Sensors and Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
CQM-Centro de Química da Madeira, Universidade da Madeira, Campus da Penteada, 9020-105, Funchal, Portugal.
Talanta. 2020 May 15;212:120806. doi: 10.1016/j.talanta.2020.120806. Epub 2020 Feb 3.
Nitrogen and sulphur-doped Carbons Dots (N-CDs and S-CDs) were synthesized by a hydrothermal method and incorporated as surface electrode modifiers to evaluate their properties for electrochemical sensing. The first task was to characterize the synthesized materials, for which different spectroscopies, scanning microscopes, mass spectrometry and elementary analysis were performed. Next, a glassy carbon electrode (GCE) was surface-modified with the doped CDs and applied to check the electrochemical signal of different organic compounds corresponding to different families. Water solubility of the doped carbon dots forced us to incorporate them in a graphite-polystyrene ink to complete the modification of electrodes. This modification needed a first activation to obtain a properly conductive surface. The organic compounds examined were salicylic acid, cysteine and ascorbic acid. The modified GCEs exhibited an enhanced sensitivity, probably caused by the increase of active surface, but in addition, signals of salicylic acid were shifted ca. 200 mV to lower potentials, what is a proof of the increase of the heterogeneous electron transfer rate, and a demonstration of an enhanced catalytic response.
氮硫掺杂碳点（N-CDs 和 S-CDs）通过水热法合成，并作为表面电极修饰剂，以评估其用于电化学传感的性能。首先，通过不同的光谱学、扫描显微镜、质谱和元素分析来对合成材料进行表征。接下来，将掺杂的 CDs 修饰到玻碳电极（GCE）表面，用于检测不同家族的不同有机化合物的电化学信号。掺杂碳点的水溶性迫使我们将其掺入石墨-聚苯乙烯油墨中，以完成电极的修饰。这种修饰需要先进行激活，以获得适当的导电表面。所检测的有机化合物是水杨酸、半胱氨酸和抗坏血酸。修饰后的 GCE 表现出更高的灵敏度，这可能是由于活性表面的增加所致，但此外，水杨酸的信号向更低的电位移动了约 200 mV，这证明了异质电子转移速率的增加，以及对催化响应的增强。
