Electrochemical biointerfaces based on carbon nanotubes-mesoporous silica hybrid material: Bioelectrocatalysis of hemoglobin and biosensing applications

RIVAS, GUSTAVO; VILLALONGA, REYNALDO; EGUÍLAZ, MARCOS

BIOSENSORS & BIOELECTRONICS

ELSEVIER ADVANCED TECHNOLOGY

Año: 2018 vol. 111 p. 144 - 151

0956-5663

We are reporting a novel biosensing platform based on a hybrid nanomaterial that combines the advantages ofNafion-coated multiwalled carbon nanotubes (MWCNTs) and mesoporous silica MCM41 nanoparticles functio-nalized with hemoglobin (Hb). MWCNTs-MCM41-Hb hybrid bioconjugate was characterized by scanning elec-tron microscopy (SEM), UV?vis spectroscopy and electrochemical techniques after deposition at glassy carbonelectrodes (GCE). The combination of the high surface area, biocompatibility and protein loading capacity ofMCM41 nanoparticles and the high surface area and catalytic properties of MWCNTs allowed the direct electrontransfer (DET) between Hb and the electrode surface. The electron transfer rate constant (k) and the surfacecoverage of electroactive Hb (ΓHb) were 5.2 s−1and 4.7 × 10−10mol cm−2, respectively. The GCE modifiedwith the nanostructured architecture (GCE/MWCNTs-MCM41-Hb) was successfully used as a third-generationbiosensor for the highly sensitive and selective quantification of nitrite (NO2-) and trichloroacetic acid (TCA) bytaking advantage of the excellent biocatalytic activity of Hb and the efficient direct charge transfer of the hemegroup