Pharmaceutical Applications of Liquid Chromatography

March 9, 2009
Helen Castro

Managing Editor, Spectroscopy

E-Separation Solutions

Welcome back to Chicago and Pittcon 2009. It?s likely to be a lot colder here than it was for Pittcon 2008 in New Orleans, but there should be no shortage of interesting sessions to attend this week.

Welcome back to Chicago and Pittcon 2009. It’s likely to be a lot colder here than it was for Pittcon 2008 in New Orleans, but there should be no shortage of interesting sessions to attend this week.

The Sunday afternoon session entitled “Pharmaceutical Applications of Liquid Chromatography” is a good example. Dujuan Lu, Stephen Weber, and Chen Zhi opened the session with “Binding Measurements by a High-Throughput Phase-Distribution Method,” discussing a method that has been developed to measure drug-cyclodextrin binding constants and the pKa values of drugs.

Next, David S. Bell, Craig Aurand, Jennifer Claus, Jay Jones, and Dan Shollenberger presented “Retention Mechanisms in Chiral Chromatography: LC–MS Analysis Using Macrocyclic Glycopeptide and Cyclodextrin Chiral Stationary Phases,” which explored the impact of variables such as ion concentration, acid/base ratios, organic modifier type, and pH on enantiomeric selectivity for a wide range of pharmaceutically relevant compounds.

That presentation was followed by Adam Peter Schellinger’s “Creative Applications of Fast Resolution High Performance Liquid Chromatography (FR-HPLC) for Monitoring the Synthesis of Active Pharmaceutical Ingredients.” He shared some recent examples of how his team decreased the analysis time of methods for in-process monitoring (reaction completion, product concentration) and for purity/potency determination of isolated intermediates while maintaining acceptable resolution using conventional HPLC instrumentation, which has led to useful guidelines for choosing the “fastest” column with adequate efficiency for use with conventional instrumentation.

Just before breaking for recess, Peter C. Rahn and William Cash gave a presentation entitled “Preparative Purifications of Pharmaceutically Active Chiral Compounds in Axial Compressed Columns.” This presentation covered how packing a new family of rugged, mechanically stable cellulose and amylose-based chiral stationary phases using axial compression technology makes the purification of chiral compounds less daunting.

After a brief recess, attendees heard about “Analysis of Pharmaceuticals Using Ion-Exchange/Reversed-Phase Mixed-Mode Chromatography” from Xiaodong Liu and Christopher Pohl. They discussed development of three new mixed-mode columns (RP/anion-exchange, RP/cation-exchange, and RP/both anion- and cation-exchange) for analyzing pharmaceutical formulations, and were followed by Jun Lu, with “Development and Validation of a Novel Stability-Indicating Reversed-Phase High Performance Liquid Chromatography Method for Assay of Loratadine and Estimation of its Related Compounds.”

The next presentation was given by Kihwan Choi, Jungyeon Kim, Jihye Kim, and Doo Soo Chung. “In-Line Coupling of Single Drop Microextraction for the Analysis of Basic Drugs in Urine by Capillary Electrophoresis–Mass Spectrometry” was an informative look at how basic analytes in urine samples were successfully analyzed with SDME/CE, followed by mass spectrometry detection for identification of compounds in the urine sample.

The final presentation for this session was delivered by Peter C. Rahn. Entitled “Improved Preparative Yield with Higher pH Mobile Phases,” it focused on how the introduction of new silica-based media that are stable to either acidic or basic conditions provides chemists with more flexibility in choosing mobile phase conditions and improves throughput in the laboratory.

With so many interesting sessions to attend, this week at Pittcon is sure to be both busy and educational. I’m already looking forward to tomorrow!