Sodium Dichloroisocyanurate Molecularly Imprinted 2D Photonic Crystal Hydrogel Sensor

Abstract

Sodium dichloroisocyanurate (SDIC) is an efficient, safe and convenient halogen disinfectant, which is widely used in hospital disinfection, tableware disinfection and swimming pool disinfection. In order to ensure the use effect and safety, especially in clinical use, it is necessary to carry out effective identification. The effective chlorine content is one of the quality standards for chlorine-containing disinfectants, but its complex experimental operation, poor specificity and portability limit its application. In contrast, testing based on molecularly imprinted photonic crystals sensors provide excellent performance. Therefore, it is of great significance to establish a new and simple SDIC recognition method. We prepared a novel molecularly imprinted two-dimensional (2D) photonic crystal hydrogel (MIPH) for sensitive and label-free recognition of SDIC. The response performance of the resultant MIPH sensor was determined by monitoring the particle spacing changes of the polystyrene (PS) 2D photonic crystal embedded in the hydrogel. The particle spacing changes can be acquired by measuring the diameter changes of the Debye diffraction ring of the MIPH sensor. As the concentration of SDIC in solution increased from 1×10-2 to 1.0 mmol/L, the diameter of Debye diffraction ring increased by 6 mm, and the corresponding photonic crystal particle spacing decreased by 56 nm. The particle spacing change of the MIPH sensor was linear to the SCDI concentration in the range of 1×10-2 to 1.0 mmol/L and the limit of detection (S/N=3) was found to be 3×10-3 mmol/L. The constructed hydrogel sensor was successfully used to detect SDIC in sodium dichloroisocyanurate disinfectant powder with recoveries of 96-100% and RSDs of 7.2-7.6%. Our molecularly imprinted SDIC photonic crystal hydrogels provide a universal strategy for designing other clinical disinfectants sensors.