Cherwell Releases Growth Promotion Testing Guide

By Gill Power

Providing key considerations and best practices when undertaking GPT for microbiological media QC

Bicester, UK, 26th January 2021: Cherwell Laboratories, specialist supplier of products for environmental monitoring and process validation, has drawn on its extensive pharmaceutical and related industry knowledge to publish an eBook titled, “Growth Promotion Testing: A Guide to Good Practices” which is available to download.

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The guide is intended for anyone involved in growth promotion testing of microbiological media, providing an overview of key considerations and best practice for this key quality control (QC) test. It particularly focuses on media used for pharmaceutical and sterile medical device industry applications; including environmental monitoring; process and operator validation; and product sterility testing.

Given the critical nature of microbiological quality tests employed to ensure the safety of pharmaceutical products for human use, it is essential to undertake QC tests confirming the media used is fit for purpose. Before a new batch of culture media can be released for any microbiological tests, particularly under pharmaceutical industry regulations, it must be properly tested for its ability to ensure consistent and reliable results. Growth promotion testing (GPT) is central to this.

The guide helps readers to ensure their GPT provides assurance of the final results of pharmacopoeial microbiology testing programmes by showing that the media used will perform as expected against accepted criteria. The eBook starts with the importance of good quality microbiological media; what GPT is, why it is essential and key pharmacopoeial requirements. It then details how GPT is performed, including best practices, frequently asked questions and tips for reliable results. The guide also highlights areas for consideration, such as: the need for a detailed QC certificate; using 3rd party labs for testing and how choice of media supplier impacts GPT.

Cherwell’s well established in-house Quality Team undertakes thousands of prepared media quality tests per month to ensure customers can be 100% confident in the quality of its Redipor® media. This enables them to share in-depth knowledge in the new eBook.

Steven Brimble, Cherwell Laboratories’ Quality Manager and Microbiologist comments: “I hope this guide helps advise users on best practices to assist them with fine tuning their GPT procedures for their own site and testing needs. That said, we are also only too happy to personally help with any specific questions that our customers may have when setting up their GPT programmes.”

With over thirty-five years’ experience in manufacturing Redipor® prepared media, Cherwell has in-depth insight and expertise that ensures it continually delivers prepared media of the highest calibre to its clients. Cherwell also maintains the personal touch that accompanies an ability to accommodate customers’ unique needs with bespoke solutions.



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