Microneedles with interdigitated electrodes for in situ impedimetric VEGF sensing

Abstract

Continuous monitoring of protein biomarkers in interstitial fluid (ISF) is essential for improving patient care and outcomes. This study presents a novel electrochemical impedance spectroscopy (EIS) sensor utilizing microneedles (MNs) patterned with interdigitated electrodes for the detection of vascular endothelial growth factor (VEGF). The MNs, are fabricated from flexible polylactide (PLA) using a simple molding technique, followed by metal deposition with an interdigitated pattern to serve as a platform for the EIS sensor. After functionalization with anti-VEGF antibodies, impedance measurements are conducted to detect VEGF levels, demonstrating a significant change in impedance in response to varying concentrations of the target biomarker. The MNs can easily penetrate rat skin by hand, puncturing without mechanical breakage. This innovative approach enhances the sensitivity and specificity of biomarker detection and paves the way for continuous monitoring applications in diagnostics and preventative medicine.