Publications

Wound infections affect 2% of the global population, causing chronic wounds and healthcare burdens as conventional antibiotics increasingly fail against biofilms. Consequently, attention is shifting toward advanced dressings that simultaneously prevent infection and support tissue regeneration. Among these, fibrous drug delivery systems have emerged as promising platforms for localized and controlled therapeutic delivery. Beyond platform geometry, physicochemical properties of the polymers are paramount in establishing biocompatibility, tunable degradation kinetics, and adequate mechanical integrity. PLGA and PLA/PCL-based nanofibrous platforms exhibit these favorable characteristics, even though they are still limited by issues such as limited control over release kinetics and potential instability of bioactive agents during fabrication. To address the limitations, hybrid platforms combining electrospun nanofibers with drug-loaded nanoparticles have been developed to provide structural integrity and secondary drug reservoirs for sustained release. Here, we developed a dualcarrier hybrid delivery platform to overcome burst release kinetics and achieve sustained local therapeutic levels by integrating microfluidically synthetized nanoparticles with electrospun nanofibrous matrices. To systematically elucidate the role of scaffold structure on the in-vitro performances, two delivery strategies were investigated: (i) direct entrapment of therapeutics within electrospun PLGA and PLA/PCL fibers, and (ii) surface coating of electrospun mats with PLGA nanoparticles. This study uses these approaches to encapsulate a hydrophobic agent, curcumin (CURC), a natural antimicrobial agent with limited solubility, and hydrophilic peptide, bovine lactoferricin (bLFC), which requires protection from enzymatic degradation. The use of these naturally derived compounds offers a promising non-antibiotic strategy to mitigate antibiotic resistance while promoting wound healing.

JTD Keywords: Antimicrobial agents, Biofilms, Curcumin, Dissolution profile, Dressings, Electrospinning, Hybrid scaffolds, Mechanisms, Microfluidics, Penetrant diffusion, Release, Solute, Swellable polymers, Wound infection

Designing useful functionalities in clinically validated, old antibiotics holds promise to provide the most economical solution for the global lack of effective antibiotics, as undoubtedly a serious health threat. Here we show that using the surface chemistry of the cyclodextrin (beta CD) cycle and arginine (arg) as a linker, provides more stable ternary antibiotic complex (beta CD-arg-cpx). In contrast to classical less stable inclusion complexes, which only modify antibiotic solubility, here-presented ternary complex is more stable and controls drug release. The components of the complex intensify interactions with bacterial membranes and increase the drug's availability inside bacterial cells, thereby improving its antimicrobial efficacy and safety profile. Multifunctional antibiotics, formulated as drug delivery systems per se, that take the drug to the site of action, maximize its efficacy, and provide optical detectability are envisaged as the future in fighting against infections. Their role as a tool against multiresistant strains remains as interesting challenge open for further research.; Ternary cyclodextrin- arginine- ciprofloxacin complexes show improved stability and increased efficacy against P. aeruginosa in Galleria mellonella worms.

JTD Keywords: Antibiotic-resistance, Beta-cyclodextrin, Dissolution, Drugs, Salts

We have studied the preparation of Cu2O films by copper anodization in a 0.1 M NaOH electrolyte. We identified the potential range at which Cu dissolution takes place then we prepared films with different times of exposure to this potential. The morphology, crystalline structure, band gap. Urbach energy and thickness of the films were studied. Films prepared with the electrode unexposed to the dissolution potential have a pyramidal growth typical of potential driven processes, while samples prepared at increasing exposure times to dissolution potential present continuous nucleation, growth and grain coalescence. We observed a discrepancy in the respective film thicknesses calculated by coulometry, atomic force microscopy and optical reflectance. We propose that anodic Cu2O film formation involves three parallel mechanisms (i) Cu2O nucleation at the surface, (ii) Cu+ dissolution followed by heterogeneous nucleation and (iii) Cu+ and OH- diffusion through the forming oxide and subsequent reaction in the solid state.

JTD Keywords: Cuprous oxide, Anodic films, Reflectance, Thickness, Band gap, Urbach tail parameter, Dissolution, Growth mechanism