Two-dimensional molecularly imprinted photonic crystal sensor for highly efficient tetracycline detection
A two-dimensional (2D) molecularly imprinted photonic crystal (MIPC) sensor for the detection of tetracycline in foods was fabricated. The MIPC were prepared by a thermal polymerization method with polystyrene 2D photonic crystal (2D-PC) as template, tetracycline as template molecule, acrylamide as functional monomer, and ethylene glycol dimethacrylate as crosslinking agent. The detection of the fabricated MIPC to tetracycline (TC) was applied through a visual change of Debye diffraction ring. Typically, the color of the MIPC turned from red to blue with an 11 mm increase in the diameter of Debye ring when the TC concentration increased to 10-6 mol/L. The fabricated sensor exhibited high selectivity for TC with response time less than 10 min compared to similar compounds. The sensor maintained high sensitivity after five recycles with recoveries of TC around 88.4% and 91.0% in pork and milk samples respectively. We envision that the MIPC sensor could be applied for detection of TC in food samples and other complicated systems.