Gyllenhaal Olle
Analytical Development, AstraZeneca R & D Mölndal, S-431 83 Mölndal, Sweden.
J Chromatogr A. 2004 Jul 9;1042(1-2):173-80. doi: 10.1016/j.chroma.2004.05.035.
This paper describes packed column supercritical fluid chromatography (SFC) for the analysis of a peroxysome proliferator-activating gamma-receptor agonist that is a carboxylic acid. Evaluation of conditions for the separation of this candidate drug and related compounds in bulk substance is described. A Chiralcel OD column was used for this purpose due to its high selective retention of related substances and relative inertness, though the enantioselectivity was negligible, with methanol as polar modifier. A high enantioselectivity was obtained on Chiralpak AD and it was possible to determine the enantiomeric purity within 10 min on a 5 cm short column. Both the achiral and the chiral systems were run without acid additive in the mobile phase and the level of detection of impurities by area was about 0.1%. For the analysis of samples dissolved in water, without any isolation step, 2-propanol was used as modifier. Due to the column surface activity, evidently generated by injected water, citric acid 1 mM was included as additive in the 2-propanol in order to maintain symmetric and undistorted peak shape. The detection limit for the assay was 21 microg mL(-1) (50 nmol mL(-1)) for 5 microL injected (R.S.D. 6.4%, n = 8). A 5 cm short Chiralcel OD column was used. Determination of enantiomeric purity of the drug in aqueous samples required increased sensitivity. The sample was acidified and extracted into a small volume of 1-pentanol, out of which 25 microl was analyzed by SFC. The minor enantiomer at the 3% (w/w) level added could be confirmed. Its ratio remained constant during the procedure as measured relative to a reference solution in organic media.
本文描述了填充柱超临界流体色谱法（SFC）用于分析一种作为羧酸的过氧化物酶体增殖物激活γ受体激动剂。文中介绍了对该候选药物及其原料药中相关化合物进行分离条件的评估。为此使用了Chiralcel OD柱，因其对相关物质具有高选择性保留且相对惰性，尽管对映体选择性可忽略不计，流动相中的极性改性剂为甲醇。在Chiralpak AD柱上获得了高对映体选择性，并且可以在一根5 cm的短柱上于10分钟内测定对映体纯度。非手性和手性系统在流动相中均未添加酸添加剂，杂质的面积检测限约为0.1%。对于未经任何分离步骤的水溶性样品分析，使用2-丙醇作为改性剂。由于进样水明显产生的柱表面活性，在2-丙醇中加入1 mM柠檬酸作为添加剂，以保持峰形对称且不失真。对于5 μL进样量，该测定的检测限为21 μg mL⁻¹（50 nmol mL⁻¹）（相对标准偏差6.4%，n = 8）。使用了一根5 cm的短Chiralcel OD柱。测定水性样品中药物的对映体纯度需要提高灵敏度。将样品酸化并萃取到少量1-戊醇中，取其中25 μL通过SFC进行分析。可以确认添加水平为3%（w/w）的次要对映体。相对于有机介质中的参比溶液测量，其比例在整个过程中保持恒定。
