In-Situ Direct Electrochemistry of Hemoglobin Using Vertically Aligned Carbon Nanotube Ropes

摘要: Direct electrochemistry of hemoglobin (Hb) is usually implemented by immobilizing it on the electrode. In-situ determination Hemoglobin little bit tough due to slow electron transfer in solution phase owing its complex structure. In this study, we report in-situ direct using vertically aligned single walled carbon nanotubes (SWNTs) ropes indium tin oxide (ITO) platform. Morphological characterization SWNTs accomplished optical surface profiler, FE-SEM and AFM. Electrochemical impedance spectroscopy (EIS) SWNT/ITO electrode reveals reduction 'charge resistance' for comparison ITO. Exchange current density increases tenfold (5.4 × 10-2 A cm-2 while standard rate constant hundred times (1.2 10-4 C2s-1 after vertical alignment ITO sur- face. Cyclic voltammetry (CV) Hb demonstrates increase currents SWNT immobilization. Kinetic studies CV revel controlled nature reaction that attributed concentration molecules close proximity electrode, which turn negatively charged carboxyl ends nanotubes. Moreover, a plausible mechanism peak acidic pH range also presented clearly role oxygen containing groups at nanotube from hemoglobin. Sensitivity sensor determined both lyophilized present red blood cells (RBCs) separated whole blood. It found be 21.2 μAμM-1 8.94 μAdLg-1 respectively. Lower detection limit 10 nM. After successful demonstration (CNTs) hemoglobin, electrodes can used routine clinical samples RBCs.