NFC-enabling smartphone-based portable amperometric immunosensor for hepatitis B virus detection

A smartphone-controlled electrochemical sensor operated entirely via Near Field Communication (NFC) was used to create a simple label-free immunoassay for detecting Hepatitis B Virus (HBV). The completed system was composed of a card-sized electrochemical NFC tag sensor integrated with a smartphone and antibody-modified electrode sensor. Screen-printed graphene electrodes (SPGE) were modified with gold nanoparticles, increasing high sensitivity while beta-cyclodextrin (beta-CD) was electropolymerized on the surface to capture antibodies. The modification and immobilization processes were verified by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The NFC-based electrochemical immunosensor was then used to quantify Hepatitis B surface antigen (HBsAg) using amperometric detection by measuring the current from the (Fe(CN)(6))(3-/4-) redox couple before and after addition of HBsAg. The linear calibration curve and limit of detection for HBsAg were found to be 10-200 mu g/mL and 0.17 mu g/mL, respectively. The sensor was then tested with chronic HBV infected serum samples and the system showed a good correlation with traditional immunoassays. This electrochemical immunosensor has the potential to be an alternative platform for portable, simple, sensitive and selective tools that can readily assess a variety of health indicators using a low-cost sensor system operated from a smartphone.

Automated summary

An NFC-operated electrochemical sensor controlled by a smartphone was developed for detecting HBV, showing high sensitivity and accuracy. The sensor has a great potential as a portable and cost-effective tool for assessing health indicators with the convenience of smartphone operation.