The use of silver as antimicrobial has recently established itself as a bxirgeoning market, being one of the most widely used additives in food applications. However, its potential use in active food packaging has not yet been exploited, In the present work, silver ions from a salt compound of the metal were satisfactorily incorporated into polylactic acid (PLA) matrices by a solvent casting technique. The ions did not affect the crystalhnity, water permeability or water-induced plasticization of the materials and were homogeneously distributed along the surface and thickness of the films. Colour measurements of the films revealed good transparency for all the samples. Release kinetics of the silver ions was monitored after daily rinsing of the films with water by a voltammetric approach and were tailored by different coatings. Antimicrobial assays according to the broth dilution method in M9 medium reported a bactericidal effect of the films after daily washings during 6, 30 and 60 days for films with 0.01%, 0.1% and 1% silver, respectively. These results represent a step forward in the understanding of silver antimicrobial efficacy and its possible application in the food packaging industry.
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