and stabilization of nanoemulsion-based vitamin edelivery systems using natural surfactants Quillaja saponin andlecithinrdquo Journal of Food Engineering vol 142 pp 57ndash63 2014

[25] W Abdelwahed G Degobert S Stainmesse and H FessildquoFreeze-drying of nanoparticles formulation process and stor-age considerationsrdquo Advanced Drug Delivery Reviews vol 58no 15 pp 1688ndash1713 2006

[26] B Tita A Fulias G Bandur E Marian and D Tita ldquoCompati-bility study between ketoprofen and pharmaceutical excipientsused in solid dosage formsrdquo Journal of Pharmaceutical andBiomedical Analysis vol 56 no 2 pp 221ndash227 2011

[27] S Uprit R K Sahu A Roy and A Pare ldquoPreparation and char-acterization of minoxidil loaded nanostructured lipid carriergel for effective treatment of alopeciardquo Saudi PharmaceuticalJournal vol 21 pp 379ndash385 2013

[28] A Dubes H Parrot-Lopez W Abdelwahed et al ldquoScanningelectron microscopy and atomic force microscopy imaging ofsolid lipid nanoparticles derived from amphiphilic cyclodex-trinsrdquo European Journal of Pharmaceutics and Biopharmaceu-tics vol 55 no 3 pp 279ndash282 2003

[29] C Racault F Langlais and R Naslain ldquoSolid-state synthesisand characterization of the ternary phase Ti3SiC2rdquo Journal ofMaterials Science vol 29 no 13 pp 3384ndash3392 1994

[30] D Hou C Xie K Huang and C Zhu ldquoThe production andcharacteristics of solid lipid nanoparticles (SLNs)rdquoBiomaterialsvol 24 no 10 pp 1781ndash1785 2003

[31] A del Pozo-Rodrıguez M A Solinıs A R Gascon and JL Pedraz ldquoShort- and long-term stability study of lyophilizedsolid lipid nanoparticles for gene therapyrdquo European Journal ofPharmaceutics and Biopharmaceutics vol 71 no 2 pp 181ndash1892009

[32] U Bhardwaj and D J Burgess ldquoA novel USP apparatus 4 basedrelease testing method for dispersed systemsrdquo InternationalJournal of Pharmaceutics vol 388 no 1-2 pp 287ndash294 2010

[33] A C Moffat M D Osselton B Widdop and L Y GalichetldquoClarkersquos analysis of drugs and poisonsrdquo 2004

[34] Roohullah Z Iqbal F Nasir et al ldquoSustained release car-bamezapine matrix tablets prepared by solvent-evaporationtechnique using different polymersrdquo Middle East Journal ofScientific Research vol 15 no 10 pp 1368ndash1374 2013

[35] F Barboza D D Vecchia M P Tagliari M A S Silva andH K Stulzer ldquoDifferential scanning calorimetry as a screeningtechnique in compatibility studies of acyclovir extended releaseformulationsrdquo Pharmaceutical Chemistry Journal vol 43 no 6pp 363ndash368 2009

[36] P Costa and J M Sousa Lobo ldquoModeling and comparisonof dissolution profilesrdquo European Journal of PharmaceuticalSciences vol 13 no 2 pp 123ndash133 2001

[37] A A Sadiq and A Abdul Rassol ldquoFormulation and evaluationof silibinin loaded solid lipid nanoparticles for peroral usetargeting lower part of gastrointestinal tractrdquo Int J PharmPharmSci vol 6 no 1 pp 55ndash67 2014

[38] M Barzegar-Jalali ldquoKinetic analysis of drug release fromnanoparticlesrdquo Journal of Pharmacy Pharmaceutical Sciencesvol 11 no 1 pp 167ndash177 2008

[39] A Kovacevic S Savic G Vuleta R H Muller and C MKeck ldquoPolyhydroxy surfactants for the formulation of lipidnanoparticles (SLN and NLC) effects on size physical stabilityand particle matrix structurerdquo International Journal of Pharma-ceutics vol 406 no 1-2 pp 163ndash172 2011

