Applications Of Inductively Coupled Plasma Mass Spectrometry And Ambient Ionization Mass Spectrometry In Biological Samples

Mass spectrometry is an analytical method with great contribution in the field of analytical scientific testing and certification.According to different research objects,it can be divided into inorganic mass spectrometry and organic mass spectrometry.In recent years,with the deepening of scientific research and the development of ambient ionization technology,mass spectrometry imaging has gradually become a new field of molecular imaging technology and attracted much attentions.Therefore,mass spectrometry has been widely applied in many fields,such as food safety,life science,environmental analysis,geological,and other fields.Especially,the detection of biological samples(e.g.9 body fluid,hair,tissue of animals;flower,leaf,stem,root of plants and microorganism)have great significance for human social activities,which were one of research hotspots in the field of analytical science.Hence,in this dissertation,an inorganic mass spectrometry technology and a self-built ambient ionization source which combined with the organic mass spectrometry were developed for the detection of biological samples.Related works are briefly described as follows:1.Based on the optimized ICP-MS platform combined with multivariate analysis,diagnostic models of esophageal squamous cell carcinoma(ESCC)tissues were established using principal component analysis(PCA)and partial least squares discriminant analysis(PLS-DA),which showing excellent classification of cancerous and non-cancerous group by metallomic profiling.Elemental concentrations of 10 elements showed significant difference(p<0.001)in tumor and non-tumor tissues.It was the first study to evaluate the association of tissue elemental concentrations with ESCC and the results confirmed the considerable potential of elemental studies for biomedical purposes.2.An ambient ionization source of pulsed discharge which coupled with time-of-flight mass spectrometry was developed for direct detection and mass spectrometry imaging for pesticide residues in crops.With pulsed discharge ambient ionization source,direct detection of micro-molecular organics containing C,H,O,N have been achieved.Moerover,mass spectrometry imaging providing visualized spatial distribution information of analytes on crops,intuitively showing that pesticide residues were degraded with the increase of time.The pulsed discharge ambient ionization source has the merits of fast analysis speed,direct sample surface analysis and no complicated sample pretreatment etc.