电化学生物传感器 2009

Superior long-term stability of a glucose biosensor based on inserted barrel plating gold electrodes.

Biosensors & bioelectronics Hsu CT, Hsiao HC, Fang MY, Zen JM
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组成图示

Superior long-term stability of a glu... 传感器构成示意图

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传感器类型

电化学生物传感器

检测对象

葡萄糖(glucose);样品基质:标准葡萄糖溶液、毛细血管血、静脉血/血浆

检测原理

血样经亲水膜进入试纸反应空间后,葡萄糖与固定于桶镀金电极表面的葡萄糖氧化酶(GOx)接触。GOx催化葡萄糖氧化,其辅基FAD被还原为FADH2;铁氰化钾(K3[Fe(CN)6])作为电子介体接受FADH2的电子并被还原,随后在电极表面发生可逆氧化还原,将电子传递至金电极。该过程产生与葡萄糖浓度成正比的安培电流,仪器在约8 s内输出血浆等效血糖值。传感器未采用HCR、RCA或CRISPR-Cas等核酸放大策略,主要依靠酶催化与介体电子传递实现信号转换。

检测灵敏度

测试浓度: 3 mM、5 mM、10 mM、20 mM;临床回归: y = 0.99x + 0.04 mM (lot 21A), y = 0.99x + 0.27 mM (lot 22A);99% CI slope: 0.96–1.01;r > 0.99

效应效果

BPAuE在40 ℃加速老化6个月总体偏差3.3%(摘要报告3.4%),优于VDPdE 5.4%和SPCE 16.2%;25 ℃下分别为3.7%、4.0%、6.3%。40、50、70 ℃ 27天精密度测试中,BPAuE变异系数1.4%–2.4%,VDPdE在70 ℃由2.2%升至8.0%,SPCE由2.8%升至5.7%。25 ℃ 2.5年(911天)测试中,3–20 mM读数稳定,3 mM未偏离±20%,5–20 mM未偏离±10%。164例临床样本误差网格A区98.8%和98.2%,A+B区100%,r>0.99。试纸需1.4 μL血样、8 s出结果,作者称无干扰效应,适合长期血糖控制。

传感器的构成

  • 基底:注射成型塑料基底(injection-molding plastic base),承载电极与试剂层。
  • 换能电极:桶镀金电极(BPAuE,直径1.145 mm),插入塑料基底,提供电化学换能界面。
  • 生物试剂层:葡萄糖氧化酶(GOx,48.5%)、铁氰化钾(K3[Fe(CN)6],8.5%)与非反应成分(43%)一步涂覆,GOx催化葡萄糖,铁氰化钾介导电子传递。
  • 反应膜:亲水膜(hydrophilic film)覆盖试纸,形成微小反应空间,控制血样接触与反应。

中文摘要

一次性血糖试纸广泛用于糖尿病诊断与管理,但性能差异较大。本文系统评估了基于桶镀金电极(BPAuE)的葡萄糖试纸长期稳定性,并与气相沉积钯电极(VDPdE)和丝网印刷碳电极(SPCE)平台比较。在40 ℃加速老化6个月实验中,BPAuE葡萄糖生物传感器在5–20 mM葡萄糖浓度下平均偏差为3.4%,稳定性最佳。在40、50和70 ℃下27天的精密度测试中,其变异系数仅为1.4%–2.4%,表现最优。误差网格分析显示所有测量点均落在A区和B区;回归分析表明该传感器与参考方法在99%置信水平下无显著差异。该安培型葡萄糖生物传感器由两个桶镀金电极插入注射成型塑料基底,再固定生物试剂层和膜制成,在25 ℃下长期稳定性可达2.5年。结果表明,葡萄糖氧化酶/桶镀金电极平台适合长期准确血糖控制。

英文摘要

Disposable one shot usage blood glucose strips are routinely used in the diagnosis and management of diabetes mellitus and their performance can vary greatly. In this paper we critically evaluated the long-term stability of glucose strips made of barrel plating gold electrodes. Compared to other glucose biosensing platforms of vapor deposited palladium and screen printed carbon electrodes, the proposed glucose biosensor was found to show the best stability among the three biosensing platforms in thermal acceleration experiments at 40 degrees C for 6 months with an average bias of 3.4% at glucose concentrations of 5-20 mM. The precision test of this barrel plating gold glucose biosensor also showed the best performance (coefficients of variation in the range of 1.4-2.4%) in thermal acceleration experiments at 40 degrees C, 50 degrees C and 70 degrees C for 27 days. Error grid analysis revealed that all measurements fell in zone A and zone B. Regression analysis showed no significant difference between the proposed biosensor and the reference method at 99% confidence level. The amperometric glucose biosensor fabricated by inserting two barrel plating gold electrodes onto an injection-molding plastic base followed by immobilizing with a bio-reagent layer and membrane was very impressive with a long-term stability up to 2.5 years at 25 degrees C. Overall, these results indicated that the glucose oxidase/barrel plating gold biosensing platform is ideal for long-term accurate glycemic control.

关键词

葡萄糖生物传感器桶镀金电极葡萄糖氧化酶长期稳定性血糖监测安培检测