Study On The Preparation And Application Of Chlorosalicylicamide Sustained-release Granules

In this thesis, a novel Chlorosalicylicamide(quinoid-2 ?, 5-dichloro-4 ?-nitrosalicylanilide from niclosamide) sustained release granule molluscicide(LDS-SRM) were synthesized by screening carriers, surfactants, adhesives, defoamers and lubricants. The bulk density, moisture, critical relative humidity, thermal stability and release rate were determined. The main contents include the following three parts:1. Three kinds of analysis methods were established. First, the aqueous solutions of LDS were measured by ultraviolet-visible spectrophotometry directly. The experimental results showed that the average recoveries were in the range of 101.1%-110.1%. Second, the samples were preprocessed with cloud point extraction and determined by UV-vis spectrophotometry : In the conditions of adding 12% Tributyltetradecylphosphonium chloride(TTPC)at pH 3.5, an equilibrium temperature of 30 ?,an equilibrium time of 50 min and sodium chloride sodium concentration of 1.5 mol/L, the average recoveries were in the range of 101.8%—108.4%, and the limit of detection was 0.0479 ?g/mL. Third, the low-concentration aqueous solutions of LDS were measured by high performance liquid chromatography. The results showed that the recoveries were in the range of 96.3%—98.4%. The analysis methods established above can thus basically meet the needs of testing.2. The 5% and 10% LDS-SRM sustained release granules are both red brown and they have good fluidity. The bulk density of 5% and 10% LDS-SRM were 0.655 g/ml and 0.594 g/ml respectively; the moisture content were 1.15% and 1.28%; the angle of repose were respectively 39.8° and 39.7°; the critical relative humidity were 64.98% and 61.63%; the thermal stability were qualified. The release curve showed that both 5% and 10% LDS-SRM released stably from the first to the ninth day, while the release speed of 5% LDS-SRM was faster than 10% LDS-SRM. The burst release was found in the tenth day for 5% LDS-SRM and the fifteenth day for 10% LDS-SRM. After fourteen days and the twenty days, the release speed of both sustained-release granules tended to 100% respectively.3. Using the immersion test in the lab, the snail mortality rates of 5% LDS-SRM for 1.6 mg/L and higher concentrations last 48 h, or 0.1 mg/L and higher concentrations last 72 h, were all 100%. With the spraying test in the lab, the snail mortality rates of 5% LDS-SRM for 1.6?6.4 g/m~2 last 7 d, or 3.2?6.4 g/m~2 last 14 d, were all more than 95%. Using the immersion test in the fields, the snail mortality rates which 1.6 g/m3 last 72 h both of 5% LDS-SRM and 10% LDS-SRM were all more than 95%. Using the spraying test in the fields, the snail mortality rates which 3.2 g/m~2 last 3 d?7 d and 14 d for 5% LDS-SRM and 10% LDS-SRM were all more than 85%, and compared with the snail mortality rates of 50% WPN 1.0 g/m~2,they were higher than WPN. Both 5% and 10% LDS-SRM were used in the immersion test and the spraying test, the results showed that both of the concentrations(or dosages) of LDS-SRM meet the requirements of ?Efficacy test methods and evaluation of molluscicide for pesticide registration?.