# User:Allison K. Alix/Notebook/Thesis Research/2013/07/17

< User:Allison K. Alix‎ | Notebook‎ | Thesis Research‎ | 2013‎ | 07
Absorbance Measurements of AuNP@SiO2 <html><img src="/images/9/94/Report.png" border="0" /></html> Main project page
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## To Do

• Take absorbance spectra of AuNP@SiO2 samples
• Determine which concentrations are suitable for TEM imaging (Thursday)
• Repeat DNA/AuNP extraction procedure using optimum centrifugation speed and time (10,000 rpm for 11 minutes)

## DNA-AuNP attachment procedure

• Scale down to a final solution volume of 300uL due to minimal AuNP solution.

Calculating volumes of buffer, AuNP, and DNA for final solution:

[sodium citrate] = 268mM

268mM (x) = 10mM (300uL)

x = 11.2uL sodium citrate

(300uL-11.2uL)/2 = 144.4uL each of DNA and AuNP

Procedures:

1) Prepare 200uL 4.45uM DNA

53.1uM(x) = 200uL(4.45)

x = 16.8uL in 183.2uL 1X PBS

2) Mix DNA with 200uL DTT in TEA

3) React 10 minutes

4) Extract DNA using 4 2mL aliquots of ethyl acetate

5) Mix 144.4uL DNA with 144.4uL AuNP and 11.2uL sodium citrate

6) React 10 min

7) Centrifuge for 11 minutes @ 10,000rpm. Remove supernatant, redisperse in 50mM HEPES. Repeat 2 times.