Design and characterization of AgVO3-HAP/GO@PCL ceramic-based scaffolds for enhanced wound healing and tissue regeneration

Abstract

Rapid, infection-free wound healing remains a critical challenge in regenerative medicine. This study presents the fabrication and evaluation of multifunctional electrospun polycaprolactone (PCL)-based scaffolds incorporating silver vanadate (AgVO₃), hydroxyapatite (HAp), and graphene oxide (GO) for advanced wound care applications. AgVO₃ offers potent antibacterial properties, HAp supports osteogenic and regenerative activities and GO enhances both mechanical performance and cellular interactions. The scaffolds exhibited a highly porous nanofibrous structure, mimicking the extracellular matrix (ECM) and promoting cell attachment, migration, and nutrient exchange. Comprehensive physicochemical characterization using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and field-emission scanning electron microscopy (FE-SEM) confirmed the successful integration of the composite. Mechanical testing revealed that GO-containing scaffolds significantly improved stiffness, with AgVO₃/GO@PCL and HAp/GO@PCL achieving Young's moduli of 5.82 MPa and 4.36 MPa, respectively, which are substantially higher than that of neat PCL (1.39 MPa). In terms of flexibility, HAp/GO@PCL displayed the highest elongation at break (107.54%), indicating exceptional stretchability. The ultimate tensile strength was also enhanced in HAp@PCL (0.80 kJ/m³) and AgVO₃/@PCL (0.88 kJ/m³), highlighting their capacity to resist mechanical stress during application. Contact angle measurements showed that the AgVO₃-HAp/GO@PCL scaffold had the highest hydrophilicity (65.58° ± 5.97), compared to pure PCL (89.89° ± 3.70), indicating improved wettability, which is critical for fluid management and cell-material interactions at the wound interface. In vivo wound healing studies using a full-thickness rat model demonstrated that AgVO₃/GO@PCL scaffolds achieved 50% wound closure within 3 days, while AgVO₃-HAp/GO@PCL scaffolds facilitated complete re-epithelialization by day 14. Histological analysis confirmed enhanced collagen deposition and organized tissue architecture. The scaffolds also exhibited strong antibacterial activity, with large inhibition zones against S. aureus and E. coli. These findings position AgVO₃-HAp/GO@PCL scaffolds as promising candidates for next-generation wound dressings, offering a robust combination of mechanical resilience, bioactivity, antimicrobial efficacy, and moisture balance tailored for clinical wound-healing applications.

Fig. 1

Stages of Scaffold preparation

Fig. 2

SXRD of a PCL, b HAP@PCL, c AgVO₃@PCL, d AgVO₃-HAP @PCL, e AgVO₃/GO@PCL. f HAP/GO@PCL and g AgVO₃-HAP/GO@PCL nanocomposites. (i) Full range of 2θ and (ii) magnified view of the 2θ region from 20° to 35°; vertical dashed lines indicate reference positions for characteristic diffraction peaks of each phase

Fig. 3

i FTIR spectra of a PCL, b HAP@PCL, c AgVO₃@PCL, d AgVO₃-HAP @PCL, e AgVO₃/GO@PCL. f HAP/GO@PCL, and g AgVO₃-HAP/GO@PCL. (ii) The schematic illustration highlights the molecular interaction between PCL chains, GO sheets, and HAP

Fig. 4

Raman spectra of a PCL, b AgVO₃-HAP @PCL, and c AgVO₃/GO@PCL. d HAP/GO@PCL, and e AgVO₃-HAP/GO@PCL

Fig. 5

FE-SEM micrographs of a AgVO₃-HAP @PCL, b AgVO₃/GO@PCL, c HAP/GO@PCL, and d AgVO₃-HAP/GO@PCL (inset is a 3D schematic model of the composit). yellow dashed circles show AgVO₃ rods, red dashed circles show nHAp and blue dashed circles show GO. A fiber diameter histogram is inserted for each scaffold

Fig. 6

3D FE-SEM topography images of electrospun scaffolds: a AgVO₃-HAP@PCL, b AgVO₃/GO@PCL, c HAP/GO@PCL, and d AgVO₃-HAP/GO@PCL

Fig. 7

Mechanical properties of the electrospun scaffolds. a Stress-strain curve, b Young’s modulus, c Elongation at breakdown (%) and d Ultimate strength (MPa) of the prepared samples of PCL, HAP@PCL, AgVO₃@PCL, AgVO₃-HAP @PCL, AgVO₃/GO@PCL, HAP/GO@PCL, and AgVO₃-HAP/GO@PCL

Fig. 8

Static water contact angle measurements of the fabricated scaffolds. a Bar graph showing the average contact angle (in degrees) for PCL, HAP@PCL, AgVO₃@PCL, AgVO₃-HAP@PCL, AgVO₃/GO@PCL, HAP/GO@PCL, and AgVO₃-HAP/GO@PCL. The dashed line at 90° indicates the threshold between hydrophilic ( < 90°) and hydrophobic ( > 90°) behaviors. b Representative contact angle images of water droplets on each scaffold surface

Fig. 9

Antibacterial performance of electrospun scaffolds against S. aureus and E. coli. a Inhibition zone diameters for PCL, HAP@PCL, AgVO₃@PCL, AgVO₃-HAP @PCL, AgVO₃/GO@PCL, HAP/GO@PCL, and AgVO₃-HAP/GO@PCL. b Schematic representation of the antibacterial mechanism, illustrating AgVO₃ nanorods embedded in the PCL matrix, releasing Ag⁺ ions

Fig. 10

Macroscopic evaluation of wound healing over 14 days in the different treatment groups. Images were captured at Days 0, 3, 6, 10, and 14 for PCL, HAP@PCL, AgVO₃@PCL, AgVO₃-HAP @PCL, AgVO₃/GO@PCL, HAP/GO@PCL, and AgVO₃-HAP/GO@PCL

Fig. 11

Wound closure at day 3,6, 10 and 14 for PCL, HAP@PCL, AgVO₃@PCL, AgVO₃-HAP @PCL, AgVO₃/GO@PCL, HAP/GO@PCL, and AgVO₃-HAP/GO@PCL

Fig. 12

Representative photomicrographs of H&E- stained skin tissue sections at 14 days’ post-surgery. Each black dotted line in all images indicates the boundary between the wound (left) and the surrounding normal intact skin (right). Stratified squamous keratinized epithelium (blue arrows). The glandular structure along with hair follicles (black arrows). Newly formed blood vessels (red arrows). Inflammatory cells (circle). a control, b PCL, c HAP@PCL, d AgVO₃@PCL, e AgVO₃-HAP @PCL, f AgVO₃/GO@PCL g HAP/GO@PCL, and h AgVO₃-HAP/GO@PCL (10X)

Fig. 13

Representative photomicrographs of Masson’s trichrome-stained skin tissue sections at 14 days’ post-surgery. Each black dotted line in all images indicates the boundary between the wound (left) and the surrounding normal intact skin (right). Stratified squamous keratinized epithelium (blue arrows). The glandular structure along with hair follicles (black arrows). Newly formed blood vessels (red arrows). Scale bars=50 µm a control, b PCL, c HAP@PCL, d AgVO₃@PCL, e AgVO₃-HAP @PCL, f AgVO₃/GO@PCL g HAP/GO@PCL, and h AgVO₃-HAP/GO@PCL (10X)

Fig. 14

Quantitative histological analysis of wound healing parameters across different scaffold groups :a Cell density, b collagen density, c epidermal thickness (µm), d epidermal thickness, e vessel density, and f hair follicle density