User:Keyun Wang/Notebook/Experimental Biological Chemistry I/2012/11/28

From OpenWetWare
Jump to navigationJump to search
Experimental Biological Chemistry I <html><img src="/images/9/94/Report.png" border="0" /></html> Main project page
<html><img src="/images/c/c3/Resultset_previous.png" border="0" /></html>Previous entry<html>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</html>Next entry<html><img src="/images/5/5c/Resultset_next.png" border="0" /></html>

Purpose

  • Au/ADA samples made on 2012/11/27 were ran on UV-vis spectrophotometer and Atomic Absorption Spectrometer, results were analyzed.
  • Au/ADA samples were resuspended in a range of Tris buffers to test resuspension based on concentration of buffer and pH.

Procedure for Running Au/ADA samples on UV-vis Spectrophotometer

  • 3mL of Au/ADA samples with the following mole ratios were analyzed using UV-vis spectrophotometer.
  60-70-80-90-100-110-120-130-140-150
  • 3mL of distilled water was run on UV-vis under spectrum method followed by test samples with above mole ratios. The absorbance obtained from wavelength range 200nm to 800nm were used as base line correction for the Au/ADA samples.
  • Both reference and test samples were loaded into quartz cuvette with 10.0mm pathlength.

Results for Running Au/ADA samples on UV-vis Spectrophotometer

  • The Au/ADA samples made with dialyzed ADA proteins all appeared purple with purple fiber formation at the bottom of tubes. A picture of the samples after 4 hours of heating is shown in picture below:

[Insert Picture]

  • The result indicated that the lack of salt in samples might have an affect on nanoparticle aggregation formation. The lack of salt in solution might lead to ADA proteins to wrap around gold in solution at a lower temperature. The formed gold nanoparticles might have different isoelectric points that engages protein aggregations.
  • While the fiber formation can be due to lack of salt in solution that encouraged nanoparticle aggregation, the fiber formation might also be affected by the usage of plastic falcon tubes during the reaction.
  • The absorbance obtained from UV-vis spectrophotometer were plotted on a graph for all Au/ADA samples. The graph was plotted with absorbance versus wavelength scanning from 200nm to 800nm shown below:

  • From the graph above, it can be shown that there the trend for all Au/ADA samples appeared similar, and that there were no significant difference in gold concentration between each Au/ADA samples solutions. This might indicate that the ratio between Au and dialyzed ADA in solution does not determine gold nanoparticle formation.
  • Comparing the all samples, including water, at a specific wavelength:525nm, it can be seen that there were no significant difference between water and all Au/ADA samples. A data table showing the samples run and absorbance at 525nm is shown below:
Au/ADA samples Absorbance at 525nm
0 0.039
60 0.041
70 0.039
80 0.04
90 0.037
100 0.038
110 0.037
120 0.04
130 0.038
140 0.037
150 0.036
Standard Deviation: 0.001566699
  • A graph is made with absorbance of each sample at wavelength 525nm versus water and all Au/ADA samples:

  • From the graph above, it can be concluded that there was no significant differences between the absorbance between water samples and each Au/ADA samples due to low standard deviation. This indicates that there is no relationship between the mole ratios of Au/ADA in solution and the gold nanoparticle formation in solution.
  • The data can be compared against the Au/ADA solution made on 2012/11/27.

Procedure for Running Au/ADA samples on Atomic Absorption Spectrometer

Results for Running Au/ADA samples on Atomic Absorption Spectrometer

Procedure for Au/ADA Resuspension in Tris Buffer

Results for Au/ADA Resuspension in Tris Buffer