Hollow Carbon Nanorods Modified Screen Printed Electrodes for Sensitive Lactate Biosensing

Abstract

AbstractThis novel work details the development and comprehensive characterization of a highly sensitive and selective lactate biosensor system, leveraging the modification of screen‐printed electrodes (SPEs) with hollow carbon nanorods (HCNs). The HCN synthesis involved a multi‐step procedure utilizing iron (III) oxyhydroxide (β‐FeOOH) nanorods as sacrificial templates. Extensive characterization through field emission scanning electron microscopy (FE‐SEM) and X‐ray diffraction (XRD) substantiated the successful fabrication of HCNs replete with substantial cavities. To assess the efficacy of surface modification, HCNs were applied to SPEs using drop casting and electrodeposition methods, enabling a comparative analysis of these techniques in the context of biosensor systems. Lactate detection was accomplished effectively, revealing a linear range of 1 μM to 300 μM for drop casting and 10 μM to 300 μM for electrodeposition, with corresponding limit of detection (LOD) values of 0.55 μM and 2.8 μM. The biosensor system exhibited exceptional stability, repeatability, and selectivity. Furthermore, real sample analyses employing spiked serum samples demonstrated remarkable accuracy, achieving recoveries of up to 109 % for drop casting and 111 % for electrodeposition methods. In summary, the presented HCN‐modified SPEs offer a highly sensitive, selective, and stable platform for lactate detection, showcasing their significant potential across a spectrum of applications, including clinical diagnostics and bioprocess monitoring.