Study On The Detection Of Tetracyclines By Molecularly Imprinted Photonic Crystal Sensor

Tetracycline antibiotics are widely used as feed additives in livestock and poultry production.However,the detection of such antibiotics is particularly important due to their environmental pollution and the generation of drug-resistant bacteria.In this paper,a series of two-dimensional photonic crystal gel arrays of tetracycline antibiotics were prepared by the method of molecular imprinting and photonic crystal.On the basis of this,the tetracycline antibiotics were analyzed and tested.In this paper,an oxytetracycline imprinted Two-dimensional(2-D)photonic crystal gel array was first prepared and investigated to find that when the oxytetracycline(OTC)concentration increased from 0 to 60 ?M,the lattice spacing increased from 788 nm to882 nm in 20 min,Its structural color also changed from blue to green,then to orange,finally red,and reproducibility was good after three replicates.In contrast,the adsorption capacity of non-imprinted gels array towards oxytetracyclines was low,the particle spacing increased from 790 nm to 820 nm,the structural color has also remained blue.The selectivity of oxytetracycline imprinted gels is also very good.The actual sample of milk after spiked for the detection of oxytetracycline also performed well.2-D gel arrays of tetracycline(TC),chlortetracycline(CTC)and doxycycline(DOC)were then prepared in the same manner,each of which showed a specific response to the imprinting molecules.The structural color Change basically follow the change from blue to green to orange and finally into the red law.This material proved to be universal in the tetracycline system.In addition to the 2-D gels imprinted with tetracycline antibiotics,composite microspheres of ?-estradiol imprinted on the surface of silica were also prepared.The composite imprinted microspheres with a diameter of about 840 nm are arranged into a2-D photonic crystal array.Comparison of test results of ?-estradiol solution by imprinted and non-imprinted arrays revealed that the imprinting effect was significant and the array selectivity of ?-estradiol imprinting was found to be good in comparison with estrone and diethylstilbestrol testing.