Asymmetric Janus\nNanofibrous Agar-Based Wound Dressing\nInfused with Enhanced Antioxidant and Antibacterial Properties

In the present study, we have developed an agar-based\nasymmetric\nJanus nanofibrous wound dressing comprising a support and an electrospun\nlayer with antibacterial and antioxidant properties, respectively,\nto facilitate healing effectively. The support layer containing agar\nand silver nitrate was fabricated by using solvent casting for sustained\nrelease, combating the dose-dependent cytotoxicity of silver nanoparticles,\nwhere nanoparticles were synthesized using a one-pot reduction method.\nThe electrospun layer, fabricated with a mixture of agar and polycaprolactone\ninfused with gallic acid, was electrospun over the support layer to\nimpart antioxidant properties. Characterizations using UV–vis\nspectroscopy, transmission electron microscopy, scanning electron\nmicroscopy, and Fourier transform infrared spectroscopy validated\nthe synthesis of nanoparticles in 10–20 nm diameter and the\nasymmetric Janus dressing. The developed Janus nanofibrous structure\nexhibited 98% porosity, excellent fluid-handling properties, a moisture\npermeability of 1200 g/m<sup>2</sup>/day, and a water absorption of\n∼250%. Moreover, the time-kill assay confirmed potent bacteriostatic\neffect against Gram-positive and Gram-negative bacteria, and sustained\nrelease of silver nanoparticles followed the Korsmeyer–Peppas\nmodel. With over 90% free radical scavenging efficacy, 37% degradation\nin 7 days, and less than 2% hemolysis, the dressings demonstrated\nexceptional antioxidant, biodegradable, and hemocompatible properties.\nThe biocompatibility assessment further confirmed its cytocompatible\nefficacy, with more than 79% wound closure in the wound scratch assay.\nMost importantly, in vivo studies demonstrated the efficacy of the\ndeveloped Janus dressing, promoting over 97% healing within 12 days\nof injury with higher epithelial formation. Overall, the in vitro\nand in vivo assessment of the developed Janus dressing confirmed its\npotential to function as a versatile and effective material for wound\ncare applications.