A novel molecularly imprinted polymer for the selective removal of interfering hemoglobin prior to whole blood analysis

Abstract

A novel, selective, sensitive, cheap and robust hemoglobin imprinted polymer (Hb-MIP) in the form of a powder, was synthesised through bulk, free-radical polymerization employing molecular imprinting technology (MIT), for the selective removal of interfering hemoglobin from whole blood samples prior to instrumental analysis in molecular diagnostics and toxicological assays. Following solid phase extraction clean-up through batch rebinding experiments, the Hb-MIP powder effectively removed hemoglobin from whole blood samples as demonstrated by the UV-Vis absorbance reductions from as high as 0.794 Au to lower values of 0.193 Au. It also proved to be efficient by optimally removing hemoglobin within 18 min. Experimentally, the powder showed good selectivity towards hemoglobin as demonstrated by the percentage removal efficiency of 76%, even in the presence of analogous species such as chlorophyll with a negligible percentage removal efficiency of about 32%. Furthermore, the Hb-MIP powder was compared to a commercially available and expensive interferents removing material, graphitized carbon black (GCB) powder that is not selective, as shown by almost the same percentage removal efficiencies of 96% and 91%, for hemoglobin and chlorophyll, respectively. The synthesized Hb-MIP powder in this thesis presented itself as an efficient, selective, cheap and non-destructive whole blood clean-up pre-analytical tool that with further research may replace the conventional whole blood cleanup strategies that are currently employed in molecular diagnostics and toxicological assays such as the common, inefficient and destructive centrifugation.