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The development of wound dressings with therapeutical benefits is of great importance in skin tissue engineering applications, adding bioactive molecules into biomaterials is a strategy to achieve a better biological response. In this study, four different concentrations of curcumin (CUR; 5, 10, 15 and 20 by weight in relation to the PCL content) were incorporated into solutions composed of polycaprolactone (PCL) and collagen (COL) for the manufacture of electrospun fibers. The PCL-COL-CUR fibers were physicochemically characterized in terms of their morphology, wettability, degradation rate, mechanical behavior, and cumulative curcumin release. The in vitro biological properties of the composite membranes were also evaluated. The results indicated that the membranes have diameters on average of approximately 200 nm. The water uptake was adequate for exudates remotion in a wound, and the degradation rate of the fibers was highly appropriate to achieve complete skin tissue regeneration. The addition of CUR to composite membranes produced a significant increase in the mechanical properties which indicate a satisfactory clinical handling. The incorporation of CUR produced a significant decrease in the planktonic growth of S. aureus over time, however, the antibacterial effect against E. coli was limited, the presence of CUR did not cause the inhibition of its growth. Finally, the viability of human dermal fibroblasts seeded on the top of the membranes indicated the cytotoxic dosage effect of CUR, the two highest CUR concentrations produced a significant loss of cell viability. Overall, our results suggested that the CUR-loaded PCL-COL composite membranes are promising candidates for use as antibacterial dressings to enhance clinical wound management. [ABSTRACT FROM AUTHOR]

Sodium acetate trihydrate (SAT) is used as a phase change material (PCM) because of its high latent heat of fusion. Mixtures were prepared with SAT, a blend of the polymer sodium carboxymethil cellulose (CMC) and silica gel, silver nanoparticles (AgNPs), and anhydrous sodium sulfate to form a composite-PCM (c-PCM) based on SAT; the relative proportions of CMC/silica gel in the blend and AgNP content were varied according to a central composite experimental design. The thermal properties were determined for raw SAT, CMC, $$\hbox {Na}_{2}\hbox {SO}_{4}$$ , and c-PCM samples. The thermal effusivity $$(e_\mathrm{s})$$ of samples was evaluated by the inverse photopyroelectric technique. The thermal diffusivity $$(D_\mathrm{s})$$ was obtained for samples by the open photoacoustic cell technique. The thermal conductivity $$(k_\mathrm{s})$$ was calculated from the obtained $$e_\mathrm{s}$$ and $$D_\mathrm{s}$$ values. To assess the thermal performance of the c-PCM compared to raw SAT, samples were studied through differential scanning calorimetry which served to determine the latent heat recovery ( LHR). Properties $$e_\mathrm{s}, D_\mathrm{s}, k_\mathrm{s}$$ , and LHR were analyzed by response surface methodology and compared. The SAT-based c-PCM was found to be more thermally conductive than raw SAT. The best LHR with good thermal diffusivity and thermal conductivity was identified in the region of the central composite experimental design with medium-low AgNPs and higher proportions of CMC in the polymer blend. [ABSTRACT FROM AUTHOR]