Nanosensors Based on Modified Carbon Screen-Printed Electrodes for Biochemical Application
Iva Dimitrievska, Anita Grozdanov, Perica Paunovic
Faculty of Technology and Metallurgy, University “Ss Cyril and Methodius”, 1000 Skopje,
Rugjer Boshkovikj 16, North Macedonia
Over the past decade, electrochemical detection of biochemical species using novel nanostructure-based devices has attracted significant attention for chemical, genomics, biomedical diagnostics, and drug discovery applications. The use of nanostructured devices in biochemical sensors in place of conventional sensing technologies has advantages of high sensitivity, low decreased energy consumption and potentially highly miniaturized integration. Owing to their particular structure, excellent electrical properties and high chemical stability, carbon nanotube and graphene based electrical devices have been widely developed for high performance biochemical sensors.
In this study, modified carbon-based screen-printed electrode (graphene and CNTs) were explored as biosensors used in ultrasensitive detection of biochemical entities, such as active pharmaceutical ingredients (APIs) – diclofenac and hydrochlorothiazide. Surface modification was done using polyethylene glycol and polyvinylidene fluoride, applied with drop modification method. Еlectrochemical method such as cyclic voltammetry (CV) is discussed in detail, along with scanning electron microscopy (SEM) and ultraviolet-visible spectroscopy (UV-Vis), as analytical characterization techniques. The electrochemical measurements show that the acidic environment contributes for better redox processes hence modifications show better electrochemical response at low pH. Hydrochlorothiazide shows best results for CNT/PVDF modification due to the synergy of carbon nanostructure and polymer film sensitivity. PVDF-modified graphene SPE show good electrochemical properties and achieve the desired rectangular voltammogram shape, as a result of the outstanding electrical properties of both structures.
Keywords: Biosensors, screen-printed electrodes, carbon nanostructures, polymers, drop modification, cyclic voltammetry, scanning electron microscopy, ultraviolet-visible spectroscopy
This research work is financed by the Austrian – Macedonian bilateral project cooperation, 2022-2023