A simple, new aptamer-photonic crystal encoded suspension array was designed to simultaneously quantify and qualify ochratoxin A(OTA) and fumonisin B1(FB1) in cereal samples. The aptamers of OTA and FB1 were immobilized on the surfaces of photonic crystals by chemical bonding. When the target mycotoxins appear in a sample, the fluorescence-labeled complementary DNA of the aptamer dissociates from their double DNA hybrid and results in an obvious decrease in fluorescence intensity of the microsphere. The difference value of fluorescent intensities for each kind of silica photonic crystal microsphere (SPCM) quantitatively conveys the concentration of mycotoxin, and the structure colors or reflectance peak positions of the SPCMs confirm the kind of mycotoxin detected. The reaction conditions including the immobilization method for aptamers, hybridization, and incubation conditions have been optimized. This developed method displayed a wide linear detection range (0.01-1 ng/mL for OTA and 0.001-1 ng/mL for FB1) and a low limit of detection (0.25 pg/mL for OTA and 0.16 pg/mL for FB1). The recovery rates in the spiked cereal samples ranged from 81.80% to 116.38% for OTA and 76.58%-114.79% for FB1. The positive detection results in the naturally contaminated cereal samples were in agreement with those of classic enzyme-linked immunosorbent assay (ELISA). This simple suspension array scheme displays a great application potential for the high throughput screen assay of mycotoxins.

Facile synthesis of Cu2O–Cu nanocomposites by using a low-power CO2 laser was realized, and the fabricated nanomaterials showed excellent photocatalytic activity for the degradation of various dyes.

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A novel carrier delivery system for curcumin based on porous silicon (pSi) has been developed. The pSi film was prepared by electrochemical etching method and the microparticles of pSi were obtained by ultrasonication. The pSi film and particles of pSi were characterized by scanning electron microscopy (SEM). Sodium nitrite can induce curcumin into pSi and improve the drug loading (DL) and encapsulation efficiency (EE) of curcumin in double-distilled water loading buffer solution. Curcumin on the pSi surface was confirmed by Fourier transform infrared spectroscopy (FTIR) and UV-spectroscopy. The optimal loading conditions of curcumin in pSi are investigated. The curcumin in pSi keeps more than 95% bioactivity for 3 h and good repeatability. The cumulative release ratio of curcumin from PSi can reach 35% after 10 h. The in vitro cytotoxicity of curcumin loaded pSi was evaluated with HT-29 and NCM460 cell lines. The pSi delivery carrier can provide a controlled release and efficacy system for curcumin.

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