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ICH Testing of Pharmaceuticals – Part 2 - Sample Preparation

Atlas Suntest CPS+ with ICH Sample powder holder

ICH Q1B Requirements for Photostability Testing

In an earlier post, we discussed the basic ICH Q1B requirements. We saw that the SUNTEST provides great speed of testing, and we also discussed the often-heard statement of UV “over-exposure”. In this post, we will discuss the matter of sample preparation by looking at three simple but important examples.

1. Sample Thickness of Crystalline Powders

When it comes to sample thickness of crystalline powders, preparations up to 3 mm will work. To our knowledge, 3+ mm preparations are too thick as light won’t be able to reach the lowest layer of powder in the sample holder. 1-2 mm preparations using ICH powder sample holders with quartz covers are ideal.

2. Dark Control Samples

Q1B recommends the use of “dark control” samples to gauge thermal degradation. The “dark control” samples can also be easily prepared by using aluminum foil on one side of your ICH sample holder to shield half of the sample from the light source.

Atlas Pharma Dark Control

3. Tablets and Pills in Bottles

If you are unsure about how to expose solid oral dosage forms (pills) in their immediate packaging, follow the guidelines provided by S. R. Thatcher et al in Pharmaceutical Photostability: A Technical Guide and Practical Interpretation of the ICH Guideline and Its Application to Pharmaceutical Stability (Pharmaceutical Technology North America, pg. 50-62, April 2001). Their figure speaks for itself:

Atlas Pharma Tablet Testing

More Information

Watch our recorded online seminar which summarizes all you need to know about Pharmaceutical Photostability Testing.

Download free Application Guides explaining how to use SUNTEST instruments for ICH testing.