Preventing the release of copper chlorophyllin from crop spray deposits on hydrophobic surfaces

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:582

Article

Wang, Fengyan¹  Ckurshumova, Wenzi²  Liu, Jun²  Fefer, Michael²  Pelton, Robert H.¹ 

[1] McMaster Univ, Dept Chem Engn, 1280 Main St West, Hamilton, ON L8S 4L7, Canada

[2] Suncor AgroSci, 2489 North Sheridan Way, Mississauga, ON L5K 1A8, Canada

关键词: Copper chlorophyllin;    Rainfastness;    Crop spray;    Controlled release;    Polyelectrolyte complex;   

DOI  :  10.1016/j.jcis.2020.09.014

来源: Elsevier

【 摘 要 】

The chlorophyll derivative copper chlorophyllin and related chlorins have promise as environmentally friendly agricultural chemicals, however, spray application is hindered by the propensity of dried spray deposits to wash off leaf surfaces during rain or irrigation. Hypothesis: Polyelectrolyte complexes formed between anionic carboxymethyl cellulose and cationic polyamidoamine-epichlorohydrin can prevent the release of copper chlorophyllin from dried spray deposits on leaf surfaces when exposed to water. Experiments: Sessile drops on parafilm and containing polyelectrolyte complex and copper chlorophyllin or Brilliant Sulfaflavine, an anionic water-soluble dye, were dried to form deposits that were physical models for crop spray drop deposits on hydrophobic leaf surfaces. Larger buffer drops were placed on the dried deposits and the release of copper chlorophyllin or the dye were measured. Findings: Copper chlorophyllin showed some immediate (burst) release upon exposure to buffer whereas the remainder was immobilized on the parafilm. By contrast, Brilliant Sulfaflavine displayed rapid release following square root time dependence, typical of a diffusion-controlled process. The unusual behavior of copper chlorophyllin is attributed to the presence of CuChl nanoparticles when dispersed in water. The nanoparticles are encased in the polyelectrolyte complex that adheres to parafilm. The fraction of the added copper chlorophyllin lost in the burst release can be controlled by varying the polyelectrolyte complex composition and concentration. (C) 2020 The Author(s). Published by Elsevier Inc.

【 授权许可】

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