Biodegradable floating hydrogel baits as larvicide delivery systems against mosquitoes

• DOI: 10.1039/d2sm00889k
• Publication Date: 2022-08-03T18:01:12Z
• Authors: Marco Piazzoni; Agata Negri; Elisa Brambilla; Laura Giussani; Simone Pitton; Silvia Caccia; Sara Epis; Claudio Bandi; Silvia Locarno; Cristina Lenardi
• Keywords: Larvicide; Delivery system

Biological methods for mosquito larvae control are completely biodegradable and have null or limited effects on nontarget organisms. However, commercially available products a low residual activity, with the consequent need multiple applications that inevitably increase costs risk of resistance phenomena insurgence. Smart delivery systems made hydrogels proved their efficacy in increasing action duration biolarvicides up to several months, but lack an efficient baiting mechanism strongly attract target pest remains problem practical applications. In this work, we investigated two novel hydrogel-based formulations natural composition killing Aedes albopictus mosquitos. The proposed materials consist charged crosslinked polysaccharides (chitosan cellulose) specifically manufactured float water, simulating organic matter usually present at breeding sites. Within hydrogels' matrix, yeast colonies Saccharomyces cerevisiae were embedded as phagostimulants alongside biolarvicide (Bacillus thuringiensis var. israelensis (Bti)). Despite similar chemical nature structure, chitosan-based exhibited markedly superior potential compared those cellulose also succeeded efficiently just after few hours from administration. We confident smart hydrogel chitosan can be enabling tool towards biopesticides different without delocalizing active ingredients away site simultaneously thus holding minimizing environmental pollution related vector-borne disease prevention.