Multifunctional polyetheramine–epoxide gels and their prospective applications in health and agriculture

In this work, nanogels based on polyetheramine–epoxide (PPO–DPEG) were developed, and two potential envisions for the nanocarriers were explored, for the first time, as controlled drug delivery systems and as stimulants for seed germination in agriculture. These nanogels can help reduce the use of hazardous chemi- cals and expensive instruments, with several advantages: (i) an easy route for their production; (ii) catalyst- free synthesis at low temperature; (iii) water as a unique solvent, which provides advantages in terms of sustainability and cost-effectiveness. First, this study provides a particular drug-polymer design for the sustained release of the antibiotic ciprofloxacin. Second, seed germination assays demonstrated that the nanogels could be used as novel materials to promote the germination and growth (root and shoot) of cucumber seeds. In this sense, the root length of cucumber seeds was improved by 39% compared to the negative control (water). The obtained polymeric gels were in depth characterized by various physicochemical techniques such as dynamic light scattering (DLS) and zeta potential, thermogravimetric analysis (TGA), transmission electron microscopy (TEM), ultra-small angle X-ray scattering (USAXS), and X-ray fluorescence spectroscopy (m-XRF). The cytotoxicity of PPO–DPEG gels was evaluated by XTT assays, con- firming good biocompatibility after exposure to GM07492A cell line (normal human lung fibroblasts). The possibility to use these nanogels for agricultural science is novel, providing good carrier opportunities for embedded micronutrients (and mass production) for the development of an innovative and highly versatile platform for sustainable delivery systems in plants.