Controlled Release of La³⁺ Ions for Enhanced Wheat Seed Germination Based on Phosphate Pillar[5]arene Nanogating

Rare earth elements (REEs), vital and limited resources, also play a significant role in agriculture. Previous findings indicated that the proper concentration of REEs could enhance the germination process, seed germination rate, and seedling growth and development. This paper introduces designing, synthesizing, and assembling a new type of tapered nanogates for separating and detecting lanthanide ions (La³⁺). A phosphoric acid pillar[5]arene (PP5) was synthesized and incorporated as a receptor molecule for La³⁺ in aqueous media. Incorporating these receptor molecules into the nanogates enhances the identification and controlled release of the lanthanide ions in water. The UV titration and COMSOL simulation results demonstrated an interaction between PP5 and La³⁺ to strengthen the understanding of the release mechanism. Finally, the effect of released La³⁺ on the germination of wheat seeds is discussed, demonstrating the ability to improve its application in the agricultural industry.