ABSTRACT
Mass spectrometry (MS) analysis is an integral part of proteomics and facilitates several applications for the quantitative and qualitative analysis of peptides. Non-directed analysis functions are vital for the foregoing analysis; non-targeted analysis is generally used during the discovery phase, to obtain more information. Non-directed analysis is an MS/MS screening method to identify or quantify the unknowns in a sample, using a precursor and product or fragment ion analysis (MS/MS). Non-directed analysis is mostly performed with an electrospray ionization source and a tandem high-resolution mass spectrometer coupled with high-pressure liquid chromatography, or capillary electrophoresis. Non-directed analysis is mostly used during the discovery phase for the identification and quantification of unknowns and modifications to knowns, using tandem mass spectrometry coupled with liquid chromatography. Data-independent analysis sets an objective to generate the MS/MS information of all precursor m/z values and to use this information as a knowledge base. Non-directed analysis serves several applications in food proteomics.
