基于石墨烯的丁酰胆碱酯酶传感器法快速测定水产品中的孔雀石绿

Preparation of Graphene-based Butyrylcholinesterase Biosensors for the Rapid Determination of Malachite Green in Sea Foods

摘要:

本文以壳聚糖（Chitosan）和石墨烯GS为复合修饰材料，通过交联技术固定化丁酰胆碱酯酶（BuChE）制备了BuChE/CS/GS/GCE纳米酶传感器，建立了一种快速而灵敏测定水产品中孔雀石绿（Malachite Green，MG）的方法。研究了BuChE/CS/GS/GCE纳米酶传感器修饰材料、电解质、固定酶量、抑制时间等对酶传感器响应电流的影响，优化了酶传感器法测定MG的试验条件，结果如下：修饰材料CS与GS之比为1:2、0.10 mol/L的PBS为电解质、pH 7、抑制时间为11 min、酶活是4.0 U/mL。在此条件下，该酶传感器的响应电流与电解质溶液中MG的浓度在1.0×10-7~1.1×10-6 mol/L范围内成线性关系（Ip=-6.97 C MG+22.81，R2=0.9885），最低检测限为2.80×10-8 mol/L（S/N=3），加标回收率在96.36%~99.78%。该方法用于水产品中MG的测定具有简捷、灵敏度高、选择性好、稳定性好、重复性好等优点，用于水产品中孔雀石绿的快速检测是可行的。

Abstract:

Graphene-based butyrylcholinesterase biosensors were prepared utilizing chitosan (CS) and graphene nanosheets (GS) composites to immobilized butyrylcholinesterase (BuChE) on the glass carbon electrode by crosslinking technology, the rapid and sensitive method for the determination of malachite Green (MG) in sea foods was developed. Effects of biosensor modified materials, electrolyte solution, enzyme activity and inhibition time on response current of enzyme biosensor were investigated. The optimum analytical parameters for determination of Malachite Green were determined as follows:the ratio of CS to GS was 1:2, the electrolyte solution was 0.1 mol/L PBS, the pH was 7, the inhibition time was 11 min, and the enzyme activity was 4.0 U/mL. Under optimum conditions, the response currents of the enzyme biosensor had a good linear relationship with MG concentration with a detection range from 1.00×10-7 mol/L to 1.10×10-6 mol/L. The linear equation was Ip=-6.97CMG+22.805 (R2=0.9885), with the limit of detection (LOD) as 2.80×10-8 mol/L (S/N=3). The addition standard recovery of the developed method was 96.36% to 99.78%. The developed method is simple, rapid and sensitive with good selectivity and excellent repeatability, which is practicable for rapid determination of MG or LMG in sea foods.