[40] H Baharifar G Tavoosidana R Karimi et al ldquoOptimization ofself-assembled chitosanstreptokinase nanoparticles and evalu-ation of their cytotoxicity and thrombolytic activityrdquo Journal ofNanoscience andNanotechnology vol 15 no 12 pp 10127ndash101332015

[41] P P Kumar P Gayatri R Sunil S Jagamohan and Y MRao ldquoAtorvastatin loaded solidlipid nanoparticles formulationoptimization and in vitro characterizationrdquo IOSR Journal ofPharmacy vol 2 no 5 pp 23ndash32 2012


[42] J LiuW Hu H Chen Q Ni H Xu and X Yang ldquoIsotretinoin-loaded solid lipid nanoparticles with skin targeting for topicaldeliveryrdquo International Journal of Pharmaceutics vol 328 no 2pp 191ndash195 2007

[43] H S M Ali P York A M A Ali and N Blagden ldquoHydrocorti-sone nanosuspensions for ophthalmic delivery A comparativestudy betweenmicrofluidic nanoprecipitation and wet millingrdquoJournal of Controlled Release vol 149 no 2 pp 175ndash181 2011

[44] Y Liu J Pan and S-S Feng ldquoNanoparticles of lipid monolayershell and biodegradable polymer core for controlled release ofpaclitaxel Effects of surfactants on particles size characteristicsand in vitro performancerdquo International Journal of Pharmaceu-tics vol 395 no 1-2 pp 243ndash250 2010

[45] S Khan M D Matas J Zhang and J Anwar ldquoNanocrystalpreparation low-energy precipitation method revisitedrdquo Crys-tal Growth and Design vol 13 no 7 pp 2766ndash2777 2013

[46] E S Farboud S A Nasrollahi and Z Tabbakhi ldquoNovel formu-lation and evaluation of a Q10-loaded solid lipid nanoparticlecream in vitro and in vivo studiesrdquo International Journal ofNanomedicine vol 6 pp 611ndash617 2011

[47] J Y Fang C L Fang C H Liu and Y H Su ldquoLipidnanoparticles as vehicles for topical psoralen delivery solidlipid nanoparticles (SLN) versus nanostructured lipid carriers(NLC)rdquo European Journal of Pharmaceutics and Biopharmaceu-tics vol 70 no 2 pp 633ndash640 2008

[48] A Khawam and D R Flanagan ldquoBasics and applications ofsolid-state kinetics a pharmaceutical perspectiverdquo Journal ofPharmaceutical Sciences vol 95 no 3 pp 472ndash498 2006

[49] B C Hancock and G Zografi ldquoCharacteristics and significanceof the amorphous state in pharmaceutical systemsrdquo Journal ofPharmaceutical Sciences vol 86 no 1 pp 1ndash12 1997

[50] S C Yang L F Lu Y Cai J B Zhu B W Liang and CZ Yang ldquoBody distribution in mice of intravenously injectedcamptothecin solid lipid nanoparticles and targeting effect onbrainrdquo Journal of Controlled Release vol 59 no 3 pp 299ndash3071999

Submit your manuscripts athttpswwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



CeramicsJournal of


CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



MetallurgyJournal of


BioMed Research International

MaterialsJournal of



S

NS N

SOO

N（2

（2

（2

（2

Figure 1 Chemical structure of famotidine

and are critical parameters in the stability and fabrication ofSLNs [9]These characteristics mainly depend upon particlescomposition and different fabrication techniques

