Wednesday, 26 February 2014

MTS Recommends... Complying with Revised USP Chapters on Weighing

An overview of the USP's revised Chapters <41> and <1251>, which became official in December 2013, and have new requirements for weighing, including balance calibration and testing.

Friday, 7 February 2014

MTS Recommends... Drug-Excipient Interactions

Drug-Excipient Interactions

by Patrick Crowley and Dr Luigi G Martin, in Pharmaceutical Technology Europe, March 2001

I think that this article from back in 2001 will be a useful resource if you are performing forced degradation studies on drug products. It provides an excellent overview of potential drug-excipient interactions to consider.

Thursday, 6 February 2014

Help on: For how long should I equilibrate my HPLC column?

Do you have any problems relating to analytical chemistry for pharmaceuticals or training? Send your questions to the MTS helpdesk using our contact form.

"While operating an HPLC system my manufacturer told me to equilibrate my system for approx. 10 minutes. Though I came to know from available literature from various sources that equilibration time depends on column dimensions (which is coming out to be quite large). So what is the purpose of equilibration and how do we determine the time of equilibration? And also do I need to equilibrate every time I run my system?"

"Equilibration of an HPLC system is necessary to achieve reproducible chromatography and therefore quantitative results. It would seem that equilibration results in a stable and even distribution of the mobile phase within the stationary phase in the column and thus it is required every time a system is set up for analysis. It has been found that for best results, when an HPLC system is first set up, a minimum of 20 column volumes is required. We measure it in column volumes because the time taken will vary depending on the dimensions of the column (as you have discovered). There is a formula that you can use to determine how long a time will be required for 20 column volumes and I refer you to a blog that I have written on this subject: Equilibration of HPLC columns

I also provide a calculator that will work it out for you on my website which you may find useful: HPLC Calculator

Typical symptoms of incomplete equilibration are drifting baselines and retention times. You will also need to equilibrate your system between each injection if you use a gradient method, 10 column volumes is usually recommended."

If you would like more advice on equilibration and other HPLC-related issues, then why not come along to our HPLC courses on the 10th to 13th June 2014 in Dublin? You can choose from: 
  • How to Run HPLC Methods (10th June)
  • How to Troubleshoot HPLC (11th June)
  • How to Develop HPLC Methods - Part 1 (12th June)
  • How to Develop HPLC Methods - Part 2 (13th June)
Visit the MTS Course List for more information including course descriptions and course fees.


Tuesday, 4 February 2014

Free Aide Mémoire for Analytical Method Transfer is Updated!

The aide mémoire provided by MTS in the course, Transfer of Analytical Methods for Pharmaceutical Analysis, which assists in the review of analytical methods prior to transfer has been updated to include more considerations for transfer of HPLC methods.

The aide mémoire is a document in progress, if you have any ideas about what you think should be included then please send your suggestions to me using our Contact Us page.

Click on the image to the right, or click here, to access the download page for the free method transfer tool.