ABSTRACT
This work presents, silicon carbide nanoparticles (SiCNPs) embedded in a conductive polymer (CP) to be electrospun to fabricate a nanofibrous membrane and a thin-film. Electrochemical enzymatic glucose sensing mechanism of an electrospun nanofibrous membrane (ENFM) of SiCNPs in a CP compared to a spin-coated-thin-film (SCTF) of SiCNPs in a CP. Fiber alignment in the form of a matrix is a key factor that determines the physical properties of nanofiber membrane compared to thin-film. It is found that glucose sensing electrodes formed by a SiCNPs-ENFM has enhanced binding of the glucose oxidase (GOx) enzyme within the fibrous membrane as compared to a SiCNPs-SCTF. The SiCNPs-ENFM and SiCNPs-SCTF glucose sensing electrodes were characterized for morphology by using scanning electron microscopy (SEM) and for electrochemical activity by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) methods. SiCNPs-ENFM based glucose electrodes shown a detection range from a 0.5 mM to 20 mM concentration with a better sensitivity of [Formula: see text]/gmMcm2, and low limit of detection (LOD) 552.89 nM compared to SiCNPs-SCTF with sensitivity of [Formula: see text]/gmMcm2 and LOD of [Formula: see text]. The change in current level with SiCNPs-ENFM was ~14% contrast to ~75% with the SiCNPs-SCTF based glucose sensor over 50 days. The electrochemical analysis results demonstrated that the SiCNPs-ENFM electrode provides enhanced sensitivity, better limit of detection (LOD), and durability compared to SiCNPs-SCTF based glucose sensing electrode.
Subject(s)
Biosensing Techniques , Nanofibers , Nanoparticles , Carbon Compounds, Inorganic , Electrochemical Techniques , Electrodes , Glucose , Silicon CompoundsABSTRACT
This paper presents an electrospun-nanofibrous-membrane (ENFM) of silicon carbide nanoparticles (SiCNPs) with a conductive polymer (CP) for an electrochemical enzymatic glucose sensor. The surface area of a fiber matrix is a key physical property of a nanofiber membrane for enzyme binding. It is found that glucose sensing electrodes, having a SiCNPs-ENFM nanostructure, show enhanced binding of glucose oxidase (GOx) enzyme within the fibrous membrane. Morphological characterization of SiCNPs based ENFM was performed by using scanning electron microscopy (SEM) and using transmission electron microscopy (TEM) for SiC nanoparticles. The electrochemical analysis of SiCNPs-ENFM electrode was conducted by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) methods. Glucose concentration was detected at +0.6 V in a 5 mM potassium ferricyanide electrolyte. SiCNPs-ENFM based glucose electrodes show a detection range from 0.5 mM to 20 mM concentration with the sensitivity of 30.75 µA/mM cm2 and the detection limit was 0.56 µM. The lower change in current response for SiCNPs-ENFM based glucose sensing electrodes was observed for a 50 day period.