Fabrication of iron oxide@MOF-808 as a sorbent for magnetic solid phase extraction of benzoylurea insecticides in tea beverages and juice samples.

A novel magnetic metal organic framework composite (Fe3O4@MOF-808) was synthesized by a facile solvothermal method and applied as an adsorbent for the magnetic solid phase extraction (MSPE) of benzoylurea insecticides (BUs) from tea beverages and juice samples. The prepared materials were characterized using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), vibrating sample magnetometry measurements and N2 adsorption-desorption experiments. The adsorption (adsorbent amount, extraction time and pH) and elution (elution solvent, elution volume and time) parameters were investigated in detail. Under the optimized experimental conditions, Fe3O4@MOF-808 exhibited simpler and better reusability than commercial C18, with an equivalent adsorption effect. Notably, π-π interactions, hydrophobic interactions and hydrogen bonding interactions contributed to the good adsorption of BUs by Fe3O4@MOF-808. Finally, a simple and sensitive method was established using Fe3O4@MOF-808-based MSPE coupled with high-performance liquid chromatography (HPLC). It provided low limits of detection (0.04-0.15 ng/mL), wide linear ranges (0.15-50 ng/mL) and satisfactory recoveries (84.6-98.3%). The proposed method was successfully applied for the fast and sensitive determination of BUs in tea beverages and juice samples.

Lead selenide nanoparticles-induced oxidative damage of kidney in rats.

OBJECTIVE: To investigate the effect of lead selenide nanoparticles (nano PbSe) on kidney in rats. METHOD: Specific pathogen free SD rats were randomly divided into 4 groups (8 rats/group), and injected with of 0mg/kg (control group), 10mg/kg (low dose group), 20mg/kg (middle dose group), or 30mg/kg (high dose group) nano PbSe respectively. Seven weeks after injection, the serum was taken from rats for the detection of blood urea nitrogen (BUN), creatinine (Cr) and uric acid (UA). Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) levels were detected using renal tissue homogenate. Pathological examination was performed on kidney sections. RESULTS: The levels of BUN and Cr in three exposure groups were significantly increased compared with those of control group. Levels of UA in middle dose and high dose group were higher than those in the control group. Levels of SOD, GSH-Px and T-AOC in three exposure groups were markedly decreased compared with those in the control group. Levels of MDA in three exposure groups were higher than those in the control group. Pathological changes at different levels of kidneys were observed, and the damage was more serious with the increase of concentration. CONCLUSIONS: Nano PbSe can lead to oxidative damage to the kidney, with the toxicity positively correlates to the dosage.