中文摘要：

在碳纳米管（CNTs）和K3Fe（CN）6修饰的铂电极上吸附固定胆碱氧化酶,以鲁米诺为发光试剂,研制了胆碱电化学发光（ECL）生物传感器。CNTs可有效提高电极表面的电荷传输能力、提高电极表面的生物相容性和对酶分子的固载能力;K3Fe（CN）6对酶活性具有激活作用,同时对H2O2增敏的鲁米诺ECL有增强作用,均有利于提高传感器的检测灵敏度。研究表明,将CNTs分散液与K3Fe（CN）6混合,滴涂修饰在Pt电极上,吸附固定胆碱氧化酶,制备传感器。此传感器在含有8×10-6mol/L鲁米诺的磷酸盐缓冲液（pH7.4）、30℃条件下产生的ECL强度与胆碱浓度在1×10-7～4×10-3mol/L范围内呈线性关系,相关系数为0.994,检出限为1.2×10-8 mol/L。此生物传感器应用于鼠血样中胆碱的测定,测得结果为2.68 mg/L,平均回收率为101.1%。传感器具有快速、稳定和重现性好等特点,有望应用于常规分析。

英文摘要：

An electrochemiluminescent（ECL） choline biosensor was developed by drop-coating of choline oxidase（ChOx） onto a carbon nanotubes（CNTs）/potassium ferricyanide modified platinum electrode with ECL of luminol as readout signal.Due to the improvement of biocompatibility and electron transfer of electrode surface from CNTs,meanwhile the activation for enzyme and the ECL emission from K3Fe（CN）6,the developed biosensor possesses excellent analytical properties.The biosensor gives optimal results while the Pt electrode was modified with 4 μL of 0.33 g/L CNTs dispersoid,2μL of 0.1 mol/L K3Fe（CN）6 and 1.5 U of ChOx.In the PBS buffer（pH 7.4） containing 8×10-6mol/L luminol,the ECL signal linearly responded the concentration of choline from 1×10-7mol/L to 4×10-3mol/L（r=0.994） with detection limit of 1.21×10-8mol/L under 30 ℃ of detection temperature.The developed biosensor was applied to assay the concentration of choline in rat blood sample.The result of 0.268 mg/100 mL was obtained with average recovery of 101.1%.It shows a fast response to choline with good reproducibility.