Biopolymeric films as delivery vehicles for controlled release of hydrocortisone: Promising devices to treat chronic skin diseases.

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease with nasty effects on the psychosocial wellbeing of patients. Overall, glucocorticoids, such as hydrocortisone (HC), are the primary pharmacologic drugs used to treat AD and its symptoms. However, the long-term treatment with HC is often accompanied by severe adverse effects. So, this study reports the encapsulation of HC in polymeric films based on gelatin (Gel) and gelatin/starch (Gel/St) and investigates their potential to treat and attenuate 2,4-Dinitrochlorobenzene (DNCB)-induced AD-like symptoms in BALB/c mice model. The prepared films were characterized by different techniques, which indicated that HC was physically entrapped into the polymer matrices. In vitro experiments indicate that the HC release process occurs in a controlled manner (up to 48 h) for both films. Regarding the in vivo experiments, HC-loaded films (Gel@HC and Gel/St@HC), unloaded films (Gel and Gel/St) and HC cream (1%) (as reference) were applied topically on the back of the DNCB-sensitized animals and skin severity scores and scratching behavior were determined. Ex-vivo experiments were done to quantify inflammatory and/or biochemical parameters. As assessed, the topical application of the biopolymeric films (loaded or not with HC) improved the inflammatory parameters, while a lower corticosterone level was observed for the animals treated with Gel and Gel@HC films. In summary, the HC-loaded films showed superior efficiency to treat/attenuate the analyzed parameter than the HC cream (1%). Further, no death or sign of toxicity was observed in animals exposed to HC-loaded films. Thus, the encapsulation of HC in biopolymeric films seems to be a promising alternative for the treatment of injuries caused by chronic skin diseases that require prolonged use of glucocorticoids.

Preparation, characterization and antitumor activity of a cationic starch-derivative membrane embedded with a ß-cyclodextrin/curcumin inclusion complex.

A membrane of cationic starch-derivative/poly(vinyl alcohol) was prepared and utilized as a support to immobilize a ß-cyclodextrin/curcumin inclusion complex. The resulting material (denote as ß-CD/CUR-MBN) was characterized in detail by different techniques. In vitro experiments revealed that ß-CD/CUR-MBN enables the controlling of the curcumin release process, which is guided by the relaxation of the polymer matrix. Moreover, cytotoxic assays were performed to investigate the effect of ß-CD/CUR-MBN on two cancer cell lines (melanoma and glioblastoma). The results showed that the polymeric membrane exerts higher cytotoxicity against these cells than free curcumin. Also, ß-CD/CUR-MBN exerted a prolonged cytotoxic effect (up to 96 h), even using a low concentration (50 µg mL-1), indicating that the curcumin in the polymeric membrane showed increased bioavailability under the tested condition. ß-CD/CUR-MBN was non-cytotoxic against normal cells suggesting a specific action of this material against target cancer cells. The results reported here allow ranks ß-CD/CUR-MBN as a promising biomaterial to act as a local drug delivery system to treat cancer.

Synthesis of chitosan derivatives with organoselenium and organosulfur compounds: Characterization, antimicrobial properties and application as biomaterials.

In this study, Schiff bases of chitosan (CS) were synthesized using citronellal, citral, and their derivatives containing selenium and sulfur. Organoselenium and organosulfur compounds show attractive biological and pharmaceutical activities, which can be beneficial to CS-based materials. From the characterization analyses, it was found that the CS-derivatives containing organoselenium and organosulfur compounds exhibited the highest conversion degrees (23 and 28%). Biological assays were conducted using films prepared by the blending of CS-derivatives and poly(vinyl alcohol). The antimicrobial evaluation indicated that the film prepared with the sulfur-containing CS was the most active against the tested pathogens (Escherichia coli, Staphylococcus aureus, and Candida albicans) since it reduced considerably their counts (42.5%, 17.4%, and 18.7%). Finally, in vivo assays revealed that this film attenuates atopic dermatitis-like symptoms in mice by suppressing the increase of myeloperoxidase (MPO) activity and reactive species (RS) levels induced by 2,4-dinitrochlorobenzene (DNCB). In summary, CS-derivatives containing chalcogens, mainly organosulfur, are potential candidates for biomedical applications such as for the treatment of chronic skin diseases.

Polysaccharide-based film loaded with vitamin C and propolis: A promising device to accelerate diabetic wound healing.

Wound healing can be a painful and time-consuming process in patients with diabetes mellitus. In light of this, the use of wound healing devices could help to accelerate this process. Here, cellulose-based films loaded with vitamin C (VitC) and/or propolis (Prop), two natural compounds with attractive properties were engineered. The starting materials and the cellulose-based films were characterized in detail. As assessed, vitamin C can be released from the Cel-PVA/VitC and Cel-PVA/VitC/Prop films in a controlled manner. In vitro antibacterial activity studies showed a reduction of bacteria counts (Escherichia coli and Staphylococcus aureus) after Cel-PVA/VitC, Cel-PVA/Prop, and Cel-PVA/VitC/Prop treatments. Moreover, we examined the antibacterial and wound healing properties of the cellulose-based films in a streptozotocin (STZ)-induced diabetic animal model. Diabetic mice exhibited impaired wound healing while the Cel-PVA/VitC/Prop treatment increased the wound closure. A marked reduction in bacterial counts present in the wound environment of diabetic mice was observed after Cel-PVA/VitC, Cel-PVA/Prop and Cel-PVA/VitC/Prop treatment. Histological analysis demonstrated that the non-treated diabetic mice group did not exhibit adequate wound healing while the treated group with Cel-PVA/VitC and Cel-PVA/VitC/Prop films presented good cicatricial response. Furthermore, these novel eco-friendly films may represent a new therapeutic approach to accelerate diabetic wound healing.

Orange waste: A valuable carbohydrate source for the development of beads with enhanced adsorption properties for cationic dyes.

Eco-friendly pectin and pectin/cellulose microfibers beads (PB and PB-CF) were synthesized using compounds extracted from orange bagasse, a solid waste from the food industry. PB-CF beads showed remarkable differences regarding several properties as compared to the beads without CF. The adsorption capability of PB and PB-CF was tested towards the removal of methylene blue (MB) from aqueous solution. The effect of various parameters on the MB adsorption was investigated. The kinetics and mechanism of adsorption were explained by the pseudo-second-order kinetics and intra-particle diffusion models. Equilibrium adsorption data are explained by the Langmuir isotherm model, which revealed a maximum adsorption capacity of 1550.3mg/g for PB and 2307.9mg/g for PB-CF5. Thermodynamic analysis suggests that the adsorption of MB on the beads is spontaneous and favorable. Recycling study demonstrated that both PB and PB-CF5 can be implemented in 6 consecutive adsorption/desorption cycles without losing their adsorption capacity. These results enable the use of PB and PB-CF as potentially low-cost adsorbents for wastewater treatments.