Sharma Anshu, Baral Dinesh, Rawat Kamla, Solanki Pratima R, Bohidar H B
Special Centre for Nanosciences, Jawaharlal Nehru University, New Delhi-110067, India. School of Physical Science, Jawaharlal Nehru University, New Delhi-110067, India.
Nanotechnology. 2015 May 1;26(17):175302. doi: 10.1088/0957-4484/26/17/175302. Epub 2015 Apr 8.
We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe(3)O(4))) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe(3)O(4) and CA-Fe(3)O(4)/ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe(3)O(4), CA-Fe(3)O(4) nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe(3)O(4)) and 189.51 nm (CA-Fe(3)O(4)) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe(2)O(3)/ITO immunosensor exhibits a good detection range of 12.5-500 ng mL(-1) with a low detection limit of 0.32 ng mL(-1), sensitivity 0.03 Ω/ng ml(-1) cm(-2), and reproducibility more than 11 times.
我们报告了有关制备用于霍乱弧菌检测的高效免疫传感器的研究。通过共沉淀法合成了磁铁矿（四氧化三铁（Fe(3)O(4)））纳米颗粒（NPs），并用柠檬酸（CA）进行了包覆。这些纳米颗粒通过电泳沉积在氧化铟锡（ITO）涂层的玻璃基板上，并用于固定抗霍乱弧菌单克隆抗体（Ab）和牛血清白蛋白（BSA），以使用电化学技术检测霍乱弧菌。通过X射线衍射（XRD）、透射电子显微镜（TEM）、傅里叶变换红外（FTIR）光谱和动态光散射（DLS）技术对Fe(3)O(4)和CA-Fe(3)O(4)/ITO进行了结构和形态研究。获得的Fe(3)O(4)、CA-Fe(3)O(4)纳米颗粒的平均晶体尺寸分别约为29±1nm和37±1nm。通过DLS测量发现纳米颗粒的流体动力学半径为77.35nm（Fe(3)O(4)）和189.51nm（CA-Fe(3)O(4)）。所制备的BSA/Ab/CA-Fe(2)O(3)/ITO免疫传感器的电化学响应研究结果显示，其检测范围为12.5-500ng mL(-1)，检测限低至0.32ng mL(-1)，灵敏度为0.03Ω/ng ml(-1) cm(-2)，重现性超过11次。
