Anisa Nur Fitrianingrum, Sari Edi Cahyaningrum, Retno Ariadi Lusiana, Endang Tri Wahyuni, Taufik Abdillah Natsir
Fertilizers, especially urea, are essential in enhancing agricultural productivity by providing the nutrients required for optimal plant growth. While urea fertilizer effectively boosts agricultural yield, it can degrade the quality of fertile soils over time. To address this issue, researchers are working on developing controlled-release or slow-release fertilizers. This study aims to produce a multilayer chitosan (CS) modified membrane using citric acid (St) and urea (Ur) as crosslinkers, with a calcium (Ca) ion coating. The composite membrane was prepared and applied as biodegradable SRFs. Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and Differential Scanning Calorimetry (DSC) were used to characterize the composite membrane. The physical properties of the CS/St-Ur/Ca were investigated via swelling, water contact angle, and tensile strength tests. Results showed that incorporating Ca ions into the coating increases the tensile strength and water resistance of the composite membrane. The CS/St-Ur/Ca membranes exhibited controlled nutrient release behavior with a release rate of 0.31 – 0.54% day–1. Preliminary plant growth observations indicated that selected membrane formulations supported vegetative growth. However, performance varied depending on coating density and nutrient release rate, with 50.00% increase in the number of leaves and 70.11% in leaf length compared to control plants without composite membrane treatment. These results suggest that the CS/St-Ur/Ca membrane may provide a promising biodegradable platform for controlled nutrient delivery. However, further optimization is necessary to balance nutrient retention and agronomic performance. © 2026 The Authors
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Yogyakarta, Sekip Utara, 55281, Indonesia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Surabaya, Jl. Ketintang, Gayungan, East Java, Surabaya, 60231, Indonesia; Department of Chemistry, Faculty of Science and Mathematics, Diponegoro University, Jl. Jl. Prof. Soedarto, Tembalang, Central Java, Semarang, 50275, Indonesia
