Pharmaceutical Technology Europe - May 2012 - (Page 20)

ASK THE EXPERT Preventing Contamination with Preservatives If a product does not have its own antimicrobial properties, then a preservative must be used to ensure microbiological safety. Greg Snowdon from RSSL offers his advice on using preservatives. What are the main considerations regarding the use of antimicrobial preservatives? Microbiological safety should be considered throughout the product’s lifetime. A product that is susceptible to microbiological growth is deficient in several ways; for example, it may pose a risk if it supports the growth of pathogenic microorganisms. If the preparation itself does not possess sufficient anti-microbial properties, then preservatives must be added. Preservatives can extend a product’s shelf life and are essential to prevent the growth of microbes and stop product degradation. Is simply adding a recognised preservative sufficient to control contamination? Even if a preservative is known to be efficacious, it is still important to consider its potential interactions with the preparation. The API and the formulation into which the preservative is incorporated can decrease, or possibly increase, the preservative’s efficacy. For example, the preservative may react with the formulation in such a way that it reduces the concentration over time or renders it unavailable to interact with the microorganisms. There is also a consideration around the expected activity of the preservative against different types of microorganism. Some preservatives may not be as efficacious against fungi as they may be against bacteria, in which case a combination may be necessary. volatile preservative is used. If the preservative leaches into the packaging it can reduce the preservative levels below active concentrations. This factor is especially important to consider when moving a product to a new container material, such as from glass to PET. And what about storage conditions? Although it is true that a large number of pathogenic organisms will not proliferate at low temperatures, there are still plenty that aren’t as inhibited by refrigeration as you may think. If these start metabolising, then you can end up with some interesting by-products. There’s also the human factor to consider. Just because it says ‘keep in the fridge’ doesn’t guarantee Greg Snow don that someone won’t leave it out! Some bacteria have impressively fast growth cycles. E.coli, for example, can double every 20 minutes. How can packaging material affect a preservative? Packaging can affect a preservative, particularly if a Greg Snowdon is a microbiology scientist at RSSL. 2 PARTICLE ANALYSIS 17 GMP INSPECTIONS 10 NEWS 18 COLUMNS 12 BLOGS 10 PRESERVATIVES 16 CAPSULE FILLING 21 TOP TECH

Table of Contents for the Digital Edition of Pharmaceutical Technology Europe - May 2012

Pharmaceutical Technology Europe - May 2012
Contents
Experts discuss the importance of particle characteristics
News Bites
Blogs Abridged
Interview: Atomic Force Microscopy
Pan Coating and Scale-Up: a Guide Based on First Principles
Preparing Powders and Capsules
Top GMP Deficiencies
Column Crunch: French taxes; learning from Apple; ingredients; and GMP
Preventing Contamination with Preservatives
Top Tech

Pharmaceutical Technology Europe - May 2012