INSTRUMENTAL ADVANCES IN CAPILLARY ELECTROPHORESIS MASS SPECTROMETRY FOR TRACE-SENSITIVE PROTEOMICS

Abstract

Proteomics plays a pivotal role in modern biology by qualitatively and quantitatively characterizing the proteome of biological systems and holistically reflecting the overall dynamics and heterogeneity in organisms. Capillary electrophoresis mass spectrometry (CE-MS) serves as a powerful analytical tool for proteomics and offers superior resolution and minimal sample consumption, yet its adoption has been limited by historical gaps in instrumental development. This dissertation progresses CE-MS proteomics by developing instrumentation and methodologies to promote sensitivity, robustness, scalability, automation, and throughput to facilitate analyses of low-amount proteome samples. The works in this dissertation achieved advances including detection of peptides at sub-picomolar levels (30 zmol), robust analysis of 100 nL proteome samples, and levitational sample enrichment by 4.4 folds. Collectively, this dissertation contributes to the leaping development of CE-MS for proteomics.Chapter 1 overviews the background, current state and challenges of capillary electrophoresis mass spectrometry proteomics and explains research motivation. Chapter 2 introduces methodology combining large-volume sample stacking (LVSS) CE and trapped ion mobility spectrometry (TIMS) for ultra-high-sensitive analysis of low-abundance peptides from mouse brain tissues. Chapter 3 presents a robotic CE-MS system (RoboCap) achieving robust and reproducible analysis of minimal sample volume of proteome. Chapter 4 details an acoustic levitational sample enrichment method for trace-amount proteome. Chapter 5 summarizes the research outcomes in this dissertation and provides potential directions to further improve CE-MS proteomics.