Direct electron transfer and electrocatalysis of hemoglobin adsorbed on mesoporous carbon through layer-by-layer assembly.
Using chitosan as an effective linker between CMK-3 and glassy carbon electrode surface, {Hb/CMK-3}n multilayer film-modified electrodes were constructed through layer-by-layer assembly. The morphology of thus-formed {Hb/CMK-3}n film was characterized by scanning electron micrographs, and the interaction of hemoglobin (Hb) with CMK-3 was studied by UV-vis spectroscopy and electrochemical methods. Under optimal conditions, {Hb/CMK-3}6 film showed a couple of stable and well-defined redox peaks at about -377 and -296 mV in pH 7.0 buffers. Furthermore, the {Hb/CMK-3}6 film displayed excellent electrocatalysis to the reduction of both H2O2 and O2. Based on thus-formed film and its direct electron transfer behavior, a novel biosensor was presented for the determination of H2O2 ranging from 1.2 to 57 muM with the detection limit of 0.6microM at S/N=3. CMK-3 provided a desirable matrix for protein immobilization and biosensor preparation.
Feng
Jiu-Ju
JJ
The Key Lab of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093, China.
Xu
Jing-Juan
JJ
Chen
Hong-Yuan
HY
D000327:Adsorption; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D004563:Electrochemistry; D004566:Electrodes; D004579:Electron Transport; D006454:Hemoglobins / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D016062:Porosity; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
D006454:Hemoglobins; D002244:Carbon