Using the Varian Eclipse Fluorimeter

Emission Spectrum

1. Power up the Eclipse with the switch on the front panel, if necessary. The dim light on the front will become green when ready.
2. If the computer is not logged in, log into "Fluorimeter" by clicking on its icon.
3. Double click on the Scan icon on the desktop THEN Click on the Setup button.
4. Set the excitation wavelength to either of the absorption maxima in the UV-Vis spectrum
5. Set the scan limits. The starting wavelength for the emission spectrum should be 30 nm above the excitation wavelength to avoid Rayleigh scattering. The upper wavelength should be 700nm.
6. The scan speed should be set to Slow (120 nm/minute) and both slits should be set to 10nm.
7. Click on the Reports tab. Set the Threshold value to 5. Click the OK button.
8. Click on the green traffic light icon to start the scan.
9. A window will appear where you can name your sample. Put in your desired name and click OK.
10. When the scan is complete, print the spectrum by clicking on the Print button.

Excitation Spectrum

1. Obtain excitation spectrum by repeating the above steps, start by clicking the Setup button. Click on the box that says excitation.
2. Set the emission wavelength to the value you determined above.
3. Record the excitation spectrum from 280nm to about 30nm below the emission wavelength.
4. Collect excitation spectra under the identical conditions for the milk sample you prepared.