TLC–MS identification of alkaloids in Leonuri Herba and Leonuri Fructus aided by a newly developed universal derivatisation reagent optimised by the response surface method

Introduction Dragendorff's reagent has low sensitivity and non‐specificity for some alkaloids. A new alkaloid derivatisation reagent has been developed and optimised by using a Box–Behnken design method. This new reagent is applicable for structurally diverse natural alkaloids, and is proposed as a universal alkaloid staining reagent. Objective To establish an efficient and sensitive thin‐layer chromatography (TLC) identification method for...