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

[摘要] 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.

[发布机构] University:University of Birmingham;Department:School of Biosciences

[关键词] Q Science;QH Natural history;QH301 Biology