Suva Method Procedure

Lysa Uwizeyimana
Updated August 2015

Specific Ultra-Violet Absorbance (SUVA)
SUVA or UV254 is an analytical technique used to measure the absorbance at different wavelengths, but commonly set at 254 nm. The Evolution 300 UV-Spectrophotometer is the instrument we use in this procedure and it is equipped with a touchscreen computer that we use to enter data, process it, and a USB port that can be used to extract data.
Apparatus and equipment:
  * Evolution 300 UV-Spectrophotometer
  * Test tubes
  * Quartz cuvettes
  * Kim wipes
  * Milli Q or DI water
Before using the Spectro:
  * Rinse out test tubes with 10% HCL once and three times with DI water, and leave them on a rack to dry.
  * Label the test tubes appropriately and pour in 5 ml of sample in each test tube.
  * Rinse each Quartz cuvette three times with Milli-Q
On the spectro:
  1. Hit the POWER button to start the computer on the spectro. Wait for about 3 min for it to start.
  2. Once the computer has started, Hit THERMO SCIENTIFIC, a shortcut found on the desktop.
  3. Wait for about a min for it pop up and hit Basic Fixed.
  4. Then Hit Home on the Left side of the screen, Go to Settings and set the required wavelength. A keypad should show up on the screen, if it doesn’t keep trying.
You may process the samples at different wavelengths simultaneously, for example: @245nm, @290nm and @ 456nm.
  5. Set the desired path length usually 1cm.
  6. On the upper right corner hit Samples. Add the number of samples you wish to add but moving ^ or v. A keypad should pop and allow you to Load in the sample names and the description. Remember to always start with a blank or CCV and Hit Zero on the Spectro.
  7. Prepare your first blank by pouring in milliQ in the rinsed cuvette up to the max line (Blue line) and wiping the cuvette several times to make sure there are no fingerprints or liquid.
  8. Open the spectro compartment, Hold the cuvette...