Department of Analytical Chemistry, College of Chemistry , Jilin University , Changchun , 130012 , China.
Anal Chem. 2019 May 7;91(9):6250-6258. doi: 10.1021/acs.analchem.9b00965. Epub 2019 Apr 26.
Because boron nitride quantum dots (BN QDs) have a wider gap (5.0-6.0 eV) than other QDs, the edge configurations, chemical functionalities, and heteroatom dopants can decrease and regulate the band gap of BN QDs, thereby ameliorating the QDs' properties. Now, the precise control and regulation of BN QDs are still at an early stage and is a challenging task. Therefore, we used thiourea and l-cysteine as different sulfur precursors to regulate the BN QDs' optoelectronic properties in this study. It is interesting that two kinds of S-regulated BN QDs present significantly different electrochemiluminescence (ECL) properties and electro-optical activity. Furthermore, a ratiometric and enzyme-free ECL sensing mode is constructed with the amplified surface plasmon coupled-ECL (SPC-ECL) strategy. The proposed DNA sensor can quantify the BRAF gene from 1 pmol/L to 1.5 nmol/L with a limit of detection (LOD) of 0.3 pmol/L. The change of BN QDs' ECL signal was easily observed with a smartphone camera. This work for the first time provides insight into the role of sulfur regulation in enhancing ECL efficiency and the electro-optical activity of BN QDs.
由于氮化硼量子点（BN QDs）的带隙（5.0-6.0 eV）比其他 QDs 更宽，边缘结构、化学官能团和杂原子掺杂剂可以降低和调节 BN QDs 的带隙，从而改善 QDs 的性质。如今，BN QDs 的精确控制和调节仍处于早期阶段，是一项具有挑战性的任务。因此，我们在这项研究中使用硫脲和 L-半胱氨酸作为不同的硫前体来调节 BN QDs 的光电性质。有趣的是，两种 S 调节 BN QDs 表现出明显不同的电化学发光（ECL）性质和光电活性。此外，构建了一种比率型和无酶的 ECL 传感模式，采用放大的表面等离子体耦合-ECL（SPC-ECL）策略。所提出的 DNA 传感器可以从 1 pmol/L 到 1.5 nmol/L 定量检测 BRAF 基因，检测限（LOD）为 0.3 pmol/L。BN QDs 的 ECL 信号的变化可以用智能手机摄像头轻易观察到。这项工作首次提供了有关硫调节在提高 BN QDs 的 ECL 效率和光电活性方面的作用的见解。
