Comparison of Wound Healing Effects of Different Micro-Patterned Hydrogels on the Skin of Secondary Intention Rat Model

Background: The skin acts as a barrier against external threats, and moisture is crucial for effective wound healing, as it promotes epithelial cell migration. Thus, a high water content supports wound healing by maintaining moisture, absorbing exudate, and forming a protective barrier. Here, we created three different micro-patterned hydrogels and tested them on rat skin wounds. Materials and Methods: Three different micro-patterned (waves, lines, and checks) hydrogel patches were created using three-dimensional polymer networks. On SD rat skin, wounds were created by making incisions, and the hydrogel patches were applied. The rats were divided into three experimental groups based on the hydrogel micro-patterns. Rats without hydrogel (vehicle) and those with flat hydrogel (no shape) were considered as controls. The wound closure rate (WCR) was calculated, and the expression of Col1A protein was measured by western blot. Results: After 7 days, the WCR was significantly higher in the groups treated with micro-patterned hydrogel patches compared to the vehicle and no-shape groups. Specifically, the WCR was highest in the checks micro-patterned hydrogel group compared to the waves and lines micro-patterned hydrogel groups. Furthermore, Col1A protein expression was evaluated at days 7 and 14, revealing a significant increase in expression after 14 days in the checks micro-patterned hydrogel group compared to the waves and lines micro-patterned hydrogel groups. Conclusions: The checks micro-patterned hydrogel patches demonstrated superior wound healing efficacy, as indicated by a higher WCR and increased Col1A protein expression after 14 days. These findings highlight the importance of hydrogel pattern design in improving wound healing suggesting that optimized micro-patterns can enhance therapeutic outcomes in skin wound management.