Fast quantitative analysis of metabolic biomarkers for clinical screening using mass spectrometry
Abstract
The utilization of mass spectrometry (MS) in clinical biomarker screening is undergoing considerable expansion. MS is powerful in identifying different compounds in biological samples with high specificity and high sensitivity in a high-throughput manner. Sampling and ionization is the most diverse and key process that affect the efficiency, sensitivity and practicability for analyzing biological samples using mass spectrometry. Collection of blood samples using cellulose-based paper card is a standard and effective process in neonatal screening and is being explored for therapeutic drug analysis. In comparison with liquid blood sample, dried blood spots (DBS) on paper cards are convenient for transportation and analytes are shown to be more stable for a longer storage. In addition, a much smaller volume of blood is sufficient for several replicate analyses; this is of significant advantage for infants and critically ill patients as blood collected by finger pricks or heel pricks, instead of venipuncture, can fulfill the requirement. The analysis of DBS on paper cards using MS still require a complex multi-step procedure of sample treatment, involving punching a paper disk containing the samples, extracting samples using solvent, purifying the analytes, and chromatography separation. Paper spray as an integrated sampling and ionization technique was invented recently in our group. Paper spray generates ions directly from the samples on the paper substrate by applying solvent and high voltage, which serves as a simple way for direct clinical biomarker screening using MS without the need for complex sample preparation and separation. This single step technique can be applied for quantitatively analyzing multiple compounds and is expected to become a fast, simple, effective and in-expensive route for clinical biomarker screening. The research and development includes a series of steps, including a systematical study of the paper spray ionization mechanism, design of disposable sample cartridge, selection of the proper biomarkers, and improvement of the method for quantitative analysis. The methodology developed is to be applied clinical screening of biomarkers for newborn screening. Finally, a proof-of-concept prototype of high-throughput paper spray device was built for direct and fast analysis of raw biological samples.
Degree
Ph.D.
Advisors
Ouyang, Purdue University.
Subject Area
Analytical chemistry|Biomedical engineering
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.