Figure 4From: Antimicrobial activity of spherical silver nanoparticles prepared using a biocompatible macromolecular capping agent: evidence for induction of a greatly prolonged bacterial lag phaseAbsorbance and first derivative spectra of keratin-capped Ag Np s at 4 dilutions. λ max is an average of the 4 derivatives (at ∂OD /∂λ = 0).Back to article page