By adding Aloe vera leaf extract to a synthetic hydrogel, researchers have synthesized a new kind of swollen hydrogel that can speed up wound healing by absorbing damaging ultraviolet rays1. This hydrogel could potentially be used as a medical patch for treating skin diseases.

The researchers synthesized the swollen hydrogel by adding different concentrations of Aloe vera leaf extract to hydrogels made from two cross-linked organic compounds: N-vinylpyrrolidone and acrylamide. They then explored the swelling properties and mechanical stability of the hydrogel.

The leaf-extract polysaccharides were found to be distributed throughout the gel matrix, imparting mechanical stability to the hydrogel. The number of nanopores in the hydrogel decreased with increasing leaf extract concentration. Adding the leaf extract at concentrations greater than 6.5 per cent, thinned the pore walls in the hydrogel, increasing their size.

However, at higher concentrations, the leaf extract polysaccharides exerted stress on the pore walls during swelling. This, in turn, cracked the pore walls and caused paths to form between the pore walls, enhancing water uptake.

The scientists probed the wound-healing potential of the hydrogel by exposing it to ultraviolet light in a pH 7 buffer solution. The hydrogel released flavonoids, which strongly absorbed the ultraviolet light.

This finding suggests that the hydrogel may accelerate wound healing by absorbing damaging ultraviolet rays, the researchers say.