Electrochemical Detection of Vibrio cholerae by Amine Functionalized Biocompatible Gadolinium Oxide Nanoparticles

Herein, we report the biocompatible amine-functionalized gadolinium oxide nanoparticles (Gd(2)O(3) NPs) for the possibility of electrochemical detection of Vibrio cholerae (Vc) cells. The microwave irradiation process is applied to synthesize Gd(2)O(3) NPs. The amine (NH(2)) functionalization is carried out via overnight stirring with 3(Aminopropyl)triethoxysilane (APTES) at 55 °C. The size of NPs amine functionalized APETS@Gd(2)O(3) NPs are determined by transmission electron microscopy (TEM). APETS@Gd(2)O(3) NPs are further electrophoretically deposited onto indium tin oxide (ITO) coated glass substrate to obtain working electrode surface. The monoclonal antibodies (anti-CT) specific to cholera toxin associated to Vc cells are covalently immobilized onto the above electrodes using EDC-NHS chemistry and further BSA is added to obtain the BSA/anti-CT/APETS@Gd(2)O(3)/ITO immunoelectrode. Further, this immunoelectrode shows the response for cells in CFU range from 3.125 × 10(6) to 30 × 10(6) and is very selective with sensitivity and LOD 5.07 mA CFUs mL cm(−2) and 0.9375 × 10(6) CFU respectively. To establish a future potential for APTES@Gd(2)O(3) NPs in field of biomedical applications and cytosensing, the effect of APTES@Gd(2)O(3) NPs on mammalian cells is also observed using in vitro cytotoxicity assay and cell cycle analysis.