Department of Chemistry, Himachal Pradesh University, Shimla 171005, India.
J Hazard Mater. 2010 May 15;177(1-3):290-9. doi: 10.1016/j.jhazmat.2009.12.031. Epub 2009 Dec 29.
In order to minimize the agro-environmental pollution and health hazards caused by pesticides, in the present study, the neem leaf powder "(NLP)", a bio-pesticide, has been exploited to develop the pesticide delivery devices. The presence of neem in the formulations along with the pesticide may enhance the potential of these systems due to its inherent pesticidal activity. We have prepared the NLP and alginate based beads by using CaCl(2) as crosslinker. To study the effect of composition of the beads on the release dynamics of fungicide (thiram), beads were prepared by varying the amount of NLP and crosslinker. The beads formed were characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), energy dispersion analysis by X-rays (EDAX), thermogravimetric analysis and swelling study. Formulation characteristics such as entrapment efficiency, bead size, percentage equilibrium swelling of the beads and diffusion mechanism for thiram release have been evaluated. Maximum (78.33+/-2.89)% swelling has occurred in the beads prepared with 1.5% NLP, 2.5% alginate and 0.1M crosslinker solution. In most of the formulations the values for the diffusion exponent 'n' have been obtained >1 and hence the release of fungicides occurred through Case II diffusion mechanism.
为了将农药对农业环境和健康带来的危害降到最低，本研究利用生物农药印楝叶粉（NLP）开发了农药输送装置。由于其固有的杀虫活性，制剂中添加印楝可能会增强这些系统的潜力。我们使用 CaCl2作为交联剂，制备了 NLP 和藻酸盐基珠粒。为了研究珠粒组成对杀菌剂（福美双）释放动力学的影响，我们通过改变 NLP 和交联剂的用量来制备珠粒。通过傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）、X 射线能谱分析（EDAX）、热重分析和溶胀研究对形成的珠粒进行了表征。对包封效率、珠粒大小、珠粒的平衡溶胀百分比和福美双释放的扩散机制等配方特性进行了评估。在 NLP 含量为 1.5%、藻酸盐含量为 2.5%和 0.1M 交联剂溶液制备的珠粒中，出现了最大（78.33+/-2.89）%的溶胀。在大多数制剂中，扩散指数“n”的值均>1，因此杀菌剂通过 II 型扩散机制释放。
