Biological properties of sulfanilamide-loaded alginate hydrogel fibers based on ionic and chemical crosslinking for wound dressings.

In this work, alginate hydrogel fibers loading sulfanilamide were proposed using a combination of Ca2+ ions and glutaraldehyde crosslinking to develop an efficient wound dressing. The structure, mechanical properties, absorbency, in vitro drug release and cytotoxicity of the proposed alginate hydrogel fibers were investigated systematically. The results indicated that crosslinking with glutaraldehyde can efficiently enhance the mechanical properties of the alginate hydrogel fibers, and reduce their swelling degree which is beneficial for hydrogel fibers to obtain adjustable fluid adsorption capacity, sustained drug release feature over hydrogel fibers crosslinked only by Ca2+ ions. Antibacterial activity assay demonstrated the bactericidal ability of the alginate hydrogel fibers towards S. aureus and E. coli with the highest antibacterial rate of 99.9%. Furthermore, a preliminary trial of papermaking process for producing alginate hydrogel mats showed the workability and the applicability of the mechanically tough hydrogel fibers. Cytotoxicity assay indicated the enhancement of cell adhesion and proliferation, revealing the non-cytotoxicity and biocompatibility of the alginate hydrogel mats. Based on the excellent mechanical strength, adjustable fluid adsorption capacity, sustained drug release, and biocompatibility, the bi-crosslinked alginate hydrogel fibers had a promising application as ideal wound dressings in clinic.

Pharmacokinetics of the antimicrobial drug Sulfanilamide is altered in a preclinical model of vascular calcification.

In vascular smooth muscle, calcium overload is linked to advancing age. The pharmacokinetics of Sulfanilamide (SA), a compound with antibacterial properties, was evaluated in a preclinical model of vascular calcification. SA was used since it is useful to study possible modifications in the renal and hepatic management of drugs. Vascular calcification was induced by administration of a single high dose of vitamin D3 to rats (treated group) 10 days before the experiments. A parallel control group was processed. The decrease of renal blood flow due to calcification of the renal arteries explains, at least in part, the decrease in the renal clearance of SA observed in treated rats. The liver metabolic function increased in treated rats as demonstrated by increases in plasma appearance rate of acetylated-Sulfanilamide (ASA), hepatic ASA content and hepatic N-acetyltransferase activity. The decrease in renal excretion of SA was not completely compensated by the hepatic metabolism increase, since the elimination rate of SA from the central compartment (K1-0 ) decreased in the treated group. In summary, in this experimental model with sustained arterial calcinosis induced by a single high dose of vitamin D3 10 days before the experiments, the pharmacokinetics of an aminobenzenesulfonamide is modified, at least in part, by the increase in the activity of hepatic N-acetyltransferase and the decrease in renal blood flow. This study emphasizes the importance of considering the presence of vascular calcification when a drug dose scheme is performed, in order to optimize pharmacotherapeutic results.