Designing a novel microfluidic sensor based on Cu(OH)2/Ni(OH)2 core–shell nanostructural arrays on the surface of SPCE as a flow injection amperometric sensor for regular insulin measurement

Abstract

Herein, a novel microfluidic sensor with a small size and low dialysis fluid consumption is designed for continuous insulin measurement. The sensor is based on core–shell nanostructures consisting of Ni(OH)2 layers shelled on Cu(OH)2 nanowires which grow on screen-printed carbon electrode (Ni(OH)2/Cu(OH)2@SPCE), which is created through a simple three-step in situ technique. As a result, the sensor illustrated good electron transfer, suitable active surface area, and acceptable electrocatalytic performances. The proposed microfluidic system, including a fluid channel with a depth of about 60 μm, a modified SPCE underneath, and the experiments were carried out pumping the dialysis fluid at the flow rate of 0.3 ml min−1. It resulted in satisfactory reproducibility and acceptable repeatability with a good concentration range of 10–110 pM, considered as an appropriate candidate for practical application due to its little fluid consumption and small channel size.