Silver Nano Particles

Preparation and Bio toxicity

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

Practical Application

• Food and drink storage in ancient civilization• Surgical instrumentation• Ointments • Wound dressings• Cavity filling (amalgam)

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.

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

Electron Transfer and Release of CO2

Size Capping by Citrate

Color to look for

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.