A hybrid oxygen-generating wound dressing based on chitosan thermosensitive hydrogel and decellularized amniotic membrane.

Amniotic membrane (AM) has been utilized as a wound dressing extensively. Given the importance of oxygen in wound healing, here we have reported the fabrication and characterization of an oxygen-generating wound dressing based on AM. This construct was composed of H2O2-loaded polylactic acid (PLA) microparticles embedded within a chitosan/ß-glycerophosphate (ß-GP) thermosensitive hydrogel covered with a layer of decellularized human-AM. The microparticles had a diameter of 4.48 ± 1.8 µm, an encapsulation efficiency of 44.172 ± 4.49%, and generated oxygen for at least 7 days. The hybrid construct was formed at 32.4 ± 2 °C, had a porous structure (84.69 ± 8.34%) with a pore size of 46.72 ± 26.21 µm. The hydrogel/dAM extract was non-toxic after 7 days based on our MTT results, and the final composite supported cell growth and adhesion. This sample had the most negligible blood cell adhesion with less than 5% hemolysis. Our results indicate the proposed structure's desirable biological, chemical, and physical properties as an active wound dressing.

A Review on Modifications of Amniotic Membrane for Biomedical Applications.

The amniotic membrane (AM) is the innermost layer of the fetal placenta, which surrounds and protects the fetus. Its unique structure, in addition to its physical and biological properties, makes it a useful substance in many applications related to regenerative medicine. The use of this fantastic substance with a century-old history has produced remarkable results in vivo, in vitro, and even in clinical studies. While the intact or preserved AM is widely used for these purposes, the addition of further modifications to AM can be considered as a relatively new subject in its applications. These modifications are applied to improve AM properties, ease of handling, and durability. Here, we will discuss the cases in which AM has undergone additional modifications besides the required processes for sterilization and preservation. In this article, we have categorized these modifications and discussed their applications and results.