Toxicity of neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857)

The golden mussel Limnoperna fortunei (Dunker 1857) is one of the most distributed Nuisance Invasive Species (NIS) in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm). Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus) were also made with the aim to evaluate the potential toxicity of the Neem's solution in the environment. The LC100 of Neem's solution obtained for larvae was 500 μl/L, a value much higher than the one obtained for D. magna and C. decemmaculatus. Thus, we recommend that it should not be used in open waters. However, since the adults were killed in 72 h and the larvae in 24 h, this product can be used in closed systems, in man-made facilities.Facultad de Ciencias Naturales y Muse

Dual ionic crosslinked interpenetrating network of alginate-cellulose beads with enhanced mechanical properties for biocompatible encapsulation

Alginate beads have been a popular carrier of a wide array of biologically relevant molecules, such as proteins, genes, and cells, for biomedical applications. However, the difficulty of controlling their mechanical properties as well as maintaining the long-term structural integrity has prevented more widespread utilization. Herein, a simple yet highly efficient method of engineering alginate beads with improved mechanical properties is presented, whereby a secondary network of biocompatible anionic cellulose is created within the alginate network. The aqueous-soluble anionic cellulose, containing either carboxylate or sulfonate, is found to undergo crosslinking reaction with trivalent ions more favorably than divalent ions, necessitating a dual sequential ionic crosslinking scheme to create interpenetrating networks (IPN) of alginate and cellulose with divalent and trivalent ions, respectively. The IPN alginate-cellulose beads demonstrate superior mechanical strength and controllable rigidity as well as enhanced resistance to harsh chemical environment as compared to alginate beads. Furthermore, their suitability for biomedical applications is also demonstrated by encapsulating microbial species to maximize their bioactivity and therapeutic agents for controlled release