Synthesis of Electrochemical Biosensor for Detection of Phosphate in Saliva

Abstract

Calcium phosphate is one of the abundant restoratives and bioactive materials which helps in the restoration of bones and early carious lesions. These re-mineralizing resins are mainly composed in the form of calcium orthophosphate. It is the challenge and need of the day to cure the disease by keeping the amount of calcium phosphate, fluoride, and pH of saliva constant means moderate. Now it is the need of the day to make it possible of performing different medical tests results and cure on the spot in this busy era. For this purpose, an electrochemical biosensor method was introduced. This method is robust, accurate, selective, and sensitive for phosphate detection. The combined effect of metal oxide/graphene oxide nanocomposites has attracted a lot of attention. Iron oxide nanoparticles and their composite have several properties that make them interesting for device applications including catalytic activity, high surface area, electrochemical activity, and oxygen transferability. In this work, doped iron oxide/graphene oxide and iron oxide /reduce graphene oxide nanocomposites have been synthesized by hydrothermal and co-precipitation methods. The synthesized materials Fe2O3/GO and Fe2O3/rGO were characterized by (FTIR, XRD, SEM, EDX, and Raman spectroscopy. The electrochemical analytical techniques (cyclic voltammetry, amperometry, and electrochemical impedance spectroscopy) were used for the evaluation of electrochemical sensing properties. The glassy carbon electrode (GCE) surfaces were modified with the synthesized materials (Fe2O3/GO and Fe2O3/rGO ) and tested as an electrochemical sensor for phosphate detection. The proposed sensors Fe2O3/GO/GCE and Fe2O3/rGO/GCE gave excellent results for the detection of phosphate. The Fe2O3/rGO/GCE sensor gave better results as compared to Fe2O3/rGO/GCE because the rGO is highly conductive as compared to the GO. The sensor did not show any interference from the co-existing species (uric acid, glucose, and H2O2 ). The fabricated sensor successfully detected phosphate.