Re-evaluation of anion-exchange HPLC for the analysis of acidic compounds.
A number of weak and strong anion-exchange HPLC phases have been evaluated for the analysis of acidic drugs and related compounds. Using eluents with high organic content, reasonable chromatography could be obtained and widely differing compounds easily separated in isocratic mode. Retention was related to solute pKa and concentration of ammonium acetate in the eluent. All the phases showed an unexplained loss in retention with repeated use, although with one material; nucleosil SAX, this was low (15%) and considered acceptable. This material was also shown to be relatively stable under typical bioanalytical conditions.
Law
B
B
Zeneca Pharmaceuticals, Lead Discovery Department, Macclesfield, Cheshire, UK. brian.law@astrazeneca.com
Hussain
M A
MA
D000085:Acetates; D000143:Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations / Q000032:analysis*; D012997:Solvents
D000085:Acetates; D000143:Acids; D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations; D012997:Solvents; C018824:ammonium acetate