High pH and Elevated Temperatures for Fast Separation of Strongly Basic Drug Compounds
Two important but frequently underutilized tools in methods development are mobile phase pH and elevated temperatures.
Two important but frequently underutilized tools in methods development are mobile phase pH and elevated temperatures. Hamilton's PRP-C18 column is well-suited for high pH and high temperature applications because the polymer-based stationary phase is chemically inert and has excellent thermal stability above 100 °C.
In modern drug discovery, where analytical HPLC can be a bottleneck, production is streamlined through the use of shorter columns with smaller particles, operated at higher flow rates. The flexibility to employ a high pH mobile phase and elevated temperatures represents further valuable tactics in methods development. These tools, often underutilized or not practical with silica-based columns, enable rapid separation of closely-related basic solutes in their charge-neutral forms that would otherwise co-elute under non-alkaline, ambient temperature conditions.
Figure 1: Fast separation of structurally-diverse, basic solutes at 80 °C.
In this study, nine structurally-diverse, strongly basic drug compounds are resolved in less than 2 min using a high pH mobile phase and a fast acetonitrile gradient at 80 °C.
Analytes
1. Ephedrine
2. Norephedrine
3. Nicotine
4. Metoprolol
5. Quinine
6. Doxylamine
7. Diphenhydramine
8. Nortriptyline
9. Amitriptyline
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SEC-MALS of Antibody Therapeutics—A Robust Method for In-Depth Sample Characterization
June 1st 2022Monoclonal antibodies (mAbs) are effective therapeutics for cancers, auto-immune diseases, viral infections, and other diseases. Recent developments in antibody therapeutics aim to add more specific binding regions (bi- and multi-specificity) to increase their effectiveness and/or to downsize the molecule to the specific binding regions (for example, scFv or Fab fragment) to achieve better penetration of the tissue. As the molecule gets more complex, the possible high and low molecular weight (H/LMW) impurities become more complex, too. In order to accurately analyze the various species, more advanced detection than ultraviolet (UV) is required to characterize a mAb sample.
