Direct Electrochemistry of Myoglobin
J. Chin. Chem. Soc., Vol. 58, No. 7, 2011 935
-
concentration in the range from 2.0 to 22.0 mmol L and a
1
was realized. The result can be attributed to the specific
characteristics of IL such as high ionic conductivity and
good biocompatibility that provide a suitable microenvi-
ronment for Mb. The electrochemical behavior of Mb in
the multilayer film was carefully investigated with the elec-
trochemical parameters calculated. The Mb bioelectrode
showed excellent electrocatalytic ability to the reduction of
TCA. So the Mb and IL LBL multilayer film modified elec-
trode provided an efficient platform for the preparation of a
new third generation electrochemical biosensor.
linear regression equation was obtained as Iss(mA) =
4
7.01C (mmol/L) + 3.87 (g = 0.997) with the detection
limit as 0.6 mmol/L (3s), which was smaller than some pre-
3
2,33
vious results,
indicating the proposed Mb bioelectrode
exhibited higher sensitivity to TCAdetection. The apparent
app
Michaelis-Menten constant (K
M
) can be calculated from
the electrochemical version of the Lineweaver-Burk equa-
3
tion:
4
app
1
1
K M
=
Iss Imax Imax
+
c
ACKNOWLEDGEMENTS
where Iss is the steady current after the addition of sub-
strate, c is the bulk concentration of the substrate, and Imax
We are grateful to the financial support of the Natural
Science Foundation of Jiangxi Province (2009GZC0031)
and the S&T plan projects of Jiangxi Provincial Education
Department (GJJ10590).
is the maximum current measured under the saturated sub-
app
strate condition. Based on the above equation the K
M
value was calculated as 21.36 mmol/L, which was smaller
7,35
than some reported values.
1
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1
1
1
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1
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