tailieunhanh - HPLC for Pharmaceutical Scientists 2007 (Part 17)

Developing fast high-performance liquid chromatography (HPLC) methods can improve work efficiency during research, development, or production of a drug substance or a drug product. HPLC is a key technique in all of these areas. Until recently, analysis times of greater than 30 minutes were common. Modern pharmaceutical R&D, with its high-throughput screening, demands high-throughput methods to deal with the large number of samples. To reduce production cycle time, fast HPLC methods are essential for on-line or at-line process control and for rapid release testing. Consider a GMP laboratory responsible for releasing a single batch of drug substance. . | 17 DEVELOPMENT OF FAST HPLC METHODS Anton D. Jerkovich and Richard V. Vivilecchia INTRODUCTION Developing fast high-performance liquid chromatography HPLC methods can improve work efficiency during research development or production of a drug substance or a drug product. HPLC is a key technique in all of these areas. Until recently analysis times of greater than 30 minutes were common. Modern pharmaceutical R D with its high-throughput screening demands high-throughput methods to deal with the large number of samples. To reduce production cycle time fast HPLC methods are essential for on-line or at-line process control and for rapid release testing. Consider a GMP laboratory responsible for releasing a single batch of drug substance. Assuming a run time of 30 minutes and a total of 12 injections a run time of 6 hours would be required to cover system suitability calibration and sample analysis. If the run time were 5 minutes only 1 hour would be required for the analysis. With the advent of commercial chromatographic porous media of less than 5 pm and more recently in the 1- to 2-pm range analyses times of less than 1-2 minutes have been demonstrated. Hundreds of samples which required days can now be analyzed in less than a day. This chapter will focus on how to optimize isocratic and gradient methods for speed without sacrificing resolution. In addition the implication on selection of column dimensions and media particle size on the speed of methods development will also be discussed. Reducing chromatographic media particle size allows the number of theoretical plates per second to be increased. However due to the resolution HPLC for Pharmaceutical Scientists Edited by Yuri Kazakevich and Rosario LoBrutto Copyright 2007 by John Wiley Sons Inc. 765 766 DEVELOPMENT OF FAST HPLC METHODS dependence on N1 2 doubling of N will only increase resolution by 21 2. As discussed below a reduction in particle size can lead to a pressure limitation due to the inverse .