Cuvettes are tube shaped containers and are having either circular or square cross section. They are designed to hold various types of samples required for experiments involving the measure of absorption of the given sample. The absorbance obtained using spectrophotometer instrument is also called optical density.
These cuvettes are used for general purpose of measuring absorbance of sample in colorimeters and UV-Visible Spectrophotometers. Absorbance is the amount of light absorbed by the sample. The absorbance depends on concentration of the particles in the sample and also the path length and molar absorptivity coefficients.
Since absorbance is dependent on the above mentioned factors, experiments should be conducted carefully so that there is no error caused by changing the path length i.e., by maintaining the same cuvette for each trial. Also lid is used to cover the cuvette so that atmospheric particles don’t mix with the sample and give error prone absorbance.
Cuvettes are manufactured in a variety of clear materials to support different wavelength range and path length requirements. The cuvette to be used will depend on the available range of wavelength and the sample volume. We use Hellma Cuvettes which are made up of both glass and quartz material. There are various types of glass cuvettes and the most important criterion for the choice of a particular type of glass is the spectral range for which that cuvette is intended. Glass cuvettes are used for measuring absorbance in visible region and quartz cuvettes is used both in the UV and visible region. The thermal expansion of quartz is extremely low and is chemically very resistant.
FirstSource Laboratory Solutions also provide Hellma Absorption cells for flow through measurements. Flow through cells allows the continual monitoring of optical parameters in processes such as reaction monitoring, tablet dissolution tests.
Advantages
- Easier handling of hazardous substances
- Individual adaptation to your substances
- Pressure resistant
- Graduated measurement results due to capture of bubble
- Connection options for flow through cells
There are different types of absorption cuvettes viz., Ultra micro cells – with PE stopper; Cells for Magnetic stirrers – macro, semi-micro, with PTFE lid or stopper; Sealable cells – macro, semi micro for anaerobic applications; Cells with Tubes – macro; Cylindrical Cells – macro; Temperature controlled cells – macro; Demountable cells – cells with detachable windows.
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