The Role of Thermotropic Liquid Crystals in the Detection of Gases that Adversely Affect the Nervous System

In this study, the aim was to develop an innovative and user-friendly sensor capable of quickly detecting the gases phenol, toluene, and 1,2-dichloropropane, which negatively affect brain functions when inhaled over extended periods. To achieve this, the thermotropic phase of liquid crystals, which possess thermotropic and lyotropic phases, was used, and a thermotropic cholesteric liquid crystal(CHLC) sample was formulized. The changes occurring in the presence of these gases were examined optically. In this context, the thermotropic ChLC sample, composed of E7 thermotropic liquid crystal and a chiral mixture made from chiral dopants CB15, R1011, and R811, was placed into a cell created using the sandwich method with glass surfaces modified with lecithin. The mentioned gases, evaporated at different temperatures, were introduced into the cells containing the liquid crystal sample over varying durations, and the resulting changes in the wavelength of the liquid crystal were analyzed. Thus, it was demonstrated that these gases, which have a detrimental impact on human health, can be detected at the lowest concentration levels using a sensor containing thermotropic liquid crystal.