Dept Nanoengineering, UCSD, La Jolla, CA 92093, USA.
Analyst. 2009 Aug;134(8):1614-7. doi: 10.1039/b902171j. Epub 2009 May 15.
We demonstrate the first example of using potentiometry at ion-selective electrodes (ISEs) for probing in real-time monitoring of biometallization processes. A copper ISE is used for real-time monitoring of the NADH-mediated reduction of copper in the presence of gold nanoparticle seeds. Such potentiometric detection of NADH is not susceptible to surface fouling common with analogous amperometric measurements of this co-factor. Biosensing of ethanol is illustrated in the presence of alcohol dehydrogenase and NAD(+), along with potentiometric detection of the NADH product at the copper ISE. The concept can be readily expanded to the monitoring of various biometallization processes in connection to different enzymatic transformations and ISE, and used for ultrasensitive detection of bioaffinity interactions in connection to common enzyme tags.
我们展示了首例使用离子选择性电极（ISE）中的电位法来实时监测生物金属化过程的实例。铜 ISE 用于实时监测在金纳米颗粒种子存在下，NADH 介导的铜还原。与类似的该辅因子的电流测量相比，这种对 NADH 的电位检测不易受到常见的表面污垢的影响。在存在乙醇脱氢酶和 NAD(+)的情况下，演示了对乙醇的生物传感，同时在铜 ISE 上对 NADH 产物进行了电位检测。该概念可以很容易地扩展到与不同酶转化和 ISE 相关的各种生物金属化过程的监测，并用于与常见酶标签相关的生物亲和相互作用的超灵敏检测。
