Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 17) doc

... size for use with elevated pressures has therefore been a necessary and critical advancement for UHPLC [32, 33].The superior loading capacity of these materials makes them practical for most pharmaceutical analyses. ... instrumentation are steps toward making UHPLC a viable tool for pharmaceutical analysis. Two pressure regimes have been described: very-high pressure LC (VHPLC),...

Ngày tải lên: 22/01/2014, 00:20

... that was optimized by Drylab, a forced degrada- tion sample was run that was stressed at 50°C for 1 week in pH 1 diluent. It was noted that a major impurity was formed (Figure 8-49) and was determined to ... isocratic conditions for deter- mining the most suitable pH for the method. The retention behavior of active as a function of pH (isocratic) was determined. The best mobile-phase pH...

Ngày tải lên: 15/12/2013, 12:15

... crystals that will damage the seal over time. Therefore it is recommended to wash the HPLC system with acetonitrile/water (20:80) for at least 30min before the system is shut down to remove any potential ... of analysis is critical to the success for fast and effective method development. The general approach for the method development for the separation of pharmaceutical compound...

Ngày tải lên: 24/12/2013, 18:15

... are three basic types of molecular forces: ionic forces, polar forces, and dispersive forces. Each specific technique capitalizes on each of these specific forces: 1. Polar forces are the dominant type ... employed in normal-phase HPLC (see Chapter 5). 2. Dispersive forces are employed in reversed-phase HPLC (see Chapter 4). 3. Ionic forces are employed in ion-exchange HPLC (see Chapter...

Ngày tải lên: 24/12/2013, 18:15

... in HPLC are porous particles with average diameters between 3 and 10µm. For most pharmaceutical applications, 3-µm particle sizes are recommended. Porosity provides the surface area necessary for ... (version 9.3). b Ligand length calculated using ACD software for the distance between anchoring oxygen and foremost atom in all-trans conformation of corresponding ligand. 3.6.2.1 Types...

Ngày tải lên: 24/12/2013, 18:15

... starting conditions for method development by using information of similar separations 503 HPLC for Pharmaceutical Scientists, Edited by Yuri Kazakevich and Rosario LoBrutto Copyright © 2007 by John ... and pharmaceutical information provides a basis for a significant increase of devel- opment efficiency. If analytical chemists from the various areas of drug development (drug met...

Ngày tải lên: 22/01/2014, 00:20

... specific class for the drug candidate is critical for future development of dosage forms. Different platforms are used for solubility measurements: UV; HPLC with UV detection; or HPLC with MS detection. ... suggests the necessity to formulate it in the form of salt. The reader is referred to ref- erence 46 for more information about the properties, selection, and use of salt forms...

Ngày tải lên: 22/01/2014, 00:20

... or microorganisms to screen their spectrum of 605 HPLC for Pharmaceutical Scientists, Edited by Yuri Kazakevich and Rosario LoBrutto Copyright © 2007 by John Wiley & Sons, Inc. baseline setup, ... treated as a whole (for more details see www.fda.gov; General Principles of Software Validation; Final Guidance for Industry and FDA Staff, January 11, 2002). The PQ is usually perf...

Ngày tải lên: 22/01/2014, 00:20

... is highly unlikely that the synthetic process 641 HPLC for Pharmaceutical Scientists, Edited by Yuri Kazakevich and Rosario LoBrutto Copyright © 2007 by John Wiley & Sons, Inc. of blanks injected ... than ELSD [24]. HPLC DETECTORS 655 Electrochemical detection can be utilized for compounds that are ionic or readily oxidizable or reducible .Thus, this form of detection can be...

Ngày tải lên: 22/01/2014, 00:20

... the two sets of crystals, the molecules are 987 HPLC for Pharmaceutical Scientists, Edited by Yuri Kazakevich and Rosario LoBrutto Copyright © 2007 by John Wiley & Sons, Inc. mobile phases ... conformation with the N-TFA-α-amino acid isopropyl ester. (Reprinted from reference 36, with permission.) The introduction of the diamide derivatives for enantiomeric separation was a ste...

Ngày tải lên: 26/01/2014, 19:20