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.

The binary mixtures of Brij® surfactant and Pluronic® F127 were studied as carriers of griseofulvin. The F127 systems and Brij® 78 (C18H37E20), Brij® 98 (C18H35E20) and Brij® 700 (C18H37E100) were prepared in the proportions 10/90, 30/70, 50/50 and 70/30, respectively. The characterizations were carried out by tube inversion, rheology, particle size, and theoretical cmcs. The griseofulvin solubilization tests were performed at 25 and 37 ºC in micellar solutions of 1 wt. % and quantified by UV/Vis. According to the rheological data, the presence of F127 make the F127/Brij 78 70/30 and F127/Brij 98 70/30 mixtures thermoresponsive at concentrations of 30 and 35 wt.%, with transition fluid/gel in the range of 28-30 ºC, ideal for topical use. All of the F127 / Brij 700 mixtures showed moderate distribution polydisperse (PDI < 0.4), as well as mixtures of F127 / Brij 98, with the exception of the mixture with ratio 30/70. Mixtures of F127 / Brij 78 had wide polydisperse distribution (PDI > 0.4). The optimal mixing for oral application would be of F127/Brij 78 because it exhibits greater solubilizing capacity (Scp) of griseofulvin at temperatures of 25 to 37 ºC when compared to F127 alone.

The surfactants were synthesized by condensing the obtained oligosaccharides of amylose and alkyl phenols extracted from the natural cashew nut shell liquid (nCNSL). The Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR) data showed aromatic ring bands, glycosidic rings, olefins and paraffins. The Nuclear Overhauser Effect Spectroscopy (NOESY) experiments showed that the conformation of the glycosidic units is of the type 4C1 with an α anomeric configuration. The values of Gibbs free energy of micellization (ΔGºmic) indicate that the spontaneity of formed micelles are cardanyl oligoglycosides > cardyl oligoglycosides > anacardyl oligoglycosides. The surface tension (γ) measurements showed that critical micelle concentration (cmc) values were low for surfactants. The study γ versus lnc (g dm-3) indicated that the aggregation behavior of the surfactants is dependent on their structural characteristics, as well as their thermal behavior. The area per molecule (A) values indicates that cardyl oligoglycosides are likely to form aggregates smaller than cardanyl oligoglycosides and anacardyl oligoglycosides. The critical packing parameter (cpp) indicates that the aggregates are of the vesicles and bilayers.

The non-commercial copolymers E45S8, E45S17 and their mixtures with Pluronic® P123 (E21P67E21) were studied as carriers of the model drug griseofulvin. Critical micelle concentration (cmc) (dye solubilisation method), drug solubilisation capacity (Scp and Sh) determined by ultraviolet-visible (UV-Vis) spectroscopy and 1H nuclear magnetic resonance (1H NMR) and cytotoxicity (LDH activity in human neutrophils) were studied. E45S17 1.0 wt.% dispersions presented colloidal aggregates limiting its Scp in comparison to E45S8, but in 0.1 wt.% solutions this phenomenon seemed to be absent and E45S17 presented a higher Scp. The mixtures that showed the best Scp results contained 50% of P123 and presented low cmc. An evaluation of literature data suggested a minimum Em content of 62% in EmSn copolymers below which the increase of Sn length does not lead to an increase of Sh. The results suggested no toxicity of the copolymers on human neutrophils, supporting the use of P123 and poly(styrene oxide) containing copolymers as drug carriers.

Cashew nut shell liquid (CNSL) is a by-product of the cashew kernel industry, applied mainly to produce polymeric derivatives. The technical CNSL (CNSLT) was obtained industrially, extracted by roasting the cashew nut shells at temperatures between 180 and 200 ºC. Two methods were used to produce natural CNSL. For the extraction of CNSLNP, the cashew nut shells were pressed at room temperature. CNSLNS was extracted in hexane at room temperature and recovered at 50 ºC. A comparison was made of the composition determined by HPLC and properties generated by viscosity measurements and also by TG, DSC and IPDT (integral procedural decomposition temperature). Natural CNSLs displayed higher content of cardol and anacardic acid and lower percentage of cardanol than CNSLT. The higher content of cardanol in CNSLNS was the major difference between natural CNSLs. CNSLNP had higher levels of impurity, higher viscosity, lower thermoxidative stabilities and lower ebullition temperature. The CNSL obtained by cold solvent extraction and recovery at 50 ºC better preserves the original properties of the liquid.