Development of simplified quantitative method for tryptic digested C-reactive protein by using online SPE coupled to triple quadrupole mass spectrometer

Method development for accurate quantification of biomarker protein is very important step for the researchers in pharmaceutical industries and clinical fields. Mass spectrometry based quantitative proteomics approach shows a big potential to be the substitution of ELISA due to its precision, accuracy and multiplexing capability. In order to achieve the required sensitivity and selectivity, nano scale liquid chromatography mass spectrometry or sample preparation method including depletion of dominant protein and/or enrichment of target protein are frequently used. In this study, we tried to develop simple and high sensitive quantification method for C reactive protein (CRP), the level of which rise as a result of inflammation etc., by using online SPE coupled to triple quadrupole mass spectrometer without any complicated sample enrichment and depletion.