Cuvettes Plastic & Glass

A cuvette (sample cell, absorption cell) is, in its basic level, fundamentally a test tube designed for use with optical analysis. Standard cuvettes are generally square or rectangular in cross section to avoid refraction artefacts. Depending on what part of the spectrum is under consideration, they may be made of quartz or optical glass although plastic cuvettes do exist for less demanding measurements.
The other types of cuvettes are more expensive than the plastic cuvette. It is disposable and will be eliminated once complete the spectrometric experiment to prevent risk from reusing cuvettes and damaging expensive quartz. Color and UV range can be analyzed by this type of cuvette. The smallest one are capable of holding 70µl, the medium size contains between 1.5ml and 3.0ml, and the biggest is for testing samples with 2.5ml or larger.[1] Some cuvettes will be clear only on opposite sides, so that they pass a single beam of light through that pair of sides; often the unclear sides have ridges or are rough to allow easy handling. Cuvettes to be used in fluorescence spectroscopy[2] must be clear on all four sides because fluorescence is measured at a right-angle to the beam path to limit contributions from beam itself. Some cuvettes, known as tandem cuvettes, have a glass barrier that extends 2/3 up inside, so that measurements can be taken with two solutions separated, and again when they are mixed. Typically, cuvettes are 10 mm (0.39 in) across, to allow for easy calculations of coefficients of absorption. To measure the sample, the transparent side must be placed toward the light in spectrophotometer. For accurate measurement, these testing tubes should be cleaned and without any scratches.[3] Cuvettes to be used in circular dichroism[4] experiments should never be mechanically stressed, as the stress will induce birefringence[5] in the quartz and affect the measurements made.