ABSTRACT
Objective: To develop the quantitative analysis method combined with laser microdissection and LC-MS/MS technique for determinating sanguinarine, protopin, allocryptopine, chelerythrine, dihydrochelerythrine, and dihydrosanguinarine in the roots of Macleaya cordata, and performe the histochemical study on M. cordata roots. Methods: The technology of laser-microdissection was used to dissect the cork, cortex, phloem, xylem vascular bundles, and xylem rays from 2-year-old M. cordata roots at different growth stages, the technique of LC-MS/MS was applied to detecting the contents of targeted alkaloids in the microdissected tissues. Results: The six kinds of alkaloids possesed a wide linear ranges and a good linear relationship (r2 > 0.996 6); The RSD of intra- and inter-day precision was all less than 2.4%; The highest limits of detection and quantification were respectively 0.29 and 0.57 ng/mL; The repeatability RSD was below 13.2%. The recovery varied from 85.1% to 133.9%, and its RSD ranged from 9.4% to 20.7%. The total amounts of six kinds of alkaloids in the above five tissues were respectively 0.14, 0.10, 0.07, 0.16 and 0.11 μg/mm2 for seedling stage root; 0.38, 0.22, 0.15, 0.41 and 0.26 μg/mm2 for flowering stage root; 0.46, 0.29, 0.27, 0.55 and 0.22 μg/mm2 for fruit stage root, and 0.52, 0.29, 0.24, 0.41 and 0.23 μg/mm2 for latering fruit stage root. Conclusion: The integrated method is high-resolution, specific, sensitive, and reliable for the quantitative analysis of alkaloid in tissues; The six kinds of alkaloids are mainly located in corks and xylem vascular bundles from the roots of M. cordata.