Anovelthird-generationhydrogenperoxide(H_2O_2)biosensor(Hb/CdS/MWNTs/GCE)wasfabricatedthroughhemoglobin(Hb)adsorbedontothemercaptoaceticacidmodifiedCdSQDs/carboxylmultiwallcarbonnanotubes'(MWNTs)films.CyclicvoltammogramofHb/CdS/MWNTs/GCEshowedapairofwell-definedandquasi-reversibleredoxpeakswithaformalpotential(E~0)of-0.230V(vs.Ag/AgCl)in0.1mol/LpH=8.0phosphatebuffersolution(PBS),whichwasthecharacteristicoftheHbhemeFe(Ⅲ)/Fe(Ⅱ)redoxcouple.ThebiosensorshowsanexcellentelectrocatalyticactivitytothereductionofH_2O_2.TheresponsetimeofthedesignedbiosensortoH_2O_2atapotentialof-0.30Vwaslessthan2sandlinearrelationshipswereobtainedintheconcentrationrangesof2.0×10~(-6)—2.7×10~(-3)mol/Land2.7×10~(-3)—7.7×10~(-3)mol/Lwithadetectionlimitof3.0×10~(-7)mol/L(S/N=3).TheapparentMichaelis-MentenconstantK_mwasestimatedtobe1.324mmol/LthatillustratedtheexcellentbiologicalactivityofthefixedHb.
