Polyimidazolyl acetate ionic liquid grafted on cellulose filter paper as thin-film extraction phase for extraction of non-steroidal anti-inflammatory drugs from water.

Recently, pharmaceuticals and personal care products in the water environment exhibited potential risks to both human and aquatic organisms. In order to improve the sensitivity and accuracy of pharmaceutical detection, the polyimidazolyl acetate ionic liquid was synthesized by Radziszewski reaction and coated on cellulose filter papers as a thin-film extraction phase for extraction of non-steroidal anti-inflammatory drugs from water. The attenuated total reflection-infrared spectrometry, thermogravimetric analysis, and scanning electron microscope analyses demonstrated that the polyimidazolyl acetate ionic liquid was successfully prepared and attached to the surface of the cellulose filter paper through chemical bonding. The adsorption capacity of the homemade thin-film extraction material for the four non-steroidal anti-inflammatory drugs was greater than 8898 ng/cm2 under the optimum conditions, and the desorption rate was over 90%. Then, a paper-based thin-film extraction phase-high-performance liquid chromatography-tandem mass spectrometry method was established for the extraction of non-steroidal anti-inflammatory drugs in water. This method provided limits of detection and limits of quantification were in the range of 0.02-0.15 and 0.17-0.50 µg/L, respectively. Hence, the obtained thin-film extraction phase showed excellent recovery and reproducibility for the target non-steroidal anti-inflammatory drugs with carboxyl groups from water.

Effects of bisbenzylisoquinoline alkaloid tetrandrine derivative HL-27 on biological properties of BLM helicase / 中国药理学通报

Aim To investigate the effects of bisbenzyl-isoquinoline alkaloid tetrandrine derivative HL-27 on the biological properties of the BLM642-1290 helicase. Methods Fluorescence polarization technique was used to investigate the effects of bisbenzylisoquinoline alkaloid tetrandrine derivative HL-27 on the DNA bind-ing activity and unwinding activity of the BLM642-1290 helicase. Malachite green-phosphate ammonium molyb-date colorimetry was used to investigate the effects of HL-27 on the ATPase activity of the BLM642-1290 heli-case. Ultraviolet spectral scanning was used to investi-gate the effects of HL-27 on the conformation of the BLM642-1290 helicase. Results When the concentra-tion of HL-27 reached 33.34 μmol·L-1, the inhibi-tion ratio of dsDNA and ssDNA binding activity of the BLM642-1290 helicase was 41.35% and 59.54% , re-spectively. When the concentration of HL-27 reached 50 μmol·L-1, the inhibition ratio of DNA unwinding activity of the BLM642-1290 helicase was 78.68% . When the concentration of HL-27 reached 100 μmol· L-1, the inhibition ratio of ATPase activity of the BLM642-1290 helicase was 43.8% . Conclusion The DNA binding activity, ATPase activity and unwinding activity of the BLM642-1290 helicase can be inhibited by bisbenzylisoquinoline alkaloid tetrandrine derivative HL-27.

2-(4-Methyl-phen-yl)-5-[({[5-(4-methyl-phen-yl)-1,3,4-thia-diazol-2-yl]sulfan-yl}meth-yl)sulfan-yl]-1,3,4-thia-diazole.

In the title compound, C(19)H(16)N(4)S(4), the mol-ecules exhibit a butterfly conformation, where the thia-diazole and attached benzene rings in two wings are almost coplanar, with dihedral angles of 0.8 (3) and 0.9 (3)°, respectively, while the two thia-diazole rings form a dihedral angle of 46.3 (3)°.

[Monitoring the stoichiometric relation of ammonium oxidation with the titrimetry of hydrogen ion variation].

A set of automatically titrimetric system to monitor the hydrogen ion variation during biological wastewater treatment process in a batch bioreactor was developed, which consists of a batch bioreactor, data auto-acquisition and preservation unit, and titrant autodosing unit. The accuracy of measurement for the system was evaluated by measuring the stoichiometric ratio of hydrogen ion production amount to ammonium consumption amount of ammonium oxidation in an activated sludge system. The ratios measured in a 1L bioreactor with NH4+ -N concentrations of 1.67, 3.33, 8.33, 16. 66 and 30.00 mg/L as N respectively were very close to the theoretical value, and the relative errors were among 2.09%-6.34%. However, the relative errors in bioreactors of 1, 2, 3 and 4 L with NH4+ -N concentration of 16.66 mg/L as N were among 2.09%- -18.57%, and increased significantly with accretion of the volume of bioreactor. The buffers of bicarbonate and the ammonium, especially the titrimetric dynamic effects in a larger bioreactor are the primarily factors resulting in errors. This study provides an important approach for monitoring hydrogen ion variation in the process of biological wastewater treatment by titrimetry.