Department of Analytical Chemistry, Faculty of Chemistry, University College of Science, University of Tehran, P.O. Box 14155-6455, Tehran, Iran.
Department of Analytical Chemistry, Faculty of Chemistry, University College of Science, University of Tehran, P.O. Box 14155-6455, Tehran, Iran.
Talanta. 2019 Mar 1;194:415-421. doi: 10.1016/j.talanta.2018.10.040. Epub 2018 Oct 17.
An ultrasensitive and highly selective voltammetric sensor with ultra-trace level detection limit is introduced for RDX determination in water samples. The sensing platform is the nano-sized molecularly imprinted polymer (nano-MIP)/MWCNTs nanocomposite, casted on glassy carbon electrode (GCE). The MIP was synthesized by copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of RDX via precipitation polymerization. The MIP was characterized by scanning electron microscopy (SEM) and fast fourier transform infrared spectroscopy (FT-IR). It was demonstrated that the MIP, coated on the electrode, have the capability to adsorb RDX and increase its related voltammetric signal. This capability was remarkably lower, for the non-imprinted polymer (NIP)-based electrode. The MIP-based electrode signal to RDX is greatly enhanced in the presence of MWCNTs. The sensor showed excellent selectivity to RDX, compared to similar compounds of HMX and TNT. It exhibited two dynamic linear ranges including 0.1-10.0 nmol L and 0.01-1.00 µmol L. The detection limit and relative standard deviation of the sensor were calculated to be 20 pmol L(3S/m, first curve) and 4.5% (10 nmol L, n = 5), respectively. The utility of the sensor was checked for RDX analysis in water samples which led to satisfactory results.
本文介绍了一种用于水样中 RDX 测定的超灵敏和高选择性的伏安传感器，具有痕量检测限。传感平台是纳米尺寸的分子印迹聚合物（nano-MIP）/MWCNTs 纳米复合材料，铸在玻碳电极（GCE）上。MIP 通过 RDX 存在下的甲基丙烯酸和乙二醇二甲基丙烯酸的共聚作用，通过沉淀聚合合成。MIP 通过扫描电子显微镜（SEM）和快速傅里叶变换红外光谱（FT-IR）进行了表征。结果表明，涂覆在电极上的 MIP 具有吸附 RDX 并增加其相关伏安信号的能力。对于基于非印迹聚合物（NIP）的电极，这种能力明显较低。在 MWCNTs 的存在下，基于 MIP 的电极对 RDX 的信号大大增强。与 HMX 和 TNT 等类似化合物相比，该传感器对 RDX 表现出优异的选择性。它显示出两个动态线性范围，包括 0.1-10.0 nmol L 和 0.01-1.00 µmol L。传感器的检测限和相对标准偏差分别计算为 20 pmol L（3S/m，第一曲线）和 4.5%（10 nmol L，n=5）。该传感器用于水样中 RDX 的分析，结果令人满意。
