Department of NanoEngineering, University California San Diego, La Jolla, CA 92093, USA.
Talanta. 2010 Apr 15;81(1-2):15-9. doi: 10.1016/j.talanta.2009.11.029. Epub 2009 Nov 13.
The influence of the bending-induced mechanical stress of flexible Nafion/GOx/carbon screen-printed electrodes (SPEs) upon the performance of such glucose biosensors has been examined. Surprisingly, such flexible enzyme/polymer-SPEs operate well following a severe bending-induced mechanical stress (including a 180 degrees pinch), and actually display a substantial sensitivity enhancement following their mechanical bending. The bending-induced sensitivity enhancement is observed only for the amperometric detection of the glucose substrate but not for measurements of hydrogen peroxide, catechol or ferrocyanide at coated or bare SPEs. These (and additional) data indicate that the bending effect is associated primarily with changes in the biocatalytic activity. Such sensitivity enhancement is more pronounced at elevated glucose levels, reflecting the bending-induced changes in the biocatalytic reaction. Factors affecting the bending-induced changes in the performance are examined. While our data clearly indicate that flexible enzyme/polymer-SPEs can tolerate a severe mechanical stress and hold promise as wearable glucose biosensors, delivering the sample to the active sensor surface remains the major challenge for such continuous health monitoring.
研究了柔性 Nafion/GOx/碳丝网印刷电极（SPE）的弯曲诱导机械应力对这种葡萄糖生物传感器性能的影响。令人惊讶的是，这种柔性酶/聚合物-SPE 在受到严重的弯曲诱导机械应力（包括 180 度挤压）后仍能良好运行，并且在机械弯曲后实际上显示出显著的灵敏度增强。这种弯曲诱导的灵敏度增强仅在安培检测葡萄糖底物时观察到，而在涂覆或未涂覆 SPE 时测量过氧化氢、儿茶酚或亚铁氰化物时则没有。这些（和其他）数据表明，弯曲效应主要与生物催化活性的变化有关。在较高的葡萄糖水平下，这种灵敏度增强更为明显，反映了生物催化反应中的弯曲诱导变化。研究了影响性能的弯曲诱导变化的因素。虽然我们的数据清楚地表明，柔性酶/聚合物-SPE 可以承受严重的机械应力，并有望成为可穿戴葡萄糖生物传感器，但向活性传感器表面输送样品仍然是这种连续健康监测的主要挑战。
