Chamorro Andrés F, Palencia Manuel, Combatt Enrique M
Research Group of Electrochemistry and Environment (GIEMA), Faculty of Basic Sciences, Universidad Santiago de Cali, Cali 760035, Colombia.
Research Group in Science with Technological Applications (GICAT), Department of Chemistry, Faculty of Natural and Exact Science, Universidad del Valle, Cali 760032, Colombia.
Gels. 2024 Jun 28;10(7):431. doi: 10.3390/gels10070431.
Phosphorous (P) is one the most important elements in several biological cycles, and is a fundamental component of soil, plants and living organisms. P has a low mobility and is quickly adsorbed on clayey soils, limiting its availability and absorption by plants. Here, biodegradable hydrogels based on Cassava starch crosslinked with citric acid (CA) were made and loaded with KHPO and phosphorite to promote the slow release of phosphorus, the storing of water, and the reduction in P requirements during fertilization operations. Crosslinking as a function of CA concentrations was investigated by ATR-FTIR and TGA. The water absorption capacity (WAC) and P release, under different humic acid concentration regimens, were studied by in vitro tests. It is concluded that hydrogel formed from 10% / of CA showed the lowest WAC because of a high crosslinking degree. Hydrogel containing 10% / of phosphorite was shown to be useful to encouraging the slow release of P, its release behavior being fitted to the Higuchi kinetics model. In addition, P release increased as humic acid contents were increased. These findings suggest that these hydrogels could be used for encouraging P slow release during crop production.
磷（P）是几种生物循环中最重要的元素之一，是土壤、植物和生物体的基本组成部分。磷的迁移性低，在粘性土壤上很快被吸附，限制了其有效性和被植物吸收的程度。在此，制备了基于木薯淀粉与柠檬酸（CA）交联的可生物降解水凝胶，并负载了磷酸二氢钾和磷矿粉，以促进磷的缓慢释放、水分储存以及减少施肥操作期间的磷需求。通过衰减全反射傅里叶变换红外光谱（ATR-FTIR）和热重分析（TGA）研究了作为CA浓度函数的交联情况。通过体外试验研究了在不同腐殖酸浓度方案下的吸水能力（WAC）和磷释放情况。得出的结论是，由10%的CA形成的水凝胶由于交联度高而显示出最低的WAC。含有10%磷矿粉的水凝胶被证明有助于促进磷的缓慢释放，其释放行为符合 Higuchi动力学模型。此外，随着腐殖酸含量的增加磷释放量增加。这些发现表明，这些水凝胶可用于促进作物生产过程中磷的缓慢释放。
