Organic Nanoparticles

Adapting EmergingTechniques from the

Electronics Industry forthe Generation of Shape-

Specific,Functionalized Carriers for

Applications inNanomedicine

Introduction

• In nanotechnology, a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties.

• Particles are further classified according to diameter.

• Coarse particles cover a range between 10,000 and 2,500 nanometers.

• Fine particles are sized between 2,500 and 100 nanometers.

• Ultrafine particles, or nanoparticles are sized between 1 and 100 nanometers.

Nanoparticles

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• However, during the 1990s before the National

Nanotechnology Initiative was launched in the USA, the

new name, "nanoparticle" had become fashionable.

• Nanoparticles may or may not exhibit size-related properties

that differ significantly from those observed in fine particles

or bulk materials.

• Nanoclusters have at least one dimension between 1 and 10

nanometers and a narrow size distribution.

• Nanometer-sized single crystals, or single-domain ultrafine

particles, are often referred to as nanocrystals.

Organic Nanostructure

• A nanostructure is an object of intermediate size between microscopic and molecular structures.

• Often common chromophores, vitamins, minerals, or drugs are encapsulated in silica or a larger "plastic" particle.

• Which are organic materials, liposomes, polymer nanocapsules.

• The use of liposomes in medical applications has received a great deal of attention during recent years.

Nanomedicine

• Nanomedicine is the application of nanotechnology (the engineering of tiny machines) to the prevention and treatment of disease in the human body. This evolving discipline has the potential to dramatically change medical science.

• Near-future nanomedicine applications include activity monitors, chemotherapy, pacemakers, biochip s, OTC tests, insulin pumps, needleless injectors, hearing aids, medical flow sensors and blood pressure, glucose monitoring and drug delivery systems.

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• The National Institutes of Health (NIH) have recently coined the term ‘‘Nanomedicine’’ to mean the application of nanotechnology for the treatment, diagnosis, monitoring, and control of biological systems

• At the forefront of research in this area is the development of methods to target and deliver pharmaceutically-relevant cargo and diagnostic and imaging agents.

• One of the current trends in nanomedicine materials development is toward tunable monodisperse nanostructures.

• Examples include colloidal gold, iron oxide crystals , quantum dots (CdSe/ZnS).

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• Nanomedicine has both the opportunity and the ability to

improve the effectiveness of drug delivery by targeting

pharmaceutically-relevant cargo to specific sites, by managing

the drug’s pharmacokinetics and pharmacodynamics, and

improving on its nonspecific toxicity and immunogenicity.

• Several areas of research are currently exploring the use of

NPs for drug delivery applications; these include liposomes,

micelles, and a variety of other polymeric NPs that are

composed of organic polymers with specific physical or

chemical properties that make them relevant delivery vehicles.

Micelles and liposomes in Nanomedicine

• Micelles – and liposomes in particular – are the subject of major interest for drug delivery applications.

• The surface can be modified such that the liposome is targeted to a specific receptor, leading in turn to reduced toxic side effects of the drug.

• Conventional liposomes have been used to carry and transport both antimicrobials and chemotherapeutics, as well as DNA and proteins.

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• Unfortunately, there are disadvantages to conventional liposomal carriers, the most prominent being rapid clearance from the blood and chemical and physical instability.

• Thus, clear advances have been made recently in the development of stabilized liposomes.

• For example, a polyethylene glycol (PEG) coating can be used to create long-circulating liposomal carriers.

Protein or Polymer conjucates

• In Nanomedicine, proteins are called as a polymer conjucates.

• Polymer–drug (or protein) conjugates are hybrid structures that tend to be water-soluble. (due to control of the chemical composition of the polymer)

• Use of polymers in biomedical materials applications — e.g., as prostheses, medical devices, contact lenses, dental materials and pharmaceutical excipients.

• synthetic polymer NPs have been developed as a more effective drug delivery method, to use of transport.

Nano Imaging

Nano imaging is the technique and process used to create images of the human body for clinical purposes or medical science.

Although imaging of removed organs and tissues can be performed for medical reasons, such procedures are not usually referred to as medical imaging, but rather are a part of pathology.

• Huang and co-workers have described the use of gold nanorods of a specific aspect ratio that absorb and scatter strongly in the near infrared region.

• These nanorods are conjugated to anti-epidermal monoclonal antibodies and can be used simultaneously for molecular imaging and photothermal cancer therapy.

• Iron oxide NPs cause spin-spin time relaxation changes innearby water molecules, and this property can be exploited to detect cancers or other diseases

Example - I

Ecample - II

• Likewise, Akerman have described the use of quantum dots (CdSe/ZnS) for targeted in vivo diagnostic imaging.

• Here, quantum dots are defined as inorganic nanocrystals less than 10 nm in size and with tunable fluorescent properties.

• Recently, Whitesides described using the technology of microfluidics to prepare monodisperse micron-sized particles that can be functionalized with magnetic NPs or dyes for use in imaging.

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• In addition to nanoimaging applications, nanomedicine can provide an array of opportunities for targeted drug delivery and controlled release applications.

• One of the nano imaging application for drug delivey is nanorobots.

• The most advanced nanomedicine involves the use of nanorobot is as miniature surgeons.

• Such machines might repair damaged cells, or get inside cells and replace or assist damaged intracellular structures.

• At the extreme, nanomachines might replicate themselves, or correct genetic deficiencies by altering or replacing DNA (deoxyribonucleic acid) molecules.

Nanorobot

Some types of Nanorobots

Nuclear Powered Nanorobots Nanorobots for drug delivery

Medical nanorobots drilling in a human body

Nanorobots on brain cells

Nanorobot for Brain