| Honey/CS/gelatin HS |
The HS containing honey swelled and reached equilibrium within 5 min compared to those without honey (30 min). CS and honey exert synergistic antimicrobial activity against Staphylococcus aureus and Escherichia coli (100% inhibition rate even after 3 days). HS demonstrated complete healing in burn wounds for approximately 12 days, compared to 14 days with commercial burn ointment (MEBO® ointment). Honey accelerates HS degradation under high temperatures (burn wounds), dispersing honey into the water. Honey reduces the stiffness of HS. With 20% honey, HS was found to mimic the mechanical behavior of natural skin, providing a desirable tissue repair environment.
|
[83] |
| Honey/CS/gelatin hydrogel |
As gelatin mass increased from 10 to 20 g, the crosslinking between CS and gelatin reduced from 68.86% to 65.68%, respectively, attributed to the reduced polycationic site exposure of CS, restraining ionic bond formation between CS's cationic ammonia and gelatin's carboxylate groups, reducing the hydrogel's mechanical strength. Honey further reduced gel fraction by disturbing the ionic interaction between CS and gelatin. Honey interfered with the hydrogen bond formation between water molecules and the crosslinked CS/gelatin network, reducing the swelling index. CS increased the swelling index of the hydrogel from 300% to 400%, likely due to the increased amine (‐NH‐) and hydroxyl (−OH) groups of CS, hastening hydrogen bond interaction with water, thereby improving water absorption capability. Instead of honey, CS was reported to be responsible for the hydrogel's antimicrobial activity toward E. coli and mold, aligning with another study.
84
|
[85] |
| Honey/CS/PVA hydrogel |
The crosslinking of PVA with CS promoted greater swelling capacity than that of pure PVA hydrogel due to the increased hydrophilic functional groups (−OH and ‐NH‐) contributed by CS. Adding CS into PVA hydrogel, which is naturally non‐antimicrobial, was also shown to increase the antibacterial activity where E. coli grows on plates with PVA hydrogel but not with CS.
|
[86] |
| Honey/CS/PVA DN‐Hyd |
CS acts as the first polyelectrolyte gel network and PVA as the second neutral network, while honey acts as a modifier for its excellent biodegradability and biocompatibility. CS increases the mechanical and tensile strength and elongation at break values, enhancing the hydrogel's stretchability for wounds with various sizes. Honey was previously shown to expedite PVA hydrogel's thermal degradation due to its low thermal stability and reduce the hydrogel's water content (swelling behavior), but these were mitigated by CS inclusion. The biocompatibility of the DN‐Hyd system was confirmed with the absence of altered cell morphology in treated cells.
|
[87] |
| Honey/CS/PVA hydrogel |
The tensile strength of the hydrogel resembles average human skin at 21.6 ± 8.4 MPa, a crucial property of wound dressing that mimics naturally healthy skin, preventing hydrogel tearing upon stretching. However, the presence of honey can also reduce the tensile strength and increase elasticity due to the possible role of honey as a plasticizer in PVA/CS hydrogel. The sustained biocompatibility of the hydrogel was excellent at above 70% cell viability in vitro post‐30‐day incubation, possibly attributed to the saccharides of honey as nutrients for the cells. The PVA/CS/honey hydrogel revealed a staggering 98% wound closure compared to the control group at 89%, indicating its remarkable effectiveness in treating wounds.
|
[50] |
| Honey/CS/PVA hydrogel |
The hydrogel's moisture content and swelling ratio increased with increasing CS concentration. The hydrogel has higher mechanical properties than pure PVA or CS hydrogel due to the complementary strong crosslinking interactions between CS and PVA, rendering them a controllable drug delivery system via sustained release of honey (drug) from the hydrogel. CS reduced WVTR which is crucial in wound healing by retaining moisture within and between hydrogel and wound beds. The hydrogel exhibited synergistic antimicrobial properties against S. aureus (5.01 ± 0.32 mm diameter of ZOI).
|
[88] |
