TiO_(2)/聚乙烯醇纳米复合材料电化学检测雨水径流中微量抗生素研究

TiO_(2)/polyvinyl alcohol nanocomposite electrochemical detection of trace antibiotics in rainwater runoff

针对雨水中抗生素污染问题,开发了基于TiO_(2)/聚乙烯醇(PVA)纳米复合材料电化学检测技术,以期解决传感器存在的检测限较低、检测范围较窄等问题。通过SEM和XRD技术研究TiO_(2)/PVA纳米复合材料的形貌和结构性能,结果显示制备的TiO_(2)纳米颗粒均匀分布在PVA的结构中。循环伏安法结果显示TiO_(2)/PVA纳米复合物对四环素的检测具有高稳定性和响应性。采用微分脉冲伏安法探究TiO_(2)/PVA玻璃碳电极作为四环素传感器的电化学性能,结果表明该复合材料具有检测限低(0.03μmol/L)、灵敏度高(0.8183μA/(μmol·L))和线性范围广(1~140μmol/L)的优势。该传感器可有效检测出实际雨水中的四环素,表明其在实际雨水检测中具有较高的应用前景。

Considering the antibiotic pollution in rainwater,an electrochemical detection technology based on TiO_(2)/polyvinyl alcohol(PVA)nanocomposite materials was developed to solve the problems of low detection limit and narrow detection range of existing sensors.First,a TiO_(2)/PVA powder sample was prepared.The prepared powder sample(1 mg)was ultrasonically dispersed in dimethyl sulfoxide(5 mL).Then dipcoating technology was used to prepare nanocomposite GCE electrodes.Finally,the clean pretreated GCE was immersed in the dimethyl sulfoxide powder sample solution,and dissolved in water after a certain period of time to remove the weakly bound particles,and a TiO_(2)/PVA GCE electrode was obtained.The morphology and structural properties of the TiO_(2)/PVA nanocomposite were studied by SEM and XRD measurements,and the results showed that the prepared TiO_(2) nanoparticles were uniformly distributed in the PVA structure.In addition,the addition of TiO_(2) nanoparticles reduced the intensity of the basic peak of PVA,which led to an increase in the degree of amorphousness of the composite material.Cyclic voltammetry(CV)results showed that the peak current of the TiO_(2)/PVA GCE electrode was 23μA,which is much greater than the 8μA of the PVA electrode,indicating that the TiO_(2)/PVA GCE composite electrode had a higher electrochemical reaction activity for tetracycline,and TiO_(2)/PVA nanocomposite has high stability for the detection of tetracycline.After 50 tests,the anode peak current of the PVA electrode decreased from 8.1μA to 4.7μA(a decrease of about 42.0%),while the TiO_(2)/PVA GCE electrode only decreased from 22.8μA to 19.7μA(a decrease of about 13.6%).Using differential pulse voltammetry(DPV)to explore the electrochemical performance of TiO_(2)/PVA GCE(as a tetracycline sensor),the results showed that the composite material had a low detection limit(0.04μmol/L),high sensitivity(0.8183μA/(μmol·L)),and wide linear range(1140μmol/L).Finally,the sensor can effectively detect tetracycline in actual rainwater,indicating that it has a higher application prospect in actual rainwater detection.