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Just Add Water – reproducible singly dispersed silver nanoparticle suspensions



Robert I. MacCuspie, Andrew J. Allen, Matthew N. Martin, Vincent A. Hackley


Silver nanoparticles (AgNPs) are of interest due to their antimicrobial attributes, which are derived from their inherent instability and subsequent release of silver ions into solution. At the same time, this instability makes achieving stable long-term storage for on-demand use of AgNps technically challenging. In the present study we describe and validate a “Just Add Water” approach to achieving suspensions of singly dispersed AgNPs. By lyophilizing the AgNPs into a solid powder, or cake, water is removed eliminating solution-based chemical changes such as surface oxidation. An example of how to optimize a lyophilization formulation is presented, as well as example formulations for three diameters of AgNPs. This “Just Add Water” approach enables ease of use for the researcher desiring on-demand singly dispersed AgNP suspensions. Implementation of this methodology will enable studies to be performed over long periods of time and across different laboratories using particles that are identical chemically and physically and available on-demand.
Journal of Nanoparticle Research


Silver nanoparticles, lyophilization, freeze-dried nanoparticles


MacCuspie, R. , Allen, A. , Martin, M. and Hackley, V. (2013), Just Add Water – reproducible singly dispersed silver nanoparticle suspensions, Journal of Nanoparticle Research, [online], (Accessed May 29, 2024)


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Created June 19, 2013, Updated November 10, 2018