User:Melissa Novy/Notebook/CHEM-571/2012/11/13

Objectives

• Analyze Au-HRP solutions with UV-vis spectroscopy.
• Analyze solutions of Au-HRP and Au-lysozyme with AAS.
• Conduct ADA activity assay on ADA fractions using adenosine.

ADA Activity Assay

• 50 mL of 0.05 M sodium phosphate buffer was made with deionized water. The pH of the solution was adjusted to 7.4 using 3 drops of 12 M HCl.

• 5 mL of 0.1 mM adenosine was made.
  • 100 mg of adenosine was dissolved in 1 mL of 0.05 M phosphate buffer, giving a solution of 0.00373 M adenosine.
  • 0.134 mL of 0.00373 M adenosine was diluted to a final volume of 5 mL with 0.05 M phosphate buffer, giving a solution of 0.1 mM adenosine.

  (0.001 g)/(268.02 g/mol) = 3.73×10-6 mol
  (3.73×10-6 mol)/0.001 L = 0.00373 M
  (0.00373 M)(V1)=(5 mL)(0.1×10-3 M)
  V1 = 0.134 mL

Atomic Absorption of Au-Lysozyme and Au-HRP Solutions

• The Au-lysozyme solutions were made on 2012/10/31.
• The Au-HRP solutions were made on 2012/11/07.

• Gold was detected in solutions at mole ratios of Au-lys from 20 to 60. The 60 Au-lys solution had the highest concentration of gold. This agrees with UV-vis data obtained on 2012/11/06. However, no peak or a slight peak was visible on the spectrum of the 20 Au-lys solution. This is corroborated by the fact that the AAS detected that the solution contained 0.0057 ppm Au.
• It can be assumed that the fibers formed in the rest of the Au-lys solutions at mole ratios from 70 to 130 encapsulated the gold, such that there was no free gold or gold nanoparticles in solution. Theoretically, the gold concentration in these solutions was zero, but the AAS registered negative concentrations due to the fact that it was blanked with 1 N HCl, as opposed to deionized water.