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Statistical Analysis of the Main Effects and Interaction Effects of Detection of Hydrogen Peroxide for
the Carbon Paste Electrode Modified with Copper Hexacyanoferrate
Chia-Cheng Hsiao (蕭佳政) , Chung-Min Lien (連崇閔) , Hau Lin (林浩)
Department of Chemical and Materials Engineering, Southern Taiwan University
南台科技大學化學工程與材料工程系
ABSTRACT
The glucose and oxygen can be catalyzed by the glucose oxidase and the glucose is oxidized to gluconic acid and the oxygen is reduced to hydrogen peroxide. The responding current of hydrogen peroxide is detected in
the phosphate buffer solution(PBS) and then the concentration of the hydrogen peroxide can be obtained and consequently, the concentration of the glucose can be determined. The Cu(Ⅱ)HCF can be used to modify the
carbon paste electrode because the Cu(Ⅱ)HCF possesses the excellent catalytic characteristic and it can be used with the graphite carbon powders and carbon paste to make the carbon paste electrode [Cu(Ⅱ)HCF :
graphite carbon powders = 3 : 7(weight ratio)] to elevate the responding current of the hydrogen peroxide. The results showed that the responding current for the carbon paste electrode modified with Cu(Ⅱ)HCF was
elevated significantly. A study of experimental design involving three factors (operating potential, stirring rate, and pH value of PBS) and two levels was performed to analyze the main effects and interaction effects of
reaction parameters on the average responding current of detection of hydrogen peroxide for the carbon paste electrode modified with Copper(Ⅱ) Hexacyanoferrate(Cu(Ⅱ)HCF). The results showed that the main effects
of operating potential, stirring rate, and pH value of PBS were 0.498 µA , 0.040 µA , and -0.461 µA respectively.
INTRODUCTIO
N
※Three Electrodes System：
Working
Electrode
Pt
Ag/AgCl
Due to hydrogen peroxide is widely used in the industry and food preservation, developing a
hydrogen peroxide sensor which can detect the hydrogen peroxide rapidly and conveniently is an
important research subject. In recent years, diabetes has become one of the top ten causes of death for
the people in Taiwan. Therefore developing a rapid and convenient glucose biosensor also has become
an important research subject. Because the copper(Ⅱ) hexacyanoferrate possesses the excellent
catalytic characteristic it can be used with the carbon paste and graphite carbon powders which
possess the excellent conductivity to make the carbon paste electrode and to elevate the responding
current of the hydrogen peroxide. The carbon paste electrode is used to detect the responding current
of hydrogen peroxide in phosphate buffer solution (PBS) and the concentration of hydrogen peroxide
can be determined from the responding current of hydrogen peroxide.
Counter
Electrode
Reference
Electrode
N2
pH 7.4之0.05 M PBS
Buffer Solution
RESULTS AND DISCUSSION
Fig 2. CV graphs for (A) carbon paste
electrode modified with copper
hexacyanoferrate (the range of scanning
potential: -0.8～+0.8 V) (B) unmodified
carbon paste electrode( the range of scanning
potential: -0.6～+0.6 V)
Temperature at
30℃
Table 1 Three factors and two levels of the
factorial design
Fig 1. The theory of detection of glucose for the biosensor
EXPERIMENTAL
Preparation of Copper(Ⅱ) Hexacyanoferrate(Cu(Ⅱ)HCF) ：
3(CuSO4．5H2O)+ 2〔K3[Fe(CN)6]〕
Cu3[Fe(CN)6]2 +3K2SO4 +15H2O
Coprecipitation method：
：
Stoichiometry 3
2
(mole ratio)
Separation of side product
Table 2 The reaction conditions of the
experimental design
Table 3 Algebraic signs for calculating effects
of the 23 factorial design
Drying at 60℃ (48 hours)
CuSO4 ． 5H2O(aq)
(MERCK）
K3Fe(CN)6(aq)（MERCK）
Cu3[Fe(CN)6]2 (aq)
Preparation of the working electrode :
copper(Ⅱ)
hexacyanoferrate
1.
Surface area of
electrode=0.0805cm2
7 cm
Table 4 The results of the average responding
current of the sixteen experiments for detection
of hydrogen peroxide
0.05
cm
0.5 cm
2. Then the Copper(Ⅱ) Hexacyanoferrate powders, graphite carbon powders and carbon paste were
mixed with the appropriate ratio (Copper(Ⅱ) Hexacyanoferrate : graphite carbon powders : carbon paste
= 0.3 : 0.7 : 1). After the mixing was complete, the mixture was evenly coated on the nake-ended electric
wire and dried in the oven and then we obtained the carbon paste electrode.
The mixing of
Cu(Ⅱ)HCF
and carbon
powders was
even.
Mixing with
equal amount of
carbon paste
銅
芯
電
線
Table 5 The effects for detection of the average
responding current of hydrogen peroxide for
the carbon paste electrode modified with
copper hexacyanoferrate
CONCLUSIONS
The Cu(Ⅱ)HCF was used to modify the carbon paste electrode because the Cu(Ⅱ)HCF
possessed the excellent catalytic characteristic and it could be used with the graphite carbon powders
and carbon paste to make the carbon paste electrode [Cu(Ⅱ)HCF : graphite carbon powders = 3 :
7(weight ratio)] to elevate the responding current of the hydrogen peroxide. A study of experimental
design involving three factors (operating potential, stirring rate, and pH value of PBS) and two levels
was performed to analyze the main effects and interaction effects of reaction parameters on the
average responding current of detection of hydrogen peroxide for the carbon paste electrode
modified with Copper(Ⅱ) Hexacyanoferrate(Cu(Ⅱ)HCF). The results showed that the main effects
of operating potential, stirring rate, and pH value of PBS were 0.498 µA, 0.040 µA, and -0.461 µA
respectively. The results showed that the main effect of pH value of PBS was negative and the order
of the significant level for main effects was operating potential > pH value of PBS > stirring rate.
REFERENCES
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2. Miao, Y. ; Tan, S. N., Analytica Chimica Acta, 2001, 437, 87-93.
3. Kim, M. A. ; Lee, W.-Y., Analytica Chimica Acta, 2003, 479, 143-150.
4. Xu, Y. ; Hu, C. ; Hu, S., Sensors and Actuators B, 2008, 130, 816-822.