Rapid Analysis Of Biomolecules By Using Ambient Mass Spectrometer

Mass spectrometry is widely used in metabonomics,proteomics,clinical medicine and food safety as a useful analytical tool because of its high sensitivity and rapidity of respond.The relative molecular mass can be obtained through the full scan mode of mass spectrometry and the structural information can be got via tandem mass spectrometry analysis.Traditionally it is necessary for some samples to have pretreatment before mass spectrometry analysis due to its complex matrix or less structural information in tandem mass spectrometry analysis.However,most traditional pretreatment methods are time-consuming and complicated in operation steps,so they can not satisfy the demand of rapid detection of samples by mass spectrometry.Due to their various sample introduction approaches,ambient ion sources are beginning to be combined with sample pretreatment.In this thesis,we had developed three rapid analytical methods by using ambient ion source for analysis of a series of biological samples.The main contents of the thesis are as follows.1.Probe-electrospray ionization was developed by coupling a SPME probe.The SPME probe was modified with TiO₂ via sol-gel method.The SPME probe is simple in operation and the eluent can be directly detected by nanoESI-MS for the phosphoproteome analysis.The method has been demonstrated excellent selectivity and sensitivity for enrichment of phosphopeptides in complex biological samples.2.Ion-transmission mass spectrometry?MS?was proposed for coupling with PADs to enable rapid in situ MS analysis of the sample on paper.The sample was analyzed directly on paper via analyte ionization by ions transmitted through the paper,generated by a low-temperature plasma probe.Prior to MS analysis,the sample can be separated by paper electrophoresis or by paper chromatography,among a variety of other features offered by PADs.The versatility of this technique was demonstrated by MS analysis of a paper microarray,a mixture of amino acids and whole blood doped with drugs on PADs.3.A new method was developed for identification C=C location by coupling epoxidation reaction.The C=C in unsaturated fatty acids were reacted with LTP probe and produces abundant diagnostic ions indicative of the C=C location were obtained upon collision induced dissociation?CID?.The almost quantitative transformation of unsaturated FAs makes the developed method especially attractive for the accurate quantitation of simple FA mixtures by using epoxide intensities.This analytical capability was succes sfully demonstrated by analyzing unsaturated FAs extracted from human plasma.