Direct surface sampling of dried blood spots coupled with mass spectrometry for haemoglobin analysis

Edwards, Rebecca Louise (2013). Direct surface sampling of dried blood spots coupled with mass spectrometry for haemoglobin analysis. University of Birmingham. Ph.D.

Preview

Edwards13PhD.pdf
PDF - Accepted Version
Download (4MB)

Abstract

Haemoglobinopathies are inherited disorders, typically detected during neonatal healthcare screening programmes. Haemoglobinopathies are characterised by either a reduction in the synthesis of the globin chains or by point mutations in the globin gene often leading to a single amino acid substitution in the globin chain. Current screening techniques analyse samples from resolubilised dried blood spots (DBS) by HPLC and/or isoelectric focusing. These methods are characterised by lengthy sample preparation and/or ambiguous variant determination. Further analysis is required for unequivocal diagnosis. The work presented here describes a method for the unambiguous diagnosis of haemoglobin variants in neonatal DBS samples using a surface sampling technique called liquid extraction surface analysis (LESA) coupled with high resolution top-down mass spectrometry. LESA allows DBS samples to be sampled directly and the material recovered to be directly electrosprayed into a mass spectrometer. Both the sampling and MS/MS (CID/ETD) parameters were optimised to yield maximum globin chain sequence coverage (up to 81 %) allowing for the unambiguous diagnosis of common Hb variants such as HbS and so-called unknown variants (variants unable to be diagnosed during the standard screening protocol). The LESA sampling technique has also successfully been applied to study Hb non-covalent interactions.

Type of Work:

Thesis (Doctorates > Ph.D.)

Award Type:

Doctorates > Ph.D.

Supervisor(s):