Study on development of triglyceride biosensor based on Nano Materials

Abstract

A transparent, highly stable, reliable, ERGO thin film is developed on ITO (ERGO/ITO) surface within 60 sec using chronoamperometric technique. The ERGO/ITO surface provides biocompatible microenvironment towards LIP enzyme and is explored to construct LIP/ERGO/ITO surface for utilization as TG bioelectrode. The LIP/ERGO/ITO TG shows exceptional performance for detection of TG with low Kappm value of 0.2 mM, wide linear detection range of 50-300 mg dL-1 and high sensitivity (37 pA mg dLand#8722;1 cmand#8722;2) . But the LIP/ERGO/ITO bioelectrode experiences interference from urea and uric acid. In order to analyze the interference, SPR based biosensors (LIP/GO/4-ATP/Au and LIP/RGO/4-ATP/Au) are constructed using GO and RGO (chemically reduced graphene oxide) modified SPR surfaces. The LIP/GO/4-ATP/Au surface, offers a linear detection range of 20 mg dL-1 to 350 mg dL-1 with a LOD of 20 mg dL-1 for TG analysis. The LIP/RGO/4-ATP/Au SPR surface provides a linear detection range of 0.09 mg dL-1 to 250 mg dL-1 with a LOD of 0.09 mg dL-1 for TG sensing. The LOD of 0.09 mgdL-1 for TG detection is the first time reported to the best of our knowledge. Analysis of (LIP/GO/4-ATP/Au and LIP/RGO/4-ATP/Au) SPR surfaces manifest that LIP strongly participates in non-specific binding with serum substances. Thus, surface plasmon resonance technique could be considered as a routine analysis before developing a novel surface for biochemical sensing adopted for clinical diagnosis to avoid false results. Comparing the characteristics of ERGO and RGO, it is observed that properties of ERGO have near identical features to graphene than RGO. Therefore, a bienzymatic biosensor LIP-GDH/ERGO/ITO have been developed to detect reliably and selectively TG in blood serum and novel biochemical path has been derived to avoid biological mediator NAD+/NADH. The proposed LIP-GDH/TB/ERGO/ITO electrode provides reproducible sensing characteristics with a sensitivity of 25 pA mg dLand#8722;1 cmand#8722;2 at a low detection limit of 25 mg dLand#8722;1 and low response time of 12 sec.