Famotidine is widely used as competitive H2receptor

antagonist (H2RA) and prokinetic drug [10] Molecular

formula of famotidine is C8H15N7O2S3and IUPAC name

is 3-[[2-(diaminomethylideneamino)-13-thiazol-4-yl]meth-ylsulfanyl]-N1015840 sulfamoylpropanimidamide (Figure 1) Its keypharmacodynamic effect is the inhibition of gastric acidsecretion [11] It decreases stomach acid production up to 90when given in oral dosage form (20mg or 40mg) and pro-motes duodenal ulcer curing [12] It is used in the treatmentof heart-burn ulcer and inflammation of esophagus and highdoses are used for the treatment of conditions like Zollinger-Ellison syndrome It is commercially available in differentdosage forms like capsules tablets and also chewable tabletsfor adults Powder was also prepared for oral suspension butafter reconstitution its stability was limited to thirty days onlyand also had extremely bitter taste [12] Hence researchersalso tried numerous techniques to mask its bitter taste [13]Hydrophobic nature of famotidine reduces its water solubilityand also exposure to gastric degradation contributes to itsvariable and poor oral bioavailability [14]

Famotidine belongs to Class-IV drugs of biopharmaceu-tical classification system (BCS-IV) Drugs of this class showpoor aqueous solubility and low permeability [15] Due towhich its oral formulations have not been successful dueto low water solubility issues (11mgsdotmlminus1) and unfavorablepharmacokinetic parameters including low oral bioavail-ability (43) and a short plasma half-life (259 hrs) [16ndash18] Before selecting famotidine as drug model for loadinginto SLNs the available limited literature for addressing theoral bioavailability issues has been studied Patel DhavalJ et al 2010 have reported FTD nanosuspension havingminimum particle size of only 566 nm and also lackingstability study Also there has not been reported any in vivopharmacokinetic study

This research work was carried out to fabricate FTDloaded SLNs to enhance its aqueous solubility which in turnboost its oral bioavailability SLNs were fabricated by solventemulsification evaporation technique which is most suitablefor of thermosensitive drugs as it avoids thermal stress[19] SLNs have adhesive properties that could increase theresidence time in the administered area and hence enhanceits oral bioavailability [20] The use of tween-80 as surfactantandPVP as cosurfactantmay also improve oral bioavailabilityas they contribute to enhancing permeability aswell as affinitybetween lipids and intestinal membrane [21 22]

Table 1 Formulations of unloaded SLNs


Tween-80(ml)

PVP(g)

Stirring time(min)

UFSe-1 100 05 Nil 5UFSe-2 100 1 Nil 5UFSe-3 100 15 Nil 5UFSe-4 100 2 Nil 5UFSe-5 100 19 01 5UFSe-6 100 18 02 5UFSe-7 100 17 03 5UFSe-8 100 16 04 5UFSe-9 100 15 05 5UFSe-10 100 16 04 10UFSe-11 100 16 04 15UFSe-12 100 16 04 20PVP polyvinyl pyrrolidone

2 Materials and Methods

21 Materials Famotidine was procured as generous giftfrom Polyfine Chempharma (Pvt) Ltd (Peshawar Pakistan)Stearic acid and tween-80 were got from Acros OrganicsThermo Fisher Scientific New Jersey USA Polyvinylpyrroli-done (PVP-K30) was got from Crescent Chemical CompanyIslandia New York USA Dialysis bags were obtained fromSpectrum labCanada Remainingmaterials were of analyticalgrade or equivalent

22 Methods

221 Preparation of Unloaded SLNs Unloaded SLNs werefabricated by solvent emulsification evaporation (SEE) tech-nique using different surfactant (tween-80) concentrationcosurfactant (PVP) concentration and stirring time (Table 1)[19] Specified amount of stearic acid was dissolved inchloroform which was then emulsified with aqueous phasehaving surfactant (Tween-80) and cosurfactant (PVP) undermagnetic stirring (1000 rpm) to form microemulsion Inthis microemulsion aqueous phase contains micron-sizedroplets of organic solvent containing stearic acid Organicsolvent is evaporated from this microemulsion via magneticstirring As the organic solvent evaporates the lipid startsprecipitating as SLNs in the aqueous phase is followedby centrifugation using ultra-centrifuge Cs 150 GXL (Gx-Series) for 10 minutes at 30000 rpm [23] 119885-average particlesize and PDI of these formulations were figured out byphoton correlation spectroscopy using zeta-sizer Nano (ZS-90 Malvern Instruments Malvern UK) [24]

