Okpara Enyioma C, Nde Samuel Che, Fayemi Omolola E, Ebenso Eno E
Department of Chemistry, School of Physical and Chemical Sciences, Faculty of Natural and Agricultural Sciences, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735, South Africa.
Material Science Innovation and Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735, South Africa.
Nanomaterials (Basel). 2021 May 14;11(5):1294. doi: 10.3390/nano11051294.
The need for constant assessment of river water qualities for both aquatic and other biological survival has emerged a top priority, due to increasing exposure to industrial pollutants. A disposable screen print carbon electrode was modified with a conductive polymer (PANI) and Zn and/or Cu oxides NPs, obtained through bioreduction in citrus peel extracts (lemon and orange), for ultra-sensitive detection of PB, in the Crocodile River water sample. The synthesized materials were characterized with Fourier-transform infra-red spectroscopy (FTIR), ultra-violet visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM). The SPC-modified electrodes designated as SPCE/LPE/BiONPs/PANI and SPCE/OPE/BiONPs/PANI were characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) and eventually deployed in the electrochemical detection of PB in water using square wave voltammetry (SWV) technique. The electrochemical responses of the modified electrodes for both CV and EIS in 0.1 M HCl demonstrated enhanced performance relative to the bare SPCE. A detection and quantification limit of 0.494 ppb and 1.647 were obtained at SPCE/LPE/BiONPs/PANI, respectively, while a detection and quantification limit of 2.79 ppb and 8.91 ppb, respectively, were derived from SPCE/OPE/BiONPs/PANI. The relative standard deviations (RSD) for SPC electrode at a 6.04 µM PB analyte concentration was 4.76% and 0.98% at SPCE/LPE/BiONPs/PANI and SPCE/LPE/BiONPs/PANI, respectively. The effect of copper, zinc, iron, cobalt, nickel, and magnesium on the stripping peaks of PB at SPCE/OPE/BiONPs/PANI, showed no significant change except for cobalt, with about 17.67% peak current drop. The sensors were assessed for possible determination of PB in spiked river water samples. The average percentage recovery and RSD calculated were 94.25% and 3.74% ( = 3) at SPCE/LPE/BiONPs/PANI and, 96.70% and 3.71% ( = 3) at SPCE/OPE/BiONPs/PANI, respectively. Therefore, the fabricated sensor material could be used for environmental assessment of this highly toxic heavy metal in the aquatic system.
由于工业污染物暴露的增加，持续评估河流水质以保障水生生物和其他生物的生存已成为当务之急。通过在柑橘皮提取物（柠檬和橙子）中进行生物还原获得的导电聚合物（聚苯胺，PANI）以及锌和/或铜氧化物纳米颗粒修饰了一次性丝网印刷碳电极，用于超灵敏检测鳄鱼河水样中的铅（PB）。合成材料通过傅里叶变换红外光谱（FTIR）、紫外可见光谱（UV-Vis）和扫描电子显微镜（SEM）进行表征。将指定为SPCE/LPE/BiONPs/PANI和SPCE/OPE/BiONPs/PANI的SPC修饰电极使用循环伏安法（CV）和电化学阻抗谱（EIS）进行表征，并最终采用方波伏安法（SWV）技术用于水中铅的电化学检测。在0.1 M HCl中，修饰电极对于CV和EIS的电化学响应相对于裸SPCE表现出增强的性能。在SPCE/LPE/BiONPs/PANI上分别获得了0.494 ppb的检测限和1.647的定量限，而在SPCE/OPE/BiONPs/PANI上分别得到了2.79 ppb和8.91 ppb的检测限和定量限。在6.04 µM铅分析物浓度下，SPCE/LPE/BiONPs/PANI和SPCE/LPE/BiONPs/PANI处SPC电极的相对标准偏差（RSD）分别为4.76%和0.98%。铜、锌、铁、钴、镍和镁对SPCE/OPE/BiONPs/PANI上铅的溶出峰的影响，除钴外无显著变化，钴使峰电流下降约17.67%。对传感器进行了加标河流水样中铅的可能测定评估。在SPCE/LPE/BiONPs/PANI处计算得到的平均回收率和RSD分别为94.25%和3.74%（n = 3），在SPCE/OPE/BiONPs/PANI处分别为96.70%和3.71%（n = 3）。因此，所制备的传感材料可用于水生系统中这种剧毒重金属的环境评估。
