Shuang Gao,Jingyu Jiang,Xiaoming Li,Yanyan Liu,Lixia Zhao,Ying Fu,Fei Ye
Cyanazine is usually dissolved in organic reagents during use due to the poor solubility in water. However, cyanazine residues in the environment may cause serious harm to the soil, water and human body, etc. In this study, clathrate of cyanazine-beta-cyclodextrin (cyanazine- β -CD) clathrate was synthesized via co-precipitation to enhance the water solubility, thermostability and herbicidal activity of cyanazine. Moreover, the X-ray diffraction, scanning electron microscope and Fourier transform infrared spectroscopy techniques were used to examine the clathrate. Results proved that cyanazine successfully entered the cyclodextrin cavity. Clathrate of cyanazine and β -CD was synthesized in a 1:1 stoichiometric ratio explored using the study of inclusion ratios. Besides, clathrate improved the water solubility of cyanazine, which was proved by the phase solubility study. The improvement of thermal stability was confirmed by thermogravimetric analysis. Furthermore, the biological activity studies indicated the clathrate had better herbicidal activity than cyanazine.
A pipette-tip solid-phase extraction (PT–SPE) method using a sol–gel hybrid adsorbent has been developed. The method could be used for rapid screening of vegetable matrices for cyanazine and atrazine; assay of cucumbers is reported as an example. The sol–gel hybrid adsorbent was synthesized from tetraethyl orthosilicate (TEOS) as the precursor and γ-(methacryloyloxy)propyltrimethoxysilane (KH570) as both surface modifying agent and monomer for the polymerization. Under the optimized conditions, good calibration linearity was obtained in the range 0.022–1.65 μg g −1 with correlation coefficients ( r ) ≥0.9996. Recovery at three spike levels ranged from 87.6 to 93.8 % with relative standard deviations ≤7.8 %. This extraction strategy has several advantages, for example ease of assembly, low cost, and high extraction efficiency, and is a potential pretreatment strategy for rapid screening of cyanazine and atrazine in vegetables.
PT–SPE procedure and chromatograms obtained from cucumber
Shuang Gao,Chao Bie,Qiuyu Ji,Haiyang Ling,Chunyan Li,Ying Fu,Lixia Zhao,Fei Ye
Due to its poor water solubility, the herbicide cyanazine is usually dissolved in organic reagents when used, which poses a great threat to the environment. Poor water solubility also causes limited herbicidal activity. In our study, the water solubility of cyanazine was increased by forming a cyanazine/hydroxypropyl beta-cyclodextrin (HPβCD) inclusion complex. The formation of the inclusion complex was confirmed by FT-IR, XRD, SEM and other characterization methods. Phase solubility study showed that HPβCD could improve the water solubility of cyanazine. Thermogravimetric analysis indicated that the thermal stability of cyanazine was improved by forming inclusion complex and the biological activity test showed that better herbicidal activity was obtained on the inclusion complex compared with the cyanazine. The results showed that the formation of inclusion complex could improve the application of cyanazine in agricultural production and reduce the risk to the environment.
危险品化学品经营许可证（带存储）