Flores-Céspedes Francisco, Villafranca-Sánchez Matilde, Fernández-Pérez Manuel
Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Agrifood Campus of International Excellence (ceiA3), Crta. Sacramento s/n, 04120 Almería, Spain.
Gels. 2023 May 6;9(5):388. doi: 10.3390/gels9050388.
Dodecyl acetate (DDA), a volatile compound present in insect sex pheromones, was incorporated into alginate-based granules to obtain controlled-release formulations (CRFs). In this research, not only was the effect of adding bentonite to the basic alginate-hydrogel formulation studied, but also that of the encapsulation efficiency on the release rate of DDA in laboratory and field experiments. DDA encapsulation efficiency increased as the alginate/bentonite ratio increased. From the preliminary volatilization experiments, a linear relationship was found between the DDA release percentage and the amount of bentonite present in the alginate CRFs. Laboratory kinetic volatilization experiments showed that the selected alginate-bentonite formulation (DDABA) exhibited a prolonged DDA release profile. The value of the diffusional exponent obtained from the Ritger and Peppas model ( = 0.818) indicated that the release process follows a non-Fickian or anomalous transport mechanism. Field volatilization experiments showed a steady release of DDA over time from the alginate-based hydrogels tested. This result, together with those obtained from the laboratory release experiments, allowed the obtainment of a set of parameters to improve the preparation of alginate-based CRFs for the use of volatile biological molecules, such as DDA, in agricultural biological control programs.
十二烷基乙酸酯（DDA）是昆虫性信息素中的一种挥发性化合物，被纳入基于海藻酸盐的颗粒中以获得控释制剂（CRF）。在本研究中，不仅研究了在基本的海藻酸盐水凝胶配方中添加膨润土的效果，还研究了在实验室和田间试验中包封效率对DDA释放速率的影响。随着海藻酸盐/膨润土比例的增加，DDA包封效率提高。从初步挥发实验中发现，DDA释放百分比与海藻酸盐CRF中膨润土的含量之间存在线性关系。实验室动力学挥发实验表明，所选的海藻酸盐 - 膨润土配方（DDABA）呈现出延长的DDA释放曲线。从Ritger和Peppas模型获得的扩散指数值（n = 0.818）表明释放过程遵循非菲克或反常传输机制。田间挥发实验表明，随着时间的推移，所测试的基于海藻酸盐的水凝胶中DDA稳定释放。这一结果与从实验室释放实验中获得的结果一起，使得能够获得一组参数，以改进用于农业生物防治计划中挥发性生物分子（如DDA）的基于海藻酸盐的CRF的制备。
