Miniaturized Biosensing System for Electrochemical Tear Lactate Detection

Lactateis an important biomarker in the field of medical rehabilitation and sports health monitoring and can indicate a number of diseases or muscle fatigue. Tears are a noninvasive and potentially sampling medium, so it is important to have an accurate test for tear lactate. The aim of this paper is to design a biosensing system for electrochemical detection of tear lactate for rapid and accurate detection of lactate concentration in tear fluid. For this purpose, we modified the interdigital electrode sensor using nickel oxide nanoparticles and perfluorinated resin, and applied an excitation voltage to the interdigital electrode through a self-developed constant potential circuit, and then quantitatively detected tear lactate by detecting the response current generated on the sensor. For the detection of lactic acid in tears, linear concentration ranges of 0.1-1 mM and 1–30 mM were observed. The device has the advantages of easy operation, fast response and low detection cost, and is expected to be widely used in sports health and disease diagnosis.