Applications of Surface Modified Ionic Liquid/Nanomaterial Composite in Electrochemical Sensors and Biosensors

Abstract

Nanotechnology is playing an important role in the development of biosensors. The exclusive physical and chemical properties of nanomaterials make them exceptionally suitable for designing new and improved sensing devices, especially electrochemical sensors and biosensors. Room temperature ionic liquids (RTILs) are salts that exist in the liquid phase at and around 298 K and are entirely composed of ions: a bulky, asymmetric organic cation and usually an inorganic anion but some ILs also has organic anion. ILs have received much attention as a replacement for traditional volatile organic solvents as they possess many attractive properties such as intrinsic ion conductivity, low volatility, high chemical and thermal stability, low combustibility, and wide electrochemical windows, etc. Due to negligible or nonzero volatility of these solvents, they are considered “greener” for the environment in comparison to volatile organic compounds. ILs have been widely used in electrodeposition, electrosynthesis, electrocatalysis, electrochemical capacitor, lubricants, plasticizers, solvent, lithium batteries, solvents to manufacture nanomaterials, extraction, gas absorption agents etc. [1, 2, 3, 4]. This review discusses the electrochemical sensors and biosensors based on carbon nanotubes, metal oxide nanoparticles, and ionic liquid/composite modified electrodes. The main thrust of the review is to present an overview on the advantages of use of RTILs along with nanomaterials for electrochemical sensors and biosensors. Consequently, recent developments and major strategies for enhancing sensing performance have been thoroughly discussed.