STARCH UREA-FORMALDEHYDE MATRIX ENCAPSULATION OF SOLID AGROCHEMICALS .3. STUDIES AND BIOEFFICACY TRIALS ON DOUBLE ENCAPSULATION

A technique for the double encapsulation of carbofuran in starch urea formaldehyde (Starch-UF) matrix has been developed. The solid particles of carbofuran were first microencapsulated with UF resin and these microcapsules were then dispersed in the Starch-UF matrix to obtain a granular formulation. The rate of release of carbofuran from these granules was found to be governed by its diffusion through the solid UF resin shell and was significantly slower than from the single encapsulated granular formulation prepared by dispersing uncoated carbofuran in Starch-UF matrix. The bioefficacy of these double encapsulated granules (Encecap-D 3G), was evaluated for persistence against rice pests in paddy and against subterranean pests in potato, in comparison with conventional formulations of carbofuran, phorate, quinalphos, aldicarb and cadusafos. The persistence of Encecap-D 3G was found to be better than that of the standard formulation in the cultivation of paddy under flooded conditions and in the cultivation of potato. The order of efficacy was found to be: White grubs-Encecap-D 3G > quinalphos > cadusafos > aldicarb > phorate > Furadan 3G; Nematodes-cadusafos > Encecap-D 3G > quinalphos > aldicarb > phorate > 'Furadan' 3G

SLN and NLC for topical, dermal, and transdermal drug delivery

Introduction: From a biopharmaceutical standpoint, the skin is recognized as an interesting route for drug delivery. In general, small molecules are able to penetrate the stratum corneum, the outermost layer of the skin. In contrast, the delivery of larger molecules, such as peptides and proteins, remains a challenge. Nanoparticles have been exploited not only to enhance skin penetration of drugs but also to expand the range of molecules to be clinically used.Areas covered: This review focus on Solid lipid nanoparticles (SLN) and Nanostructured lipid carriers (NLC) for skin administration. We discuss the selection criteria for lipids, surfactants, and surface modifiers commonly in use in SLN/NLC, their production techniques, and the range of drugs loaded in these lipid nanoparticles for the treatment of skin disorders.Expert opinion: Depending on the lipid and surfactant composition, different nanoparticle morphologies can be generated. Both SLN and NLC are composed of lipids that resemble those of the skin and sebum, which contribute to their enhanced biocompatibility, with limited toxicological risk. SLN and NLC can be loaded with very chemically different drugs, may provide a tunable release profile, can be produced in a sterilized environment, and be scaled-up without the need for organic solvents.The authors acknowledge CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for the financial support and for the fellowship of the second author (88887.368385/2019-00). Authors also acknowledge the support received from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER, under the Partnership Agreement PT2020, for the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund).info:eu-repo/semantics/publishedVersio