Direct evidence for uptake of intact liposomes encapsulating silver sulfadiazine by cultured human keratinocytes based on combined transmission electron microscopy and X-ray microanalysis.

Cultured human keratinocytes were exposed to liposomally encapsulated silver sulfadiazine, free silver sulfadiazine, silver sulfadiazine cream, and a corresponding vehicle for 5 min to 24 h. Phagocytosis of intact liposomes by keratinocytes was demonstrated in vitro by combined X-ray microanalysis and electron microscopy. Silver as an active part of the antimicrobial served as an electron-dense marker.