High performance liquid chromatographic separation of thirteen drugs collected in Chinese Pharmacopoeia 2010(Ch.P2010) on cellulose ramification chiral stationary phase / 药物分析学报

The enantiomers separation of thirteen drugs collected in Ch.P2010 was performed on chiral stationary phase of cellulose ramification (chiralpak OD and chiralpak OJ) by high performance liquid chromatographic (HPLC) methods,which included ibuprofen (Cl),ketoprofen (C2),nitrendipine (C3),nimodipine (C4),felodipine (C5),omeprazole (C6),praziquantel (C7),propranolol hydrochloride (C8),atenolol (C9),sulpiride (C10),clenbuterol hydrochloride (C11),verapamil hydrochloride (C12),and chlorphenamine maleate (C13).The mobile phase consisted of isopropanol and n-hexane.The detection wavelength was set at 254 nm and the flow rate was 0.7 mL/min.The enantiomers separation of these thirteen racemates on chiralpak OD column and chiralpak OJ column was studied,while the effects of proportion of organic additives,alcohol displacer and temperature on the separation were studied.And the mechanism of some of racemates was discussed.The results indicated that thirteen chiral drugs could be separated on chiral stationary phase of cellulose ramification in normal phase chromatographic system.The chromatographic retention and resolution of enantiomers could be adjusted by factors including column temperature and the concentration of alcohol displacer and organic alkaline modifier in mobile phase.It was shown that the resolution was improved with reducing concentration of alcohol displacer.When concentration of organic alkaline modifier was 0.2％ (v/v),the resolution and the peak shape were fairly good.Most racemates mentioned above had better resolution at column temperature of 25 ℃.When racemates were separated,the temperature should be kept so as to obtain stable separation results.

Study on chiral separation of three drugs collected pharmacopoeia N-alkyl group by HPLC using chiral mobile phase additive and its mechanism / 中国药学杂志

OBJECTIVE: To performe chiral separation of three pharmaceutical racemates collected in Ch. P 2010 containing N-alkyl groups, including verapamil hydrochloride, chlorphenamine maleate, and chloroquine diphosphate by using SBE-β-CD as a mobile-phase additive in an HPLC system. METHODS: The analysis was carried out on an Alltima C18 column. The mobile phase consisted of acetonitrile and a phosphate solution added with SBE-β-CD and NaH2PO4, whose pH value was adjusted to 2.5 by phosphoric acid. The flow rate was set at 0.8 mL · min-1, and the column temperature was 25°C. The UV detection was carried out at 332, 264 and 278 nm, respectively. The effects of different factors on the separation effect were investigated, including CD types (β-CD, HP-β-CD), SBE-β-CD concentration, pH value, oven temperature, and buffer concentration. RESULTS: The established method was able to separate the three racemates and the mechanism had been discussed. CONCLUSION: Three racemates can be separated on C18 column using SBE-β-CD as a chiral mobile phase additive. This method might be applied to separate various types of biologically important enantiomers which have N-alkyl groups in the chemical structure.