Liquid Crystal Based Sensors for the Detection of Heavy Metals

Abstract

Arsenic related toxicity contributes heavily to the disease burden globally, resulting in a dire need to discover new and more sensitive means of both; detecting and measuring it. Subsequently, integrating the concepts of nanotechnology and liquid crystalline materials, a new breed of sensors is being suggested. Herein, based on the already reported adsorption affinity cobalt ferrite nanoparticles display for arsenate, the perturbation sensitive and optically anisotropic liquid crystals (LCs) were suggested as a means of detection, transducing and amplifying the said interaction. To test this hypothesis, cobalt ferrite nanoparticles were foremost synthesized and characterized using XRD and SEM. This was followed by establishing optimal concentrations of surfactant and nanoparticles in order to achieve stabilized LC sensing platform. Finally, upon testing varying concentrations of sodium arsenate (1000ppm, 500ppm, 100ppm, 1ppm), optically distinguishable results were observed when viewed under polarized optical microscope, suggesting this sensing platform to exhibit the feature of sensitivity for varying range of arsenate.