比較不同奈米金球在電極表面修飾的模式於過氧化氫的反應

Abstract

在食品工業上，過氧化氫經常用於食品漂白、微生物的控制及無菌包裝上。長期食用，可能導致健康傷害。為了確認奈米金球修飾於碳膠電極表面，對於測定過氧化氫反應的影響。首先在碳膠電極表面以電化學方式，重氮化一層4-aminophenylacetic acid (CMA)於電極表面。隨後，將奈米金球或表面已修飾過的奈米金球，以物理吸附或共價鍵結於CMA電極上。將奈米金球修飾後的碳膠電極，經由循環伏安法(cyclic voltammetry)、定電位測定法(current-time responses)量測溶液中過氧化氫的反應。碳膠電極、奈米金球修飾後的碳膠電極，以及半胱胺奈米金球修飾後的碳膠電極，測量出過氧化氫的電流訊號值為7.94 x 10-6, 1.41 x 10-5, 1.44 x 10-5 A/cm2/mM， 結果顯示奈米金球修飾後碳膠電極確實可以增加過氧化氫的電化學訊號。

In the food industry, hydrogen peroxide was often used for food bleaching、microbiological control and aseptic packaging. Long-term consumption may cause health damage. To verify the effect of gold nanoparticle modification on screen-printed carbon paste electrode (SPCE) in the detection of hydrogen peroxide (H2O2) SPCE was first functionalized by electrochemical diazotization to deposit a layer of 4-aminophenylacetic acid (CMA) on the surface of SPCE. Subsequently, the gold nanoparticles (AuNPs) or the surface modified AuNPs were coated on top of the CMA layer by either physical absorption or covalent bonding. The capability of the gold nanoparticles-modified SPCE to detect hydrogen peroxide in solution was investigated by cyclic voltammetry and current-time responses. The sensitivity of SPCE, SPCE modified with AuNPs and cysteamine-coated AuNPs to H2O2 was 7.94 x 10-6, 1.41 x 10-5, 1.44 x 10-5 A/cm2/mM. The results showed that the modification of SPCE with gold nanoparticles markedly increased the electrochemical response to H2O2.