Environmental Research Lab, PG and Research Department of Chemistry, Alagappa Government Arts College, Karaikudi, Tamil Nadu, 630 003, India.
School of Chemistry, Bharathidasan University, Thiruchirapalli, Tamil Nadu, 620024, India.
Mikrochim Acta. 2018 Jan 10;185(2):96. doi: 10.1007/s00604-017-2641-1.
An electrochemical sensor is described for the determination of L-tryptophan (TRP). The method is based on the use of a glassy carbon electrode (GCE) modified with a nanocomposite consisting of moss ball-like cerium-doped ZnO and functionalized multiwalled carbon nanotubes (Ce-ZnO/f-MWCNT). Ce-doped ZnO was synthesized by a low temperature hydrothermal method. The Ce-ZnO/f-MWCNT nanocomposite was characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, FTIR and field emission scanning electron microscopy. The nanocomposite was drop cast on a GCE for use in electrochemical detection of TRP via cyclic voltammetry and differential pulse voltammetry. The oxidation peak current (0.76 V vs. Ag/AgCl) is strongly improved compared to a bare GCE. The experimental parameters such as solution pH value, scan rate, stability, concentration, reproducibility and repeatability were optimized. Response is linear in the 10 to 100 nM TRP concentration range, the limit of detection is 1.2 nM, and the sensitivity is 2.59 μA·nM·cm. The electrode was applied to the determination of TRP in spiked real samples and gave satisfactory results. Graphical abstract Schematic presentation of the preparation of a moss ball like nanocomposite consisting of cerium-doped ZnO and functionalized MWCNTs. cerium-Deposited on a on glassy carbon electrode, it enables nanomolar detection of L-tryptophan by differential pulse voltammetry.
一种电化学传感器，用于测定 L-色氨酸（TRP）。该方法基于使用玻璃碳电极（GCE）修饰，修饰物为由苔藓球状掺铈氧化锌和功能化多壁碳纳米管（Ce-ZnO/f-MWCNT）组成的纳米复合材料。Ce 掺杂 ZnO 通过低温水热法合成。Ce-ZnO/f-MWCNT 纳米复合材料通过 X 射线衍射、拉曼光谱、X 射线光电子能谱、FTIR 和场发射扫描电子显微镜进行表征。将纳米复合材料滴铸在 GCE 上，用于通过循环伏安法和差分脉冲伏安法电化学检测 TRP。与裸 GCE 相比，氧化峰电流（0.76 V 对 Ag/AgCl）得到了显著提高。优化了实验参数，如溶液 pH 值、扫描速率、稳定性、浓度、重现性和重复性。在 10 至 100 nM TRP 浓度范围内呈线性响应，检测限为 1.2 nM，灵敏度为 2.59 μA·nM·cm。该电极被应用于测定加标实际样品中的 TRP，结果令人满意。 图表描述 由掺铈氧化锌和功能化 MWCNTs 组成的苔藓球状纳米复合材料的制备示意图。将铈沉积在玻璃碳电极上，使 L-色氨酸能够通过差分脉冲伏安法进行纳摩尔检测。
