Investigation of slow release of urea from biodegradable single- and double-layered hollow nanofibre yarns

Abstract

Urea is the most common form of nitrogenous fertiliser. Recently, research has focused on the development of delivery systems to prolong fertiliser release and prevent fertiliser loss through leaching and volatilization. This study investigates and compares single- and double-layered hollow nanofibrous yarns as novel delivery systems to encapsulate and release urea. Single-layered hollow poly l-lactic acid (PLLA) nanofibre yarns loaded with urea fertiliser were fabricated using a customized electrospinning. Double-layered hollow nanofibre yarns were produced by electrospinning polyhydroxybutyrate (PHB) nanofibres as an outer layer, with urea-impregnated PLLA nanofibres as the inner layer. Scanning electron microscopy (SEM) with an energy-dispersive spectroscopy (EDS) was used to characterize the morphology of hollow electrospun nanofibre yarns. A total nitrogen instrument (TNM-1) was used to study the urea release from single- and double-layered hollow nanofibres yarn in water. A Carbon:Nitrogen (CN) elemental analyser determined encapsulated nitrogen in PLLA nanofibres samples. Results indicated that urea-impregnated double-layered hollow nanofibre yarns significantly started nitrogen releasing at much lower amount during first 12 h compared to single-layered hollow nanofibre yarns (P value = 0.000). In conclusion, double-layered hollow nanofibre yarn has potential as an effective alternative to current methods for the slow release of fertilisers and other plant-required chemicals.

Study on developing a multi-integrated textile system: investigating the liquid loading and release performances of hollow fiber yarns

“…A delivery system to encapsulate and release urea in the form of layered hollow nanofibrous yarns was investigated for the slow release of plant-needed chemicals and fertilizers. 14 This has led to a new inspiration to develop a novel hollow fiber-based agrotextile system with a wide range of potential agricultural applications, such as the slow release of fertilizers, pesticides or other target liquid materials for pest prevention and crop protection. With the potential function of long-lasting release, the effectiveness of the above applications is believed to be maintained even if the amount of agrochemicals is reduced.…”