Method Development for Qualitative and Quantitative Study in Mass Spectrometry

Abstract

Mass spectrometry has become the method of choice for lots of areas in recent years including protein study and clinical research. In this thesis, work from three projects covering three very different domains in the big area of mass spectrometry has been described. Chapter 2 to Chapter 4 presented the project of methodology development in chemical derivatization of peptides. In this project, custom-tunable tags prepared through solid phase synthesis increased sequence coverage of peptide ions in electron transfer dissociation for de novo sequencing, thus simplifies the characterization of proteins. Additionally, the application of developed stable isotopic tags pair can be used for quantitation of the proteins as well as for the simplified characterization of proteins. Chapter 5 presented the project of newborn screening in clinical study. In this project, a novel tandem mass spectrometry duplex assay for the clinical diagnosis of neuronal ceroid lipofuscinoses (NCL) has been developed. The duplex assay recognized the deficient patients from healthy newborns by quantification of the enzyme activity in dried blood spot through the use of tandem mass spectrometer. Chapter 6 presented the result from protein-protein interaction project. Protein-protein interaction is essential to understand biological pathways. In this project, a second generation of protein interaction reporter BDD-PIR has been synthesized and applied to proteins for performance evaluation. This molecule has a low molecular weight and high solubility and is therefore expected to have improved performance than the first generation protein interaction reporter for in vivo application.