Glucose oxidase-functionalized fluorescent gold nanoclusters as probes for glucose
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- 作者：Xiaodong Xia<sup>asup><sup> ; sup><sup>bsup> ; Yunfei Long<sup>bsup><sup> ; sup><sup>l_yunfei927@163.comsup><sup> ; sup><sup>l_yunfei927@126.comsup> ; Jianxiu Wang<sup>asup><sup> ; sup><sup>jxiuwang@csu.edu.cnsup>
- 关键词：Gold nanocluster ; Glucose oxidase ; Etching chemistry ; Glucose ; Fluorescence
- 刊名：Analytica Chimica Acta
- 出版年：2013
- 出版时间：15 April, 2013
- 年：2013
- 卷：772
- 期：Complete
- 页码：81-86
- 全文大小：860 K
文摘
Creation and application of noble metal nanoclusters have received continuous attention. By integrating enzyme activity and fluorescence for potential applications, enzyme-capped metal clusters are more desirable. This work demonstrated a glucose oxidase (an enzyme for glucose)-functionalized gold cluster as probe for glucose. Under physiological conditions, such bioconjugate was successfully prepared by an etching reaction, where tetrakis (hydroxylmethyl) phosphonium-protected gold nanoparticle and thioctic acid-modified glucose oxidase were used as precursor and etchant, respectively. These bioconjugates showed unique fluorescence spectra (¦Ë<sub>em maxsub> = 650 nm, ¦Ë<sub>ex maxsub> = 507 nm) with an acceptable quantum yield (ca. 7 % ). Moreover, the conjugated glucose oxidase remained active and catalyzed reaction of glucose and dissolved O<sub>2sub> to produce H<sub>2sub>O<sub>2sub>, which quenched quantitatively the fluorescence of gold clusters and laid a foundation of glucose detection. A linear range of 2.0 ¡Á 10<sup>?6sup>-140 ¡Á 10<sup>?6sup> M and a detection limit of 0.7 ¡Á 10<sup>?6sup> M (S/N = 3) were obtained. Also, another horseradish peroxidase/gold cluster bioconjugate was produced by such general synthesis method. Such enzyme/metal cluster bioconjugates represented a promising class of biosensors for biologically important targets in organelles or cells.