This article describes the use of ultrahigh-pressure liquid chromatography (UHPLC) in pharmaceutical analysis of drug substances and drug products with UV absorption detection. The fundamentals and benefits of UHPLC in increasing analysis speed and resolution are reviewed. Its performance (precision, extra column dispersion, sensitivity, and column life) in pharmaceutical analysis was assessed. Several case studies on method development of an over-the-counter product, a complex formulation, and a drug substance are presented to illustrate the utility and benefits of UHPLC. Practical issues on system compatibility to existing methods, injection precision, system carryover, and sensitivity for low-UV absorption detection, as well as regulatory aspects on method adjustment and modification, are discussed. High performance liquid chromatography (HPLC) is the predominant analytical technique for pharmaceutical analysis. A fundamental weakness of HPLC has been its moderate separation efficiency (or resolution) and speed, limiting its utility for very complex mixtures (1-5). One straightforward approach to enhancing HPLC performance is the use of columns packed with very small particle diameters (dp). However, since the pressure drop of the column is inversely proportional to dp^, a very high system pressure will be required unless short columns are used (2, 4, 5). In the last four decades, HPLC performance has been constrained by a system pressure limit of 6000 psi in most systems — effectively limiting its separation performance to a column efficiency (N) of —20,000 plates or a peak capacity (P^. or «, number of peaks that can be resolved in the chromatogram) of ~200 (1,3,5). One potential approach to reduce the pressure drop of small-particle columns is to use high column temperatures. However, for pharmaceutical analysis, column temperature is typically limited to

Submit manuscripts at https://www.scholarscentral.org/submissions/industrial-electronics-applications.html or an e-mail attachment to the Editorial Office at manuscripts@scitechnol.com

Best Regards,
Editorial Manager
Journal of Pharmaceutical Sciences & Emerging Drugs
Email: editor.jpsed@peerjournal.org