A significant number of deaths are reported annually worldwide due to microbial and viral infections. The development of protective medical textiles for patients and healthcare professionals has attracted many researchers’ attention. Therefore, this study aims to develop smart drug-eluting nanofibrous matrices to be used as a basic material for medical textile fabrication. First, chitosan/gelatin nanofibers were selected as the basic material owing to the wide antimicrobial activity of chitosan and the capability of gelatin to be hydrolyzed in the abundance of the papain-like protease (PLpro) enzyme secreted by SARS-CoV-2. Daclatasvir (DAC), an NS5A inhibitor, was selected as the model drug based on in silico studies where it showed high anti-SARS-CoV-2 potential compared to FDA-approved references. Due to their reported antimicrobial and antiviral activities, ZnO NPs were successfully prepared and incorporated with daclatasvir in chitosan/gelatin nanofibrous matrices through electrospinning. Afterward, an in vitro release study in a simulated buffer revealed the controlled release of DAC over 21 days from the nanofibers compared to only 6 h for free DAC. On the other hand, the abundance of PLpro induced the complete release of DAC from the nanofibers in only 4–8 h. Finally, the nanofibers demonstrated a wide antimicrobial activity against S. aureus, E. coli, and C. albicans.

Background/Objectives: Direct intratumoral injection of doxorubicin (DOX) can increase local drug exposure, but rapid escape from the tumor limits retention and contributes to systemic toxicity. This study developed a thermoreversible chitosan/β-glycerophosphate (CS/β-GP) hydrogel designed to form an in situ depot and prolong local DOX delivery. Methods: A three-factor Box–Behnken design was used to optimize CS, β-GP, and DOX concentrations against gelation temperature, gelation time, viscosity, and 7-day cumulative release. The optimized formulation was characterized by rheology, injectability, degradation, swelling, porosity, and 4T1 cytotoxicity. Intratumoral retention, plasma and organ biodistribution, antitumor efficacy, body-weight changes, and cardiac toxicity were then evaluated in 4T1 tumor-bearing BALB/c mice. Results: The optimized hydrogel contained 1.684% w/v CS, 6.601% w/v β-GP, and 0.200% w/v DOX, gelled at 36.3 ± 0.55 °C within 1.65 ± 0.28 min, and released 84.66 ± 8.38% of DOX over 7 days. DOX-loaded hydrogel preserved concentration-dependent cytotoxicity. During in vivo studies, hydrogel delivery lowered the observed plasma DOX peak by approximately 55% and retained measurable intratumoral DOX for 168 h, whereas free DOX solution was no longer detectable. Tumor growth suppression was sustained, with tumor volumes of 205.62 ± 36.85 versus 701.69 ± 69.35 mm³ for free DOX solution on day 24. Repeated hydrogel treatment also markedly attenuated cardiac troponin-I (cTnI) and creatine kinase-MB (CK-MB) elevations relative to free DOX solution. Conclusions: Thermoreversible CS/β-GP delivery reshaped DOX exposure from a rapidly dispersing intratumoral dose into a sustained local depot, improving tumor control while reducing the early plasma peak and attenuating cardiac-injury biomarker elevations.