Introduction

Although this time it’s not about pharmaceutical method validation¹, I’d like to take up an interesting question about the upper limit of linearity. We’ve got the following topic: For the performance of real-time polymerase chain reactions (RT-PCR) to detect SARS-CoV-2, the comparability of 2 thermal cyclers should be determined. For this purpose, the Ct values of the two thermal cyclers (let's call them A and B) were plotted against each other at different sample concentrations. 

As usual, I was once again accompanied on my last vacation by a technical book, which I’d now like to present. In this case, it is "Endotoxins and Pyrogens - Detection Methods, Product Testing, Inactivation", which was published by Michael Rieth at Wiley-VCH GmbH, Weinheim in 2021 as first edition (ISBN: 978-3-527-34695-0).

In today's blog article, we’d like to take a look at sterility testing and its verification. As this is a compendial method, we should talk about verification instead of validation in this context, even though unfortunately we often still read about validation of this method. To stick with the wording, in the pharmacopoeias this is referred to as method suitability test (MST), which in my opinion fits very well 😉 

Internal quality control (QC) – what’s that? You routinely perform laboratory analyses, but do you know whether your method also generates permanently reliable results? Yes of course, the method was validated once a long time ago, but since then...? Can you make a statement about the stability of the method? If such questions don't sound entirely unfamiliar, we’d like to introduce a tool today that precisely addresses this issue.