Editing Crystal violet (section)

=== Science ===
[[File:Bacteria photomicrograph.jpg|thumb|right|[[Bacteria]] stained with crystal violet]]
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When conducting [[DNA]] [[gel electrophoresis]], crystal violet can be used as a nontoxic DNA stain as an alternative to [[Fluorescence|fluorescent]], intercalating dyes such as [[ethidium bromide]]. Used in this manner, it may be either incorporated into the [[agarose]] gel or applied after the electrophoresis process is finished. Used at a 10&nbsp;[[parts per million|ppm]] concentration and allowed to stain a gel after electrophoresis for 30 minutes, it can detect as little as 16&nbsp;[[Nanogram|ng]] of DNA. Through use of a [[methyl orange]] counterstain and a more complex staining method, sensitivity can be improved further to 8&nbsp;ng of DNA.<ref>{{cite journal|last1=Yang |first1=Y. |title=Counterion-dye staining method for DNA in agarose gels using crystal violet and methyl orange |journal=Electrophoresis |volume=22 |issue=5 |pages=855–859 |year=2001 |doi=10.1002/1522-2683()22:5<855::AID-ELPS855>3.0.CO;2-Y |pmid=11332752 |last2=Jung |first2=D. W. |last3=Bai |first3=D. G. |last4=Yoo |first4=G. S. |last5=Choi |first5=J. K.|s2cid=28700868 }}</ref> When crystal violet is used as an alternative to [[Fluorophore|fluorescent stains]], it is not necessary to use [[ultraviolet]] illumination; this has made crystal violet popular as a means of avoiding UV-induced DNA destruction when performing [[DNA cloning]] ''in vitro''.{{citation needed|date=December 2022}}

Crystal violet can be used as an alternative to [[Coomassie brilliant blue]] (CBB) in staining of [[protein]]s separated by [[SDS-PAGE]], reportedly showing a 5x improved sensitivity vs CBB.<ref name="Krause2019">{{cite journal |last1=Krause |first1=Robert G. E. |last2=Goldring |first2=J. P. Dean |year=2019 |title=Crystal violet stains proteins in SDS-PAGE gels and zymograms |journal=Analytical Biochemistry |publisher=Elsevier BV |volume=566 |pages=107–115 |doi=10.1016/j.ab.2018.11.015 |issn=0003-2697 |pmid=30458124 |s2cid=53944873}}</ref>

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The dye is used as a [[Staining|histological stain]], particularly in [[Gram staining]] for [[Bacterial taxonomy|classifying bacteria]].<ref>{{cite journal |last1=G |first1=Barbolini |last2=AC |first2=Pessina |date=1977 |title=Non-specificity of crystal violet staining for renin granules |journal=Acta Histochemica |publisher=Acta Histochem |volume=58 |issue=2 |pages=191–193 |doi=10.1016/S0065-1281(77)80127-X |issn=0065-1281 |pmid=70939}}</ref>

In [[Medical research|biomedical research]], crystal violet can be used to stain the nuclei of adherent cells.<ref>{{Cite journal |last1=Klingenberg |first1=Marcel |last2=Becker |first2=Jürgen |last3=Eberth |first3=Sonja |last4=Kube |first4=Dieter |last5=Wilting |first5=Jörg |date=2014-04-06 |title=The NADPH Oxidase Inhibitor Imipramine-Blue in the Treatment of Burkitt Lymphoma |journal=Molecular Cancer Therapeutics |volume=13 |issue=4 |pages=833–841 |doi=10.1158/1535-7163.mct-13-0688 |pmid=24482381 |doi-access=free}}</ref> In this application, crystal violet works as an intercalating dye and allows the quantification of DNA which is proportional to the number of cells.{{citation needed|date=December 2022}}

Crystal violet is also used as a [[Staining|tissue stain]] in the preparation of [[light microscopy]] sections.<ref>{{Cite journal |last1=Henneman |first1=Sheila A. |last2=Kohn |first2=Frank S. |date=June 1975 |title=Methylene blue staining of tissue culture monolayers |journal=Tissue Culture Association Manual |language=en |volume=1 |issue=2 |pages=103–104 |doi=10.1007/BF01352624 |issn=0361-0268 |series=Methods in Cell Science}}</ref> In laboratory, solutions containing crystal violet and [[formalin]] are often used to simultaneously [[Fixation (histology)|fix]] and stain cells grown in [[tissue culture]] to preserve them and make them easily visible, since most cells are colourless.

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It is also sometimes used as a cheap way to put identification markings on [[laboratory mice]]; since many strains of lab mice are [[albino]], the purple colour stays on their [[fur]] for several weeks.<ref name="AssalAN">{{cite journal|first=A. N. |last=Assal |title=Review on the Identification Methods of Laboratory Mice, Rats, Rabbits, and Guinea pigs |journal=Scandinavian Journal of Laboratory Animal Sciences |volume=15 |issue=1 |date=2019 |pages=19–31 |doi=10.23675/SJLAS.V15I1.697}}</ref>

In [[forensics]], crystal violet was used to develop [[fingerprint]]s. It is able to develop fingerprint marks from live human skin.<ref>{{Cite journal |last1=Feldman |first1=M. A. |last2=Meloan |first2=C. E. |last3=Lambert |first3=J. L. |date=1982-10-27 |title=A new method for recovering latent fingerprints from skin |url=https://pubmed.ncbi.nlm.nih.gov/7175462/ |journal=Journal of Forensic Sciences |volume=27 |issue=4 |pages=806–811 |doi=10.1520/JFS12196J |issn=0022-1198 |pmid=7175462}}</ref>