Editing Cuvette (section)

== Technique ==
[[File:A cuvette in a spectrophotometer.jpg|alt=transparent side direct to the light in spectrometer|thumb|A cuvette in a spectrophotometer]]
Scratches on the sides of the cuvette that the light passes through scatter light and cause errors.<ref>{{Cite web |url=http://chemed.chem.purdue.edu/genchem/lab/equipment/spec20/cuvette.html |title=Cuvette |website=chemed.chem.purdue.edu |access-date=2016-03-17}}</ref> A rubber or plastic rack protects the cuvette from accidentally hitting and being scratched by the machine casing. The solvent and temperature can also affect measurements.<ref>{{Cite web |url=http://www.pharmaguideline.com/2011/05/handling-cleaning-storage-of-cuvettes.html |title=Handling, Cleaning & Storage of Cuvettes of Spectrophotometer |last=Choudhary |first=Ankur |date=2011-09-27 |website=www.pharmaguideline.com |language=en-US |access-date=2017-06-19}}</ref> Cuvettes to be used in [[circular dichroism]]<ref>[http://www.bioch.ox.ac.uk/aspsite/services/equipmentbooking/biophysics/introfluor.pdf Circular Dichroism (CD) Spectroscopy]. Applied Photophysics Ltd., 2011. Retrieved 15 August 2013.</ref> experiments should never be mechanically stressed, as the stress will induce [[birefringence]]<ref>Weisstein, Eric W. [http://scienceworld.wolfram.com/physics/Birefringence.html "Birefringence"]. ''scienceworld.wolfram.com'', Wolfram Research, 1996–2007. Retrieved 15 August 2013.</ref> in the quartz and affect measurements. Analyses are performed by using a conventional scanning spectrophotometer and the usual laboratory cuvette (special vial) that fits into the sample cavity of the instrument.<ref name="ramesh">{{Cite web |last=ramesh |date=2022-11-18 |title=Ultraviolet (UV) Visible Spectroscopy Principle |url=https://pharmaelix.com/ultraviolet-visible-spectroscopy-fundamentals/ |access-date=2022-11-19 |website=PharmaeliX |language=en-US}}</ref>

Fingerprints and droplets of water disrupt light rays during measurement, so low-lint [[gauze]] or cloth may be used to wipe clean the outer surface of a cuvette before use. Paper towel or similar may scratch the cuvette.  Mild [[detergent]] or [[ethanol]] may be applied, followed by rinsing with tap water.  Acid and alkali are avoided due to their corrosive effects on glass, and [[acetone]] is unsuitable when working with plastic cuvettes. If solution is transferred into a cuvette using a [[Pipette|Pasteur pipette]] containing air, bubbles may form inside the cuvette, reducing the purity of a solution and scattering light beams. The finger-clad finger method is used to remove bubbles. The solution contained in the cuvette should be high enough to be in the path of the light source.<ref>{{Cite web |url=http://www.cmscientific.com/cuvette_info.php |title=What Is A Cuvette? – How To Use A Cuvette |website=www.cmscientific.com |language=en |access-date=2017-06-19}}</ref> In case the sample needs incubation at a high temperature, care must be taken to avoid temperatures too hot for the cuvette.