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Professional Analytical and
Consulting Services, Inc.

Photostability of Pollutants, Drugs and Other Substances

PACS Course Number 168

9 AM to 5 PM

This is a practical course covering the basic principles of photostability and photostability testing of drugs and other substances. It is designed for those new to the field as well as those with some experience. Fundamental concepts, practical applications, and regulatory aspects will be covered. The course director, Dr. John M. Allen, has an extensive background in photochemistry and photostability testing. He will help participants solve practical problems.

Some major topics you will learn about in this one day course are:
1. Identification of substances that are likely to absorb light and undergo photoreactions resulting in poor photostability.
2. Practical approaches for perfoming drug photostability testing of drug substances in accordance with ICH guidelines
3. Evaluation, comparison, and selection of illumination sources used for photostability testing.
4. Practical approaches for actinometric (light dose) measurements during photostability testing
5. Specific approaches for dealing with photostability testing of solid drug samples (e.g,, tablets), powders, suspensions, liquid solutions, and other drug formulations.
6. Strategies for protection of drug samples and enhancement of photostability.
7. Participants are encouraged to bring with them actual photostability problems of general interest for discussion and development of strategies for solving these problems

PACS courses related to activated carbon are titled:

Course Registration is available. You may also register through an associated conference registration. Send it with a payment of $2250 to secure your course attendance. Hotel information and a map will be sent to confirm your registration. Please list your special interest(s) on the registration form. Enrollment is limited to assure your maximum course benefits. On-site PACS courses are available (most PACS courses can be provided at your time and place). Telephone PACS at 1.724.457.6576 if you need further information. PACS also provides laboratory testing and consulting services.

Photostability of Pollutants, Drugs and Other Substances

Course Instructor: Dr. John Allen under the auspices of PACS

Course Outline

  1. Introduction
    Historical perspectives
    Overview of drug photostability and photostability testing
  2. Practical and Theoretical Principles
    Absorption of electromagnetic radiation (EMR) by drug molecules
    Direct sunlight, window-filtered sunlight, and room light spectral energy distributions
    Effects of molecular structure on photostability: Functional groups that lead to poor photostability
    Photoreactions: Photolysis, photorearrangement, and energy transfer
    Effects of reactions involving photochemically generated transient intermediates on drug photostability and the importance of oxygen
  3. Compliance with ICH Guidelines for Photostability Testing of Drug Substances
    Light source options 1 and 2: Which option is best?
    Assessment and selection of commercially available photostability testing chambers
    Forced degradation and confirmatory testing
    Sample presentation: solid tablets, powders, suspensions, and liquid solutions
    Some issues associated with capsules: the importance of humidity control during photostability testing
    Selection of sample containers for photostability testing
    The importance of proper sample placement in photostability chambers
    Problems resulting from poor temperature control
    Analytical procedures for assessing photostability
    Use of radiometers
    Avoiding serious difficulties with chemical actinometry when using quinine
  4. Strategies for Improvement of Drug Photostability
    Titanium dioxide coating of tablets
    Proper choice of formulation excipients and drug photostability
    The use of photostabilizing excipients in formulations

This course introduces participants to the basic principles underlying drug photostability and to the practical aspects of drug photostability testing in accordance with ICH guidelines. Participants are encouraged to bring with them specific problems for evaluation and discussion.


View the PACS Short Course Calendar–>

Course participants are encouraged to e-mail questions:

George Nowicki
Lab Manager

Rich Capp
Office Administrator

Send samples and postal inquiries to:
PACS, Inc.
409 Meade Drive
Coraopolis, PA 15108

Other PACS contact information:
Phone: 1-724-457-6576 or 1-800-367-2587
PACS website:

Please list your special interest during registration. We will try to accommodate your interest.

Training is an Investment in employee employer Future!