How to Guide on Buying Spectrophotometer Cuvettes


Choosing a spectrophotometer cuvette for the first time can be a daunting experience. Following the simple guide below will allow researchers to quickly and easily select the correct cuvette for any experiment.

Spectrophotometer or Fluorometer Cuvette

The most basic question to answer when selecting a cuvette is what type of machine does it go in. If it goes into a spectrophotometer, then the two parallel windows need to be polished. If a researcher is using a fluorometer, than all four optical windows need to be polished. It is important to note that a spectrophotometer cuvette will not work in a fluorometer, but a fluorometer cuvette will work in a spectrophotometer.

What Material Is Best

Depending on the type of experiment, the material the cuvette is made out of is very important. For researchers working in the UV range, they need a special UV quartz that can transmit from 190-340 nm. The most common range that scientists work in is the visible or VIS range which is from 340-2,000 nm. For this range there are three different materials available based on a labs budget.

IR Quartz is the most expensive material which covers from 190-3,500 nm. Next comes UV Quartz covering 190-2,500 nm. And the most economical option for a VIS experiment is optical glass which covers 340-2,000 nm. If a researcher does not want to re-use a cuvette, then they can find disposable spectrophotometer cuvettes that can be thrown away after one use.

What Lightpath To Choose

Lightpaths are how many millimeters the light has to travel before it exits the spectrophotometer cuvette. Lightpaths can range from very small, ex. 0.01 mm, up to 200 mm. The biggest determing factor in selecting the proper lightpath is the size of the sample a researcher is using. If the researcher has a large sample, then a 10 mm lightpath is the industry standard. If a scientist has a small sample that is very expensive, such as DNA/RNA, then he should use a small lightpath cuvette to conserve his sample.

Putting it All Together

The three above factors, spectrophotometer cuvette or fluorometer cuvette, the material, and the lightpath are the three fundamentals needed to choose a cuvette.

Once a researcher has answered these three questions they are ready to choose the more simple features such as what type of cover is best for the experiment.

Following these three simple guidelines makes choosing a spectrophotometer cuvette very easy, even for new grad students.


Source by Simcha Woitovich