Exploring the Impact of Alginate-PVA Ratio and the Addition of Bioactive Substances on the Performance of Hybrid Hydrogel Membranes as Potential Wound Dressings

Abstract

Healthcare professionals face an ongoing challenge in managing both acute and chronic wounds, given the potential impact on patients' quality of life and the limited availability of expensive treatment options. Hydrogel wound dressings offer a promising solution for effective wound care due to their affordability, ease of use, and ability to incorporate bioactive substances that enhance the wound healing process. Our study aimed to develop and evaluate hybrid hydrogel membranes enriched with bioactive components such as collagen and hyaluronic acid. We utilized both natural and synthetic polymers and employed a scalable, non-toxic, and environmentally friendly production process. We conducted extensive testing, including an in vitro assessment of moisture content, moisture uptake, swelling rate, gel fraction, biodegradation, water vapor transmission rate, protein denaturation, and protein adsorption. We evaluated the biocompatibility of the hydrogel membranes through cellular assays and performed instrumental tests using scanning electron microscopy and rheological analysis. Our findings demonstrate that the biohybrid hydrogel membranes exhibit cumulative properties with a favorable swelling ratio, optimal permeation properties, and good biocompatibility, all achieved with minimal concentrations of bioactive agents.

Keywords: bioactive; biohybrid; collagen; dressing; healing; hyaluronan; hydrogel; wound.

Figure 1

Initial evaluation of hydrogel formulations showing cumulative properties of hybrid hydrogel membranes, (A) swelling index, (B) gel fraction, and (C) hydrolytic degradation (dH₂O, pH 7.4). Swelling index assay displays high SD due to variable disintegration rates of hydrogel samples during the study. Results are presented as mean ± S.D.

Figure 2

Visual representation of different biohybrid hydrogel membranes (BH). Note the transparency.

Figure 3

Moisture content and moisture uptake for biohybrid hydrogel membranes (BH) compared to hybrid hydrogel membranes (H). Results are presented as mean ± S.D.

Figure 4

Swelling ratio of biohybrid hydrogel membranes (BH) to that of hybrid hydrogel membranes (H). Results are presented as mean ± S.D.

Figure 5

In vitro biodegradation study for biohybrid hydrogel membranes (BH) compared to hybrid hydrogel membranes (H) using distilled water (dH₂O, pH 7.4), SWF (pH 8.3), HAasa (10 U/mL), COLasa (10 U/mL) and mixture of HAasa + COLasa (10 U/mL each). Results are presented as mean ± S.D.

Figure 6

Gel fraction of biohybrid hydrogel membranes (BH) compared to that of hybrid hydrogel membranes (H). Results are presented as mean ± S.D.

Figure 7

Water vapor transmission rate of biohybrid hydrogel membranes at 24 and 48 h. Results are presented as mean ± S.D.

Figure 8

Protein adsorption study at 24 h. The amount of BSA that remained after removing the hydrogels was assayed spectrophotometrically using the Bradford method. The protein uptake was evaluated indirectly, taking into account the initial and equilibrium concentrations of BSA in the solution, as well as dimensions as the samples. Results are presented as mean ± S.D.

Figure 9

Inhibition of protein denaturation. Different hydrogel formulations were incubated in a BSA 5% solution at 37 °C, 15 min, then 70 °C for 70 min and cooled down to 25 °C. The samples were removed and the absorbance of the remaining BSA solution was spectrophotometrically assayed at 278 nm, using an aspirin solution (0.5 mg/mL) as a control. Results are presented as mean ± S.D.

Figure 10

Cytotoxicity determined via LDH assay. Normal human fibroblasts were incubated with mentioned gel formulations. LDH release was measured spectrophotometrically in the cell supernatant. Readings were normalized to background for each formulation and expressed as ratio to normalized lysis control. Results are presented as mean ± S.D.

Figure 11

Surface morphology of hybrid hydrogel membranes (H) and biohybrid hydrogel membranes (BH) after 48 h of drying at 55 °C.

Figure 12

Morphology of cross-section of hybrid hydrogel membranes (H) and biohybrid hydrogel membranes (BH) after 48 h of drying at 55 °C.

Figure 13

Mechanical properties of sample H1 compared to sample BH1.80 depending on moisture content. (A): Young’s modulus (N/mm²), (B): elongation at break (%), (C): tensile strength (N/mm²). For each formulation at least eight samples were analyzed in triplicate. Results are presented as mean ± S.D.