Studies on Calcium Ion Selectivity of ZnO Nanowire Sensors Using Ionophore Membrane Coatings

Abstract

Zinc oxide nanorods with 100 nm diameter and 900 nm length were grown on the surface of a silver wire (0.25 mm in diameter) with the aim to produce electrochemical nanosensors. It is shown that the ZnO nanorods exhibit a -dependent electrochemical potentiometric behavior in an aqueous solution. The potential difference was found to be linear over a large logarithmic concentration range (1 M to 0.1 M) using Ag/AgCl as a reference electrode and the response time was less than one minute. In order to adapt the sensors for calcium ion measurements in biological fluids with sufficient selectivity and stability, plastic membrane coatings containing ionophores were applied. These functionalized ZnO nanorods sensors showed a high sensitivity (26.55 mV/decade) and good stability.

Functionalized ZnO nanorod-based selective magnesium ion sensor for intracellular measurements

“…After each dip the electrodes were allowed to dry at room temperature. Finally to condition the microelectrode for selectivity of Mg 2+ , it was dipped into a 10 mM MgCl 2 solution (Asif et al, 2008).…”

Different interfaces to crystalline ZnO nanorods and their applications

“…In addition to these excellent optoelectrical properties, ZnO is bio safe and biocompatible [1, 4, and 7] combined with high electron communication features [8]. This implies that ZnO can be used to measure the electrochemical potential between ZnO/biological tissues interface.…”

Synthesis of ZnO and transition metals doped ZnO nanostructures, their characterization and sensing applications

“…ZnO NRs/NWs are extensively applied in various sensing applications fields, e.g. biosensors [44][45][46][47][48][49][50][51], biomarker [52][53], drug delivery [54][55] , chemical sensors [56][57][58], gas sensors [59][60], pH sensors [61], humidity sensor [62][63][64], UV sensors [65][66][67][68][69], temperature sensors [70][71], and pressure/force/mass/load sensors [72][73][74][75]. Also, the high performances of several types of sensors have been enhanced by utilizing different metals doped ZnO nanorods, e.g.…”