UV-visible absorption spectra of nAg-Col suspensions (10 mg Ag/l) with or without bacteria.

UV-Vis spectra of AgNPs in half-strength NaCl-free LB medium without bacterial cells (dashed red line) or after exposure of bacterial cells to nAg-Col (solid line). Before measurement, bacterial cells and cell-associated nanoparticles were removed by centrifugation at 4 000 g for 5 minutes. The difference between dashed and continuous lines shows the co-precipitation of nAg-Col particles with bacterial cells. The representative figures from the three independent experiments are shown.