Spatiotemporal and chemical dynamics of silver nanoparticles in the burn wound

Silver nanoparticles are innovative antimicrobial agents used in key applications related to the care of burns and chronic wounds, but their chemical in vivo dynamics in human tissues has not been directly observed so far.1-3 In this study, synchrotron radiation μXRF/μXANES and laser ablation ICP-MS were used to provide the first information on the spatiotemporal distribution and chemical speciation of silver in full-profile biopsies collected from the wound bed of burn patients treated with a dressing containing nanoparticles. A significant penetration of the metal was observed, inversely associated with the level of structural organization of the tissue, and accompanied by sequential processes of dissolution, chloride complexation, change into metal-thiol protein complexes, and final mobilization into deeper skin layers towards the vascular system. Hydrodynamic chromatography-single particle ICP-MS was used to confirm the high level of dissolved silver species and the absence of nanoparticles in the blood of analogous patients.4 The results provide new realistic bases to design innovative silver nanomaterials with optimal antibacterial efficacy and minimum risks for the patient.