一种新型有机磷液晶传感器

A new type of organophosphorus liquid crystal sensor

提出了一种新型有机磷液晶传感器,其基底表面仅由Cu2+功能化。将液晶5CB滴凃其上,利用正交偏光显微镜对传感器的光学表征进行观察。传感器的光学表征随时间逐渐从亮转为暗,且其转为全暗态所需的时间与Cu2+的浓度呈反比;当通入甲基磷酸二甲脂(DMMP)气体时,传感器呈现出逐渐从暗到亮的光学表征变化,循环通入空气和DMMP气体时交替出现的暗与亮的光学表征转变显示了其对DMMP的光学响应具有可重复性;另外,水、乙醇、甲苯和丙酮等其他干扰气体的通入则不会引起光学表征的任何变化。同时,在实验范围内(0.1~10mmol/L),Cu2+的浓度越低,传感器对DMMP的光学响应灵敏度越高。结果表明了这种新型有机磷液晶传感器造价低廉,制作过程简易,可选择性、可重复性地应用于如DMMP等有机磷的检测中。

A new type of organophosphorus liquid crystal sensor is proposed. Surface of substrate is functionalized only with Cu2 ＋. Deposit liquid crystal 5CB on substrate, optical appearance of sensor is observed by a orthometrie polarized microscope. Optical appearance of sensor gradually change from bright to dark with time, and the needed time for realizing full dark increases with the decreasing concentration of Cu2＋ ; when exposing the sensor to DMMP vapor,optical appearance changes from dark to bright. And the optical response is proved to be reversible by the alternately darkening and brightening progress when circularly exposing to air and DMMP vapor. However, no optical change can be observed at other compounds like water, ethanol, acetone and toluene. At the same time, at experimental range of Cu2＋ concentrations （0.1-10 mmol/L） , the lower the Cu2＋ concentration is, the higher the response ~en^itivity is. The results reveal that this new fabrication is low-cost and simple, and the liquid crystal sensor can be used in selectively and reversely detecting organophosphorus such as DMMP.