کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
867364 | 909782 | 2012 | 7 صفحه PDF | دانلود رایگان |

Interest in the fabrication of micro/nanoreactors for evaluation of the function of biomolecules in biological processes, enzymatic reaction kinetics occurring inside the nanospace is rapidly increasing. With a simple reverse-micelle microemulsion method, horseradish peroxidase (HRP), a model biomolecule, was herein skillfully confined in silica nanoshells (HRP@SiO2) and its biocatalytical behaviors were investigated in detail. Spectroscopic measurements showed that the entrapped HRP molecules retained their native structure and had high enzymatic activity toward 3,3′,5,5′-tetramethylbenzidine (TMB) with Michaelis constant (Km) of 3.02 × 10−5 mol L−1. The entrapped HRP displayed a good direct electron transfer behavior and sensitive electrocatalytic response toward the reduction of H2O2, which could be enhanced using thionine and o-phenylenediamine (o-PD) as electron mediators. When using thionine as mediator, the mass transport between the substrates in electrolyte and HRP confined in silica nanospheres through the mesoporous tunnels was slower than that of o-PD, which slowed down the electron transfer between heme in HRP in the confined nanospace and the electrode, and resulted in low sensitivity to H2O2 with thionine as mediator when compared to o-PD.
► Evaluation of the basic behaviors of biomolecules in nanospace is very important for the development of life science.
► A facile strategy for fabrication of nanoreactor was conducted by skillful confining of HRP in silica nanoshells with a reverse-micelle microemulsion method.
► The entrapped HRP molecules retained their native structure and had high enzymatic activity toward TMB.
► The entrapped HRP displayed a good direct electron transfer behavior and sensitive electrocatalytic response toward the reduction of H2O2.
► The slower mass transport resulted in low sensitivity to H2O2 with thionine as mediator when compared to o-PD.
Journal: Biosensors and Bioelectronics - Volume 35, Issue 1, 15 May 2012, Pages 101–107