222 Preparation of FTD-SLNs Best conditions of UFSe-11formulation that is stearic acid (10 g) tween-80 (16ml)and PVP (04 g) were further used for fabricating FTDloaded SLNs (FTD-SLNs) Different formulations of FTD-SLNs were prepared on the basis of lipid drug ratio (Table 2)Specified quantity of FTD and stearic acid was dissolved in


Chloroform













FTD(mg)

Tween-80(ml)

PVP(g)

Stirring time(min)






EE



(1)




23 Characterization






















AUC0rarr24= AUC

0rarr24+119862119905

119870119890

(3)


119890is apparent



was determined by

119865119903=

AUC-FFSe-40rarr24


(4)


3 Results







04080120160200

0010203040506070809

1

Zeta

size

Poly

disp

ersit

yin

dex

(PD

I)

Formulations


SIZEPDI

UFS

e-1

UFS

e-2

UFS

e-3

UFS

e-4

UFS

e-5

UFS

e-6

UFS

e-7

UFS

e-8

UFS

e-9

UFS

e-10

UFS

e-11

UFS

e-12


0

5

10

15

20

()

Size (nm)


10E + 0410E + 0310E + 0210E + 0110E + 0010E minus 01







0

50000

100000

150000

200000

250000

minus200 minus100 0 100 200

Tota

l cou

nts

Zeta potential (mv)



0051152253354

020406080

100120


Dru

g lo

adin

g ca

paci

ty (

)

Entr

apm

ent e

ffici

ency

()

Formulations


EE ()DLC ()


1639

1284

1147

984

(A)

(B)16

14

12

10

8

6

2000 1800 1600 1400 1200 1000 800 600 400

(1cm)

T




0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta


FamotidineFFSe-4


(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature



S No Time(hrs)


1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194



0

50

100

150



Size

(nm

)


001020304050607



Poly

disp

ersit

y in

dex

(PD

I)





0rarr24for mar-


0rarr24











119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



Chloroform













FTD(mg)

Tween-80(ml)

PVP(g)

Stirring time(min)






EE



(1)




23 Characterization






















AUC0rarr24= AUC

0rarr24+119862119905

119870119890

(3)


119890is apparent



was determined by

119865119903=

AUC-FFSe-40rarr24


(4)


3 Results







04080120160200

0010203040506070809

1

Zeta

size

Poly

disp

ersit

yin

dex

(PD

I)

Formulations


SIZEPDI

UFS

e-1

UFS

e-2

UFS

e-3

UFS

e-4

UFS

e-5

UFS

e-6

UFS

e-7

UFS

e-8

UFS

e-9

UFS

e-10

UFS

e-11

UFS

e-12


0

5

10

15

20

()

Size (nm)


10E + 0410E + 0310E + 0210E + 0110E + 0010E minus 01







0

50000

100000

150000

200000

250000

minus200 minus100 0 100 200

Tota

l cou

nts

Zeta potential (mv)



0051152253354

020406080

100120


Dru

g lo

adin

g ca

paci

ty (

)

Entr

apm

ent e

ffici

ency

()

Formulations


EE ()DLC ()


1639

1284

1147

984

(A)

(B)16

14

12

10

8

6

2000 1800 1600 1400 1200 1000 800 600 400

(1cm)

T




0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta


FamotidineFFSe-4


(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature



S No Time(hrs)


1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194



0

50

100

150



Size

(nm

)


001020304050607



Poly

disp

ersit

y in

dex

(PD

I)





0rarr24for mar-


0rarr24











119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



















AUC0rarr24= AUC

0rarr24+119862119905

119870119890

(3)


119890is apparent



was determined by

119865119903=

AUC-FFSe-40rarr24


(4)


3 Results







04080120160200

0010203040506070809

1

Zeta

size

Poly

disp

ersit

yin

dex

(PD

I)

