Gelb, Michael HMasi, Sophia2018-07-312018-07-312018Masi_washington_0250E_18556.pdfhttp://hdl.handle.net/1773/42247Thesis (Ph.D.)--University of Washington, 2018Newborn screening has been an important public health tool for over fifty years. As technology improves, new testing has developed for rare diseases including lysosomal storage disorders (LSDs) in parallel with novel treatment advances. With the discovery of a specific substrate, we have developed the first mass spectrometry-based assay for lysosomal acid lipase (LAL) and a concurrent fluorescent assay. We also have shown that mass spectrometry provides a higher analytical range for three mucopolysaccharidoses (MPS): MPS Types II, IVA, and VI. With increased analytical range via mass spectrometry, we are able to further newborn screening and diagnostic testing with the newly supported option of multiplexing for all four of these LSDs.application/pdfen-USnoneBiochemistryMedicineChemistryThesis