User:Sanuja Mohanaraj/Notebook/Experimental Biochemistry 1 Fall 2017/2017/10/24

From OpenWetWare
Jump to navigationJump to search
Project name Main project page
Previous entry      Next entry

Characterization of the Clay Exchanges and TiO2-AuNP

Clay Exchanges
After drying, the four clay samples were washed using 10mL aliquots of water and ethanol, five times using the centrifuge on the third floor. The clays were then spread onto watch glasses in a thin layer, before placing them in the oven at 105°C to ensure that the clays were fully dry. The four clay samples were then ground to fine powder using a mortar and pestle. The samples were then characterized using x-ray diffraction between 2° and 50°.

Unfortunately, none of our clay samples were close to weighing 0.3 grams, so our group were not able to prepare the clay-supported gold nanoparticles.

TiO2-AuNP
After heating, the TiO2-AuNP was ground using a mortar and pestle, before characterizing using x-ray diffraction between 2° and 50°. Next, the TiO2-AuNP was used to selectively oxidize glycerol by first placing 0.2g of the sample into a 100mL round-bottomed flask. ~1g of glycerol and ~29mL of methanol, and 0.75g of NaOH were then added into the round-bottomed flask. A balloon was then filled with ~500mL of oxygen by reacting half a teaspoon of yeast with 10mL of 3% H2O2 in a flask with a holed stopper. The balloon was then placed onto the mouth of the flask, to introduce oxygen into the reaction. The reaction was left aside for ~2 hours.

The balloon was then removed and centrifuged, to separate and recover the TiO2-AuNP.

X-Ray Diffraction Spectroscopy

Clay Exchange Samples



The figures above display the x-diffraction spectra of the four different clay samples. The first figure depicts the diffraction spectrum of the histidine clay-exchange sample, with a sharp and intense peak observed at ~7.3 degrees 2θ. The second figure displays the diffraction spectrum of the lysine clay-exchange sample, with two broad, subtle peaks observed at ~5 degrees 2θ and ~7 degrees 2θ respectively. The third figure depicts the diffraction spectrum of the tryptophan clay-exchange sample, with a sharp and intense peak observed at ~7.5 degrees 2θ. The final figure displays the diffraction spectrum of the arginine clay-exchange sample, with a sharp and intense peak observed at ~7 degrees 2θ.

AuNP-TiO2 Sample


The figure above displays the diffraction spectrum of the AuNP-TiO2 sample, with four sharp distinct peaks observed at ~25.5 degrees 2θ, ~27.5 degrees 2θ, ~38 degrees 2θ, and lastly ~48 degrees 2θ.

Infrared Spectroscopy

Clay-Exchange Samples



The figures above display the transmittance spectra for each of the four different clay-enchange samples. The first figure displays the transmittance spectrum of the arginine cay-exchange sample, with a sharp and intense peak observed at ~1000 wavenumbers. The second figure represents the transmittance spectrum of the histidine clay-exchange sample, with a sharp and intense peak observed at ~1006 wavenumbers. The third figure depicts the transmittance spectrum of the lysine clay-exchange sample, with a sharp and intense peak, observed at ~1000 wavenumbers, followed by an additional peak at ~1700 wavenumbers. The final figure depicts the transmittance spectrum of the of the tryptophan clay-exchange sample, with a sharp and intense peak observed at ~1000 wavenumbers.

AuNP-TiO2 Sample


The figure above depicts the transmittance spectrum of the AuNP-TiO2 sample, with a subtle peak observed at ~1600 wavenumbers, followed by a broader peak at ~3300 wavenumbers.