Anacardic acid (AA) is a bioactive phytochemical found in the nutshell of Anacardium occidentale, a tropical plant originally from Brazil. In this work, cross-linked anacardic acid nanocapsules (NC) were obtained by interfacial polymerization carried out using the inverse miniemulsion technique with 2,4-toluene diisocyanate (TDI). For this purpose, a functionalized monomer from AA was synthesized for formation of lipase-cleavable ester linkages by coupling of amino acids. The synthesis was planned so that when these ester linkages get exposed to an enzyme, they are broken down and released AA. Furthermore, the N-termini of the coupled amino compounds were used as sites for the polyaddition with TDI at the droplet interface in the inverse miniemulsion. The permeability of the shell was studied on the fluorescent dye, sulforhodamine 101 (SR101), using fuorescence spectroscopy After redispersion in water, the enzymatic cleavage of NC and the release of the SR101 were both monitored in real time. The released AA was proven to be active in vitro against Bacillus subtilis colonies in the bacterial tests. The results indicate that the use of NC is a promising strategy, which can make feasible the application of AA for therapeutic purposes and as nanocarriers for the delivery of active components.

Micelles have aroused interest due to their ability to assist in the transport of poorly soluble drugs. In this study the mixture of copolymers F127/E45S8 in different proportions (F/ES 30/70, 50/50 and 70/30) was performed to improve the bioavailability of griseofulvin and quercetin. The results of cytotoxicity (MTT assay) revealed that the copolymers F127 and E45S8 had considerable biocompatibility and did not affect the metabolism of human neutrophils. The binary systems were also evaluated by critical micellar concentration (CMC) and thermoresponsive behavior. The CMC values were intermediate to those of the isolated copolymers. The systems maintained the thermoresponsive properties present in F127 making the systems interesting for subcutaneous administration. The systems presented small size, an average range in size from 17 to 38 nm, and the samples prepared with higher hydrophobic proportion presented more uniform sizes. Results suggest stability and the increasing of the nanosystems circulation time. The F/ES 30/70 system has polydispersity smaller than 0.1 and showed an increase of 129 times for quercetin solubility. Thus, it is possible to consider F127/E45S8 micelles as potential nanosystems for poorly soluble drug delivery.

Alkyl polyglycosides (APGs) are new biodegradable surfactants, non-toxic, synthesized from abundant renewable sources, potentially more appropriate than anionic surfactants. A range of glycosides denoted APG-Cy was synthesized by the Köenig-Knorr reaction using C10, C16 and C18 alcohols and derived from the degradation of amylose from English potato. The molecular structures of the glycosides were characterized by Nuclear Magnetic Resonance (1H and 13C NMR) together with Infrared Spectroscopy (FTIR) and Gel Permeation Chromatography (GPC). The study by NMR allowed the junctions between hydrophilic head groups and hydrophobic tail-groups to be characterized in detail. Conformation of the glycosidic units is 4C1 type with a b anomeric configuration. The formation of glycosides with five glucose rings linked to the alkyl chain was confirmed by 1H NMR and GPC. Liquid crystals identified by the presence of double melting points were observed by Differential Scanning Calorimetry (DSC) showing thermotropic properties. The surface tension (γ) and critical micelle concentration (cmc) were determined by du Noüy method, noting that increasing the length of alkyl chain led to the expected reduction in the cmc. The energies of adsorption and micellization processes calculated from isotherms γ versus ln c (g.dm-3) indicate cooperativeness of hydrophilic and hydrophobic groups.