Plants and their secondary metabolites are the rich source of drugs against several diseases. Therefore, our aim of study was to characterize, standardize and to develop a fast and sensitive matrix free Material Enhance Laser Desorption Ionization Mass Spectrometry (mf-MELDI-MS) and High Performance Liquid Chromatography-Diode Array Detection-Electrospray Ionization Mass Spectrometry (HPLC-DAD-ESI-MS) method for the qualitative and quantitative determination of salicylic acid (SA), 3,4-dihydroxybenzoic acid (3,4-DHBA), gallic acid (GA) and gallic acid methyl ester (GAME) from crude plant...