1. Preparation and Bio toxicity
Silver Nano Particles
Preparation and Bio toxicity

2. Why Silver? Silver is known to be bio toxic.
Silver ions and neutral atoms disrupts cell membranes and causes cell ruptures
Once inside the cell, silver binds to mitochondrial membrane and disrupts energy yielding reaction, i.e. energy (ATP) production in the cell.
Hence, silver ions and neutral atoms can kill bacteria

3. Practical Application
Food and drink storage in ancient civilization
Surgical instrumentation
Ointments
Wound dressings
Cavity filling (amalgam)

4. What are nano particle? Why nano?
Atomic silver (uncharged) particles that are less than 100 nm in diameter
Nano particles can disrupt
cell membranes more
locally, more effective in
bio toxicity.

5. Redox Reaction 2 Ag+ (aq) + 2 e- -----> 2 Ag(s)
Citrate ion >
acetone – 1,3- dicarboxylate + CO2 (g) + 2 e-
______________________________________ +
2 Ag+(aq) + Citrate ion ----->
2 Ag(s) + acetone-1,3-dicarboxylate + CO2

6. Electron Transfer and Release of CO2

7. Size Capping by Citrate

8. Color to look for

9. Acknowledgement
Drs. Elizabeth Hagar-Barnard and Rashmi Nanjundaswamy for spearheading the project
National Science Foundation for providing the funding
Maria Escudero, Brian Williams, Rodolfo Orellana and Charlene Cuellar for their assistant.