Disposable Prussian blue-anchored electrochemical sensor for enzymatic and non-enzymatic multi-analyte detection

Abstract

The interest in sustainable and low-cost materials for the production of new sensing platforms has been increasing over the time. The possibility of obtaining reliable sensors, on a large scale, easy-to-produce, and cost-effective allows for the development of analytical devices with adequate characteristics for point-of-care analysis. In this context, we present the development of a new low-cost and easy-to-produce disposable electrochemical device composed of a conductive ink modified with Prussian blue for the detection of uric acid, hydrogen peroxide, and glucose. The electrode surface was characterized by scanning electron microscopy coupled with energy dispersive spectroscopy, Fourier-transform infrared spectroscopy, and cyclic voltammetric techniques. Also, the proposed sensors and biosensors were applied for the electrochemical determination of uric acid, hydrogen peroxide, and glucose. The device achieved a linear response ranging from 5.0 to 150.0 μmol L−1 for uric acid, with a limit of detection of 0.70 μmol L−1 using differential pulse voltammetry. The detection of hydrogen peroxide and glucose was performed using amperometry at a working potential of −0.3 V, which. Hydrogen peroxide sensing presented a linear range varying from 100.0 to 800.0 µmol L−1, with a LOD of 31.6 μmol L−1. A glucose biosensor was developed after modification of the electrode with a film composed of chitosan, glutaraldehyde, and glucose oxidase, which presented a linear range varying from 50.0 to 500.0 μmol L−1, with a LOD of 9.20 μmol L−1. Also, the construction of a 3D printed wearable wristband was proposed facing uric acid determination, to show the versatility of the sensor.