College of Agronomy, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu 611130, Sichuan, China.
College of Science, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
Mater Sci Eng C Mater Biol Appl. 2020 Dec;117:111264. doi: 10.1016/j.msec.2020.111264. Epub 2020 Jul 6.
In this work, the carbon dots (CDs) were prepared by one-pot hydrothermal method with chitosan as a carbon source and hydrogen peroxide as an oxidant, this route is a novel, simple and green. The prepared CDs has a relatively high photoluminescence (PL) quantum yield (QY) (18.9%) and good water solubility. CdTe quantum dots (CdTe QDs) possess the characteristic of responding to pH rapidly. So a ratiometric fluorescent probe for measuring pH was constructed using the prepared CDs and CdTe QDs. Under the excitation of 330 nm, the probe shows dual (blue and red) emission with peaks at 430 and 600 nm, respectively. When the pH of the solution changes, the blue fluorescence intensity of the CDs remains stable as a reference signal, while the red fluorescence intensity of CdTe QDs changes accordingly. This method has obvious pH-sensitive feature, stable fluorescence properties, and a great linear relationship with pH values in the range of pH 3.0-11.0. What is more, the method can monitor proton-producing enzyme-catalyzed reactions by acting as a ratiometric pH probe.
在这项工作中，通过水热法以壳聚糖为碳源、以过氧化氢为氧化剂制备了碳点（CDs），该方法新颖、简单、绿色。所制备的 CDs 具有相对较高的光致发光（PL）量子产率（18.9%）和良好的水溶性。碲化镉量子点（CdTe QDs）具有快速响应 pH 值的特性。因此，使用所制备的 CDs 和 CdTe QDs 构建了用于测量 pH 值的比率荧光探针。在 330nm 的激发下，探针分别在 430nm 和 600nm 处显示出双（蓝色和红色）发射峰。当溶液的 pH 值发生变化时，作为参考信号的 CDs 的蓝色荧光强度保持稳定，而 CdTe QDs 的红色荧光强度则相应变化。该方法具有明显的 pH 敏感性、稳定的荧光特性，并且在 pH 3.0-11.0 范围内与 pH 值具有很好的线性关系。更重要的是，该方法可以通过作为比率 pH 探针来监测质子产生酶催化反应。
