Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400030, China; Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA.
Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400030, China.
Biosens Bioelectron. 2016 Nov 15;85:935-942. doi: 10.1016/j.bios.2016.05.094. Epub 2016 May 31.
A novel biosensor for rapid, sensitive and selective monitoring of p-nitrophenyl substituted organophosphate pesticides (OPs) in aqueous system was developed using a functional nanocomposite which consists of elastin-like-polypeptide-organophosphate hydrolase (ELP-OPH), bovine serum albumin (BSA), titanium dioxide nanofibers (TiO2NFs) and carboxylic acid functionalized multi-walled carbon nanotubes (c-MWCNTs). ELP-OPH was simply purified from genetically engineered Escherichia coli based on the unique phase transition of ELP and thus served as biocatalyst for OPs, while BSA was used to stabilize OPH activity in the nanocomposite. TiO2NFs was employed to enrich organophosphates in the nanocomposite due to its strong affinity with phosphoric group in OPs, while c-MWCNTs was used to enhance the electron transfer in the amperometric detection as well as for covalent immobilization of ELP-OPH. ELP-OPH/BSA/TiO2NFs/c-MWCNTs nanocomposite were systematically characterized using field emission scanning electron microscopy (SEM), Raman spectra, Fourier Transform infrared spectroscopy (FTIR) and X-ray Diffraction (XRD). Under the optimized operating conditions, the ELP-OPH/BSA/TiO2NFs/c-MWCNTs based biosensor for OPs shows a wide linear range, a fast response (less than 5s) and limits of detection (S/N=3) as low as 12nM and 10nM for methyl parathion and parathion, respectively. Such excellent sensing performance can be attributed to the synergistic effects of the individual components in the nanocomposite. Its further application for selectively monitoring OPs compounds spiked in lake water samples was also demonstrated with good accuracy. These features indicate that the developed nanocomposite offers an excellent biosensing platform for rapid, sensitive and selective detection of organophosphates compounds.
一种新型的生物传感器，用于快速、灵敏和选择性监测水相中对硝基苯基取代的有机磷农药（OPs），是使用一种由弹性蛋白样多肽-有机磷水解酶（ELP-OPH）、牛血清白蛋白（BSA）、二氧化钛纳米纤维（TiO2NFs）和羧酸功能化多壁碳纳米管（c-MWCNTs）组成的功能纳米复合材料开发的。ELP-OPH 是基于 ELP 的独特相变从基因工程大肠杆菌中简单纯化的，因此用作 OPs 的生物催化剂，而 BSA 用于稳定纳米复合材料中的 OPH 活性。TiO2NFs 由于其与 OPs 中的磷酸基团的强亲和力，用于在纳米复合材料中富集有机磷，而 c-MWCNTs 用于增强安培检测中的电子转移以及 ELP-OPH 的共价固定。使用场发射扫描电子显微镜（SEM）、拉曼光谱、傅里叶变换红外光谱（FTIR）和 X 射线衍射（XRD）系统地表征了 ELP-OPH/BSA/TiO2NFs/c-MWCNTs 纳米复合材料。在优化的操作条件下，基于 ELP-OPH/BSA/TiO2NFs/c-MWCNTs 的 OPs 生物传感器具有宽线性范围、快速响应（小于 5s）和检测限（S/N=3），对甲基对硫磷和对硫磷的检测限分别低至 12nM 和 10nM。这种优异的传感性能可归因于纳米复合材料中各成分的协同作用。还进一步展示了其对湖泊水样中添加的 OPs 化合物的选择性监测的应用，具有良好的准确性。这些特点表明，所开发的纳米复合材料为快速、灵敏和选择性检测有机磷化合物提供了一个极好的生物传感平台。
