Comparative studies of transfer methods

Mark Oldcorne

To determine:

◦ the effect of different storage conditions on the

surface bioburden of items used during aseptic

preparation

◦ whether the material of the item affects surface

bioburden

◦ efficiency of SteriVal® method compared to

traditional contact plating

Manufacturers packaging was removed from two

item types:

• 0.9% sodium chloride 2ml glass ampoule with

coated paper label from Phoenix Pharma

• Lidocaine 2ml plastic ampoule with coated paper

label from Braun

SteriVal® (Helapet) “total immersion” method was

used to determine the surface bioburden on items.

The surface bioburden of each (n=10) was

determined immediately (t=0) and then after

exposure to three different environmental

conditions for 5 days

• Grade C cleanroom

• Grade D storage area

• Unclassified storage area

Graph of number of cfu after 5 days storage under different environmental conditions

0

5

10

15

20

25

30

35

From

man

ufactu

rers

box

Gra

de C cl

eanr

oom

Gra

de D st

orag

e ar

ea

Unclas

sified

sto

rage

are

a

Storage condition

Nu

mb

er o

f cf

u

Glass

Plastic

The surface bioburden of 50ml vials from a

single manufacturer was determined

2 methods utilised

◦ the SteriVal® total immersion method (n=10)

◦ contact plating with Tryptone Soya Agar (n=10)

Comparison of transfer validation results obtained using SteriVal method compared to contact plating

0

5

10

15

20

25

30

Study 1 Study 2

Me

an

cfu

Contact plating

SteriVal method

Initial surface bioburden affected by:

◦ Storage conditions

◦ Container material type

◦ Container manufacturer

SteriVal® method recovered

approximately double the number of cfu

compared to contact plating