How should cuvettes be cleaned?

This is a common question without a fixed answer. In fact, it is hard to find any specific published methods. Why are there no specified methods?

The reason is because of the diverse variety of samples that are analyzed. Due to the wide variety of analytical samples, a wide variety of corresponding cleaning methods are required. However, since describing all methods is not realistic, it does not help solve the problem. Therefore, a few of the common cleaning methods are described below. These methods can be roughly categorized into few groups. One group uses water as the solvent and the other uses organic solvent.

1) Using Water as a Solvent - After cleaning with purified water, clean with ethanol and store dry. However, for more severe contamination, soak cells in a commercial cleaning solution made specifically for cleaning cells (for about 10 minutes at 30 to 50 °C). Then clean the cell with distilled water and soak them in a dilute solution of nitric acid and a small amount of hydrogen peroxide (for about 30 minutes). Finally, rinse the cell with distilled water and store cells dry.

2) Using Organic Solvents - After cleaning with the organic solvent being used, clean with ethanol or acetone and then clean using the same method as described for the aqueous solution above.

3) For stubborn contamination - the cell may be scrubbed lightly with a cotton swab. Avoid using alkaline cleaning solutions that can dissolve glass or ultrasonic cleaning devices that can damage the cell.