pH-controlled breakup of fractal aggregates, microgels and gels formed by self-assembled amphiphilic triblock copolymers.

The degradation of (micro)gels and fractal aggregates based on self-assembled amphiphilic triblock copolymers has been investigated in water by confocal microscopy and light scattering respectively. The triblock copolymer consisted of a central hydrophilic poly(acrylic acid) (pAA) block and two hydrophobic end blocks that contained an equal amount of randomly distributed -butyl acrylate (BA) and AA units. These latter units helped at tempering the hydrophobic end blocks resulting in the control and the fine tuning of the dynamics of the self-assembled triblock through the pH.

Berberine-fluconazole microparticle-based combination therapy to treat candidiasis infections.

Aim: This study aims to incorporate alginate microparticles containing berberine and fluconazole into two different types of pharmaceutical formulations, to subsequently evaluate the antifungal activity against Candida albicans.

Methods And Results: Alginate microparticles containing BBR (berberine) and FLU (fluconazole) were produced by the spray-drying technique, characterized and incorporated in two pharmaceutical formulations, a vaginal cream and artificial saliva. Broth microdilution, checkerboard, time-kill curve, and scanning electron microscopy were carried out to determine the antifungal effects of BBR and FLU against C.

Model-Informed drug development of gastroretentive release systems for sildenafil citrate.

Gastroretentive drug delivery systems (GRDDS) are modified-release dosage forms designed to prolong their residence time in the upper gastrointestinal tract, where some drugs are preferentially absorbed, and increase the drug bioavailability. This work aimed the development of a novel GRDDS containing 60 mg of sildenafil citrate, and the evaluation of the feasibility of the proposed formulation for use in the treatment of pulmonary arterial hypertension (PAH), for once a day administration, by using in silico pharmacokinetic (PK) modeling and simulations using GastroPlus. The Model-Informed Drug Development (MIDD) approach was used in formulation design and pharmacokinetic exposure prospecting.

Structure of pH sensitive self-assembled amphiphilic di- and triblock copolyelectrolytes: micelles, aggregates and transient networks.

We have studied the self-assembly of aqueous dispersions of amphiphilic di- and triblock copolyelectrolytes using static and dynamic light scattering. The hydrophobic blocks contained both ionisable and hydrophobic units rendering the association dynamic and thus ensuring that thermodynamic equilibrium was reached. The incorporation of ionisable units into the hydrophobic blocks caused the self-assembly to be strongly influenced by the pH and the ionic strength.

Leishmania amazonensis: effects of oral treatment with copaiba oil in mice.

Leishmaniasis is a severe public-health problem, with high rates of morbidity and mortality. Efforts to find new, effective and safe oral agents for the treatment of leishmaniasis have been ongoing for several decades, in order to avoid the problems with the currently used antimonials. In the present study, we found that a copaiba oil oral treatment (Group IV) caused a significant reduction in the average lesion size (1.