Formulations


SIZEPDI

UFS

e-1

UFS

e-2

UFS

e-3

UFS

e-4

UFS

e-5

UFS

e-6

UFS

e-7

UFS

e-8

UFS

e-9

UFS

e-10

UFS

e-11

UFS

e-12


0

5

10

15

20

()

Size (nm)


10E + 0410E + 0310E + 0210E + 0110E + 0010E minus 01







0

50000

100000

150000

200000

250000

minus200 minus100 0 100 200

Tota

l cou

nts

Zeta potential (mv)



0051152253354

020406080

100120


Dru

g lo

adin

g ca

paci

ty (

)

Entr

apm

ent e

ffici

ency

()

Formulations


EE ()DLC ()


1639

1284

1147

984

(A)

(B)16

14

12

10

8

6

2000 1800 1600 1400 1200 1000 800 600 400

(1cm)

T




0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta


FamotidineFFSe-4


(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature



S No Time(hrs)


1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194



0

50

100

150



Size

(nm

)


001020304050607



Poly

disp

ersit

y in

dex

(PD

I)





0rarr24for mar-


0rarr24











119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



04080120160200

0010203040506070809

1

Zeta

size

Poly

disp

ersit

yin

dex

(PD

I)

Formulations


SIZEPDI

UFS

e-1

UFS

e-2

UFS

e-3

UFS

e-4

UFS

e-5

UFS

e-6

UFS

e-7

UFS

e-8

UFS

e-9

UFS

e-10

UFS

e-11

UFS

e-12


0

5

10

15

20

()

Size (nm)


10E + 0410E + 0310E + 0210E + 0110E + 0010E minus 01







0

50000

100000

150000

200000

250000

minus200 minus100 0 100 200

Tota

l cou

nts

Zeta potential (mv)



0051152253354

020406080

100120


Dru

g lo

adin

g ca

paci

ty (

)

Entr

apm

ent e

ffici

ency

()

Formulations


EE ()DLC ()


1639

1284

1147

984

(A)

(B)16

14

12

10

8

6

2000 1800 1600 1400 1200 1000 800 600 400

(1cm)

T




0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta


FamotidineFFSe-4


(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature



S No Time(hrs)


1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194



0

50

100

150



Size

(nm

)


001020304050607



Poly

disp

ersit

y in

dex

(PD

I)





0rarr24for mar-


0rarr24











119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



0100200300400500600700800900

10005

85 12

155 19

225 26

295 33

365 40

435 47

505 54

575 61

645 68

715 75

785

Cou

nts

2 Theta


FamotidineFFSe-4


(A)(B)(C)(D)

686∘C69∘C

160∘C1665∘C

1669∘C

0 50 100 150 200 250 300

Temperature



S No Time(hrs)


1 0 0 0 0 0 02 1 1198 1023 954 912 9023 2 2463 2057 2021 1686 15234 3 3742 3055 2965 2423 22545 4 4787 4134 3825 3212 28616 5 5883 5212 4715 3919 34547 6 6782 6211 5458 4598 40848 7 7653 6898 6189 5285 46979 8 8312 7634 7012 5912 528710 9 8897 8189 7626 6529 579811 10 9324 8812 8232 7084 637412 12 9921 9412 8831 7887 7194



0

50

100

150



Size

(nm

)


001020304050607



Poly

disp

ersit

y in

dex

(PD

I)





0rarr24for mar-


0rarr24











119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of










119865119903 525(119899 = 6 119909plusmn SD)

0

20

40

60

80

100

120

0 1 2 3 4 5 6 7 8 9 10 12

Perc

ent r

eleas

e

Time (hrs)

FFSe-1FFSe-2FFSe-3

FFSe-4FFSe-5




0

04

08

12

16

2

0 05 1 15 2 6 12 18 24Time (hrs)



Con

cent

ratio

n (

g)











4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of







4 Conclusion





Acknowledgments


References





























































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



















































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



















CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of









CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Documents

Fabrication, Characterization, and In Vivo Evaluation of