The lecithin/chitosan nanoparticles were prepared using four types of chitosan that differed in terms of molecular weight (50–150 or 150–400 kDa) and/or deacetylation degree (75–90 or >90%).

For all lecithin/chitosan nanoparticles prepared biphasic prolonged melatonin release was obtained.

The model wounds were treated with nanoparticle suspensions at a chitosan concentration determined in preceding cell biocompatibility studies.

Nanoparticles prepared with different types of chitosan showed similar effect on the keratinocyte proliferation/migration.

Nanoparticle-mediated interplay of chitosan and melatonin was shown to be crucial for improved wound epithelialisation.