Liquid Crystal-Based Biosensor to Detect Plant Pathogen

This work demonstrates the specific sensing of plant-pathogen by using a nematic liquid crystal (NLC) material. Nowadays, plant-pathogen is the main component for lowering crop production, hence its detection is a major concern in food safety and quality purposes. The recent developments of liquid crystal (LC) materials have been remarkable in the application of advanced LC biosensors. The director alignment is so sensitive at the interface hence the binding event is amplified in the presence of this LC material which can be easily observed through dielectric and electro-optical spectroscopy. Here, we design a LC-based biosensor for the detection of biological hazards in food and agricultural sectors which directly affect the lifestyle of a human being. Plant infections are caused by different pathogenic microorganisms such as fungi, bacteria, viruses and nematodes. Nematodes are the plant-parasitic roundworms, microscopic, free-living in soil or water and create severe infection in plants and animals. This work illustrates the role of LC for sensing Root-knot nematodes (Meloidogyne species) affected disease in cowpea (Vigna unguiculata) plant and the sensing occurs due to realignment in LC material. This analysis was done through electro-optical measurements and dielectric spectroscopic techniques. Thus, there are several applications of LCs which offer an easy way to fabricate portable biosensors apart from their display applications. This type of sensor provides the fastest response and increases the sensitivity for advancement in diagnostics of various severe diseases.