Preparation of hydrophilic molecularly imprinted polymers for tetracycline antibiotics recognition

Hydrophilic molecularly imprinted polymers(MIPs) were prepared using tetracycline as template,methacrylic acid as monomer and glycidilmethacrylate as pro-hydrophilic co-monomer.Compared with common MIPs,the imprinting effect and adsorption amounts of hydrophilic MIPs for tetracycline(TC) were greatly improved in water media.Furthermore,the electrochemical sensor fabricated by modifying hydrophilic MIPs on glassy carbon electrode was developed for the determination of TC in foodstuff samples.     

Europium-sensitized Chemiluminescence of System Tetracycline–H<Subscript>2</Subscript>O<Subscript>2</Subscript>–Fe(II)/(III) and Its Application to the Determination of Tetracycline

Chemiluminescence (CL) of the reaction system tetracycline–H₂O₂–Fe(II)/(III)–Eu(III) was used for the determination of tetracycline hydrochloride in water, pharmaceutical preparations, and honey. The CL spectrum registered for this system shows emission bands typical of Eu(III) ions, with a maximum at λ ∼ 600 nm, corresponding to the electronic transitions of ⁵D₀ → ⁷F₁ and ⁵D₀ → ⁷F₂. A strong chemiluminescence intensity characteristic of europium(III) ions in the system tetracycline–H₂O₂–Fe(II)/(III)–Eu(III), as contrasted to the emission of the system tetracycline–H₂O₂–Fe(II)/(III) without Eu(III), proves that the Eu(III) ion plays the role of a chemiluminescence sensitizer, accompanying tetracycline oxidation in the Fenton system (H₂O₂–Fe(II)/(III)). A linear dependence was observed for the integrated CL light intensity on the tetracycline concentration in the range of 2 × 10⁻⁷ to 3 × 10⁻⁵ mol l⁻¹ with the detection limit of 5 × 10⁻⁸ mol l⁻¹ in aqueous solution.     

原位制备SrSb2O6/g-C3N4新型二维异质结用于可见光催化降解四环素的研究

本文采用高温固相原位制备新型二维SrSb_2O_6/g-C_3N_4异质结光催化复合材料,并将其用于可见光催化降解四环素。通过XRD和FT-IR谱对其结构进行表征。光催化降解实验表明,异质结复合材料较母体g-C_3N_4和SrSb_2O_6而言,光催化效率均得到了提升。其中,异质结样品SSO-CN-2对四环素溶液具有最优的光催化降解效率,其降解率在240min达到62%,分别是母体g-C_3N_4和SrSb_2O_6的2.5和46.0倍。光催化动力学实验表明,其降解曲线符合准一级动力学模型,速率常数为3.920×10~(-3)min~(-1)。循环实验表明,异质结样品的光催化降解性能表现稳定并且结构稳定性较高。活性自由基捕获实验表明,·O~-_2是主要催化反应的活性物种,光催化机理可用半导体异质结Type-II类型得到解释。     

Seaweed-Derived Hierarchically Porous Carbon for Highly Efficient Removal of Tetracycline

Herein we present a facile approach for the preparation of a novel hierarchically porous carbon, in which seaweeds serve as carbon source and KOH as activator. The fabricated KOH-activated seaweed carbon (K-SC) displays strong affinity towards tetracycline with maximum uptake quantity of 853.3 mg/g, significantly higher than other tetracycline adsorbents. The superior adsorption capacity ascribes to large specific surface area (2614 m\begin{document}$ ^2 $\end{document}/g) and hierarchically porous structure of K-SC, along with strong \begin{document}$ \pi $\end{document}-\begin{document}$ \pi $\end{document} interactions between tetracycline and K-SC. In addition, the as-prepared K-SC exhibits fast adsorption kinetics, capable of removing 99% of tetracycline in 30 min. Meanwhile, the exhausted K-SC can be regenerated for four cycling adsorption without an obvious degradation in capacities. More importantly, pH and ionic strengths barely affect the adsorption performance of K-SC, implying electrostatic interactions hardly play any role in tetracycline adsorption process. Furthermore, the K-SC packed fixed-bed column (0.1 g of adsorbents) can continually treat 2780 mL solution spiked with 5.0 mg/g tetracycline before reaching the breakthrough point. All in all, the fabricated K-SC equips with high adsorption capacity, fast adsorption rate, glorious anti-interference capability and good reusability, which make it hold great feasibilities for treating tetracycline contamination in real applications.