How To: Use the Unicam UV-visible spectrometer in the lab

The Department of Biological Sciences at the University of Alberta brings you this video tutorial specifically relevant to your student laboratory courses, specifically microbiology. If you're a student at any school of biology, this information will be helpful for learning how to use the Unicam UV-visible spectrometer, split beam and internal printer in the lab.

Part A: The spectrometer is turned on and left to warm up. Once warmed up the absorbance is set to scan from 320 to 230 nm by the dial.

Part B: Water is put into the cuvette for a blank and the cuvette is put in the first cuvette holder inside the spectrometer. The blank for this experiment is water. The liquid used may change depending on the experimental set-up.

Part C: The sample (DNA) is put into the second cuvette and placed inside the spectrometer. Notice that because this is a split beam spectrometer, the blank and the sample are in different cuvettes but both inside the spectrometer at the same time.

Part D: When the run button is pressed, the wavelength scans (notice the dial turning by itself) and the pen starts recording the change in Absorbance of the sample during the wavelength scan (cap must be off pen first!)

Important: These special cuvettes are very sensitive to fingerprints. The front and back of the cuvette (through which the beam passes) should never be touched. Two sides are rough and can be touched safely. Thus when holding a cuvette, ONLY the rough sides should be in contact with your fingers. Also the front and back of the cuvettes are wiped with a kimwipe to clean them.