Question

Question: What is the active ingredient present in Tea responsible for the reduction of AuNps?

Experiment: Synthesize gold nanoparticles of ~ 10-15nm size using Tea leaves as a reducing agent.

Synthesis:

Step 1: In a 20 ml vial, 0.012g of Gum Arabic was dissolved in 6ml of doubly ionized water D (I).

Step 2: 100mg of Tea leaves (Lipton Loose Tea) was added to the above solution. The reaction mixture was stirred continuously at 25 C for 15 min.

Step 3: To the stirring mixture was added 100 μl of 0.1 M NaAuCl4 solution (in DI water). The color of the mixture turned purple-red from pale yellow within 10 minutes indicating the formation of gold nanoparticles.

Step 4: The reaction mixture was stirred for an additional 15 minutes. The gold nanoparticles thus formed were separated from residual tea leaves immediately using a 5 micron filter.

Answer 1