High-performance liquid chromatography with on-line coupled UV, mass spectrometric and biochemical detection for identification of acetylcholinesterase inhibitors from natural products

A high-performance liquid chromatography (HPLC) method with on-line coupled ultraviolet (UV), mass spectrometry (MS) and biochemical detection for ace tylcholinesterase (AChE) inhibitory activity has been developed. By combini ng the separation power of HPLC, the high selectivity of biochemical detect ion, and the ability to provide molecular mass and structural information o f MS, AChE inhibitors can be rapidly identified. The biochemical detection was based on a colorimetric method using Ellman's reagent. The detection li mit of galanthamine, an AChE inhibitor, in the HPLC-biochemical detection i s 0.3 nmol. The three detector lines used, i.e., UV, MS and Vis for the bio chemical detection were recorded simultaneously and the delay times of the peaks obtained were found to be consistent. This on-line post-column detect ion technique can be used for the identification of AChE inhibitors in plan t extracts and other complex mixtures such as combinatorial libraries. (C) 2000 Elsevier Science B.V. All rights reserved.