Nonenzymatic Glucose Sensors Based on Nanoporous Copper Thin Films Fabricated by Laser-Induced Photoreduction

Diabetes, a chronic metabolic disease affecting millions of people worldwide, necessitates the development of low-cost and reliable nonenzymatic glucose sensors for effective diabetes management on a global scale. This paper presents an approach using laser processing to fabricate nonenzymatic glucose sensors based on nanoporous Cu thin films (CuTFs). By subjecting a CuO nanorod array to a laser-induced photoreduction (LIPR) process, a highly efficient and sensitive glucose sensor is achieved through the transformation into a nanoporous CuTF. The nanoporous CuTF-based glucose sensor exhibits exceptional sensitivity, with a response of approximately 2.2 mA mM^-1 cm^-2, and an impressively low detection limit of 0.025 μM. Furthermore, the sensor demonstrates remarkable stability, retaining 96% of its initial current response throughout a comprehensive 15-day evaluation. Additionally, the sensor exhibits excellent selectivity, effectively distinguishing glucose from interfering substances, such as ascorbic acid or uric acid, thereby establishing its reliability for glucose-sensing applications. Furthermore, the CuTF-based glucose sensor is applied to a human sweat-based noninvasive glucose sensor. The utilization of the LIPR process for fabricating the nanoporous CuTF holds great potential in advancing the field of advanced glucose-sensing technologies.