Precisely controlled delivery of plant hormone using poly

• Published in: Polymer engineering and science 2021-08, Vol.61 (8), p.2172
• Main Authors: Viboonratanasri, Duangkamon, Thongdee, Paptawan, Prajuabsuk, Malee, Pungpo, Pornpan, Vayachuta, Lapporn, Prompinit, Panida
• Format: Article
• Language: English
• Subjects: Physiological aspects; Plant hormones; Polyvinyl alcohol; Zeolites
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.25744

Programmable release of a plant hormone, 1-naphthylacetic acid (NAA), could be achieved by using a novel zeolite-hydrofilm (ZHF) composite. The ZHF was prepared using poly(vinyl alcohol) and glutaraldehyde as a cross-linking agent with the addition of different amounts of zeolite A (0, 1.5, 2.0, 2.5, and 3.0 wt%). This reveals that ZHF was formed as a phase-separated microcomposite with chemical interactions between zeolite A and polymer matrix. We found that the composite film with 2.5 wt% zeolite A had the largest pore size, which exhibited the highest water absorbency and the longest water retention time of over 7 h with high thermal and mechanical stabilities. Release profile displayed rapid desorption of NAA from the film at the initial stage, followed by sustained release thereafter. This behavior was explained by the Korsmeyer-Peppas model with a predominant mechanism of simple Fickian diffusion. Additionally, ZHF with NAA could effectively enhance adventitious root formation of Ocimum basilicum Linn, (sweet basil) cuttings due to accurate releasing NAA and time duration for releasing plant hormone. Finally, the NAA released at the film surface could be in a controlled manner with less negative impact on plant and environment.