红外光谱测定β-CD-氯菊酯包合物主-客体比的研究

Study on Measuring Host-Guest Ratio of Inclusion Compound of β-CD-Permethrin by IR

氯菊酯 (P)是目前我国茶园允许使用的拟除虫菊酯仿生农药品种之一 ,有见光易分解的特点 ,将其制成环糊精包合物 (IC) ,可以增加其稳定性 ,从而减少用量、减少在茶叶等作物上残留量。包合比是包合物加工的重要参数之一。作者用饱和水溶液法制备了 β 环糊精 (CD) 氯菊酯包合物 ,并对其进行了红外光谱分析。结果显示主、客体各吸收峰的位置和强度均不因形成包合物而改变。首次用红外内标法测得 β CD 氯菊酯的包合比为 1∶1。所选内标物质为硫氰化钾 ,因为它仅在 2 10 0cm- 1 处有一个强吸收峰 ,以该峰为硫氰化钾的定量峰。以 5 80cm- 1 处 β CD的环振动特征吸收 ,为 β CD的定量峰。将硫氰化钾与 β CD以一定的质量比混合 ,进行红外光谱分析 ,建立内标工作曲线。为超分子主。

Permethrin is one of the agrochemicals used in tea gardens currently with the characteristic of being easily decomposed in light. Permethrin with β cyclodextrin(CD) made into Inclusion Compound (IC) can increase its stability and reduce dosage to remain on the tea. Host/guest ratio is one of the important parameters of IC. The IC of permethrin with β CD was prepared by means of liquid phase method and characterized by using IR. The result of the IR proves that the characteristic absorption peaks of the host and guest are not changed by forming their IC. The host/guest ratio of the IC measured by IR is 1∶1. Potassium sulfocyanate(KSCN) was chosen as an inside mark material, because it has only one strong absorption peak at 2 100 cm -1 and the peak was chosen as a quantitative peak of KSCN. The peak at 580 cm -1 is the characteristic absorption of the wreath vibration of β CD and was chosen as a quantitative peak of β CD. KSCN and β CD were mixed with a certain quantity ratio and the mixture was analyzed by IR. The work curve of IR was established. A kind of new experimental method of measuring host/guest ratio of the IC was provided.