李艷彩,莫韜
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李艷彩,莫韜
(漳州師范學(xué)院 化學(xué)與環(huán)境科學(xué)系,福建 漳州 363000)
圖1 不同膜電極在0.1 mol/L pH值6.9的PBS緩沖溶液中 的循環(huán)伏安曲線,掃速為100mV/s
圖2是Hb/AgNPs/Nafion膜電極在不同掃速下的循環(huán)伏安曲線. 隨著掃速的增大,Hb直接電子傳遞的陰極峰和陽極峰電位變化很小,說明該過程的電子傳遞速度較快. 由圖3可知:掃速范圍20~600mV/s,氧化峰和還原峰電流均與掃速成線性關(guān)系,這說明電極表面的氧化還原反應(yīng)是由表面控制的過程,電活性質(zhì)點在沒有物質(zhì)傳遞控制下實現(xiàn)轉(zhuǎn)化. 電位負(fù)向掃描時,膜中電活性[HbFe(III)]被還原成了[HbFe(II)];電位正向掃描時,膜中電活性[HbFe(II)]被氧化成了[HbFe(III)].
圖2 不同掃速下,Hb/AgNPs/Nafion膜電極在0.1 mol/LpH值6.9的PBS緩沖溶液中的循環(huán)伏安曲線
圖3 陰極峰電流和陽極峰電流與掃速的關(guān)系
圖4 pH值對Hb/AgNPs/Nafion膜電極電位的影響(掃速100 mv/s)
圖5 掃速100 mv/s,不同膜電極對的電催化還原(pH值4.5的HAc緩沖溶液)
圖6 0.1 mol/L不同pH值的HAc緩沖溶液中,Hb/AgNPs/Nafion膜電極的循環(huán)伏安曲線(2 NO? 濃度為6.0 mmol/L,掃速為100 mV/s)
圖7 濃度對Hb/AgNPs/Nafion膜電極的 影響(pH=4.5的HAc緩沖溶液)
圖8 10 mL 0.05 mol/LpH=4.5的HAc緩沖溶液中, Hb/AgNPs/Nafion膜電極對催化電流隨1時間變化的響應(yīng)曲線
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[責(zé)任編輯:熊玉濤]
Building Biosensors by Immobilizing Hemoglobin and Silver Nanoparticles and Using Nafion Membrane
LIYan-cai,MOTao
(Chemistry and Environmental Science Department, Zhangzhou Teachers College,
Hemoglobin (Hb) and silver nanoparticles (AgNPs) are immobilized to the surface of glassy carbon electrode by using Nafion membrane. Cyclic voltammetry experiments show that Hb/AgNPs/ Nafion film electrode in pH 6.9 PBS buffer solution has a pair of significant HbFe (Ⅲ)/(Ⅱ) oxide reduction peak and has a good catalytic response to of nitrite. The linear range is 2.0×10-5-3.4×10-4mol/L (=18,=0.997) and the detection limit is 1.2×10-6mol/L (=3). Therefore, the membrane electrode can be used as nitrite biosensor.
1006-7302(2010)03-0006-14
O657.1
A
2010-03-25
福建省教育廳科技項目(JA09163);漳州師范學(xué)院科研基金資助項目(L20779)
李艷彩(1980—)女,河南省葉縣人,講師,博士,主要從事電分析化學(xué)研究,E-mail: liyancai2000@yahoo.com.cn.