Photostabilization of Phenoxyacetic Acid Herbicides MCPA and Mecoprop by Hydroxypropyl-beta-cyclodextrin

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Catia Costa (Author) Other; Silvia Maia (Author) Other; Paulo Silva (Author) Other; Jorge Garrido (Author) Other; Fernanda Borges (Author) FCUP; Manuela M Garrido (Author) Other

Journal

Title: International Journal of Photoenergy

Vol. 2013

ISSN: 1110-662X

Publisher: Hindawi

Indexing

ISI Web of Knowledge - 12 Citations

Scopus - 13 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

CORDIS: Physical sciences > Chemistry > Applied chemistry

Other information

Authenticus ID: P-006-FNK

Abstract (EN): New strategies to reduce the environmental and economic costs of pesticides use are currently under study. Microencapsulation has been used as a versatile tool for the production of controlled release agricultural formulations. In this study, the photochemical degradation of the herbicides MCPA and mecoprop has been investigated in different aqueous media such as ultrapure and river water under simulated solar irradiation. To explore the possibility of introducing cyclodextrins in the herbicide formulations, the photodegradation study of the inclusion complexes of MCPA and mecoprop with (2-hydroxypropyl)-beta-cyclodextrin (HP-beta-CD) was also performed. The half-lives of MCPA and mecoprop inclusion complexes were increased approximately by a factor of three related to the free molecules. Additionally, it has been shown that the photodegradation of MCPA and mecoprop is influenced by their structural features. The additional methyl group existing in mecoprop molecular structure has a positive influence on the stabilization of the radical intermediate formed in the first stage of photodegradation of both herbicides. The results found indicated that MCPA and mecoprop form inclusion complexes with HP-beta-CD showing higher photostability compared to free herbicides indicating that HP-beta-CD may serve as ingredient in these herbicide formulations.

Language: English

Type (Professor's evaluation): Scientific