Figure 9.

Zeta potential determination³⁸,³⁹ to evaluate Ag–NP stability over time. (A) Zeta potential varies with the repetition rate as measured after 24 hours. Maximal stability was achieved with the 30 Hz repetition rate; (B) evaluation of Ag–NP stability produced at 30 Hz repetition rate in aqueous starch solution over a period of 1 month (samples stored at ambient temperature in the dark). Generally, in aqueous starch solution, good stability is achieved and is retained contrary to colloids produced in water.

Abbreviation: Ag–NP, silver nanoparticles.