The role of sodium citrate is to reduce silver nitrate to silver (1). The role of D-glucose was to reduce silver nitrate into just silver, while soluble starch stabilizes the nanoparticles by surrounding them to prevent aggregation (1, 2, 3).
The 1 M NaOH, 1 M HCl, and 1 M NaCl caused Batch A to aggregate. The nanoparticles aggregated with these reagents because these are all strong bases or strong acids, which dissociates completely and interacts with the oxidized citrate that separate the nanoparticles, destroying the “citrate shield” away. Thus, the nanoparticles were attracted to each other, and then aggregate. The distilled water, 1 M sucrose, and 1 M NaCl produced nanoparticles resistant to aggregation.
To synthesize 20 nm nanoparticles,
The 1 M NaOH, 1 M HCl, and 1 M NaCl caused Batch A to aggregate. The nanoparticles aggregated with these reagents because these are all strong bases or strong acids, which dissociates completely and interacts with the oxidized citrate that separate the nanoparticles, destroying the “citrate shield” away. Thus, the nanoparticles were attracted to each other, and then aggregate. The distilled water, 1 M sucrose, and 1 M NaCl produced nanoparticles resistant to aggregation.
To synthesize 20 nm nanoparticles,