TY - JOUR
T1 - A simple strategy for the immobilization of catalase on multi-walled carbon nanotube/poly (L-lysine) biocomposite for the detection of H2O2 and iodate
AU - Ezhil Vilian, A. T.
AU - Chen, Shen Ming
AU - Lou, Bih Show
PY - 2014/11/15
Y1 - 2014/11/15
N2 - Herein, we report a novel third-generation H2O2 and IO3- biosensor, which was fabricated by loading catalase (CAT) onto l-lysine/multiwalled carbon nanotube (PLL/f-MWCNT) film modified glassy carbon electrode (GCE). The UV-visible (UV-vis) and Fourier-transform infrared (FTIR) spectra show that the catalase encapsulated in the PLL/f-MWCNT film can effectively retain its bioactivity. The immobilized CAT retained its bioactivity with a high protein loading of 4.072×10-10molcm-2, thus exhibiting a surface-controlled reversible redox reaction, with a fast heterogeneous electron transfer rate of 5.48s-1. The immobilized CAT shows a couple of reversible and well-defined cyclic voltammetry peaks with a formal potential (E0) of -0.471V (vs. Ag/AgCl) in a pH 6.5 phosphate buffer solution (PBS). Moreover, the modified film exhibited high electrocatalytic activity for the reduction of hydrogen peroxide (H2O2). It exhibited a wide linear response to H2O2 in the concentration range of 1×10-6-3.6×10-3, with higher sensitivity (392mAcm-2M-1) and a lower Michaelis-Menten constant (0.224mM). It provided high-catalytic activity towards H2O2 in a shorter time (5s), with a detection limit of 8nM. These results indicate great improvement in the electrochemical and electrocatalytic properties of the CAT/PLL/f-MWCNT biosensor, offering a new idea for the design of third-generation electrochemical biosensors.
AB - Herein, we report a novel third-generation H2O2 and IO3- biosensor, which was fabricated by loading catalase (CAT) onto l-lysine/multiwalled carbon nanotube (PLL/f-MWCNT) film modified glassy carbon electrode (GCE). The UV-visible (UV-vis) and Fourier-transform infrared (FTIR) spectra show that the catalase encapsulated in the PLL/f-MWCNT film can effectively retain its bioactivity. The immobilized CAT retained its bioactivity with a high protein loading of 4.072×10-10molcm-2, thus exhibiting a surface-controlled reversible redox reaction, with a fast heterogeneous electron transfer rate of 5.48s-1. The immobilized CAT shows a couple of reversible and well-defined cyclic voltammetry peaks with a formal potential (E0) of -0.471V (vs. Ag/AgCl) in a pH 6.5 phosphate buffer solution (PBS). Moreover, the modified film exhibited high electrocatalytic activity for the reduction of hydrogen peroxide (H2O2). It exhibited a wide linear response to H2O2 in the concentration range of 1×10-6-3.6×10-3, with higher sensitivity (392mAcm-2M-1) and a lower Michaelis-Menten constant (0.224mM). It provided high-catalytic activity towards H2O2 in a shorter time (5s), with a detection limit of 8nM. These results indicate great improvement in the electrochemical and electrocatalytic properties of the CAT/PLL/f-MWCNT biosensor, offering a new idea for the design of third-generation electrochemical biosensors.
KW - Biosensor
KW - Catalase
KW - Direct electrochemistry
KW - Multiwall carbon nanotubes
UR - http://www.scopus.com/inward/record.url?scp=84902981797&partnerID=8YFLogxK
U2 - 10.1016/j.bios.2014.05.023
DO - 10.1016/j.bios.2014.05.023
M3 - Article
C2 - 24967754
AN - SCOPUS:84902981797
SN - 0956-5663
VL - 61
SP - 639
EP - 647
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
ER -