Simultaneous determination of seven alkaloids from Rhizoma Corydalis Decumbentis in rabbit aqueous humor by LC-MS/MS: Application to ocular pharmacokinetic studies

This study aims to establish a fast and sensitive LC-MS/MS method for simultaneous determination of seven alkaloids from Rhizome Corydalis Decumbentis in rabbit aqueous humor. Aqueous humor samples were processed by protein precipitation and then separated on a Thermo Syncronis Cut column (50 mm x 2.1 mm, 5 mu m) with a mobile phase using acetonitrile-0.05% formic acid (28:72, v/v). Detection of the analytes and the internal standard (coptisine) were performed in positive electrospray ionization with selected reaction monitoring. The method showed good linearity (r > 0.9931) for all the seven alkaloids. This fully validated method was applied to the studies of aqueous humor pharmacokinetics of seven alkaloids from Rhizome Corydalis Decumbentis and the effects of bomeol on corneal penetration of these alkaloids into aqueous humor. This is the first work that presents a reliable LC-MS/MS method for simultaneous determination of seven alkaloids in rabbit aqueous humor and its application of ocular pharmacokinetics of seven alkaloids from Rhizome Corydalis Decumbentis.