Oil Red O

Oil Red O

Differentiated adipocytes in a 3T3-L1 cell line stained with Oil Red O
Names
IUPAC name 1-(2,5-dimethyl-4-(2,5-dimethylphenyl) phenyldiazenyl) azonapthalen-2-ol
Identifiers
CAS Number	1320-06-5^Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:88213^N
ChemSpider	14217961^Y
ECHA InfoCard	100.013.906
MeSH	oil+red+O
PubChem CID	5841742
UNII	G7S71FND9B^Y
CompTox Dashboard (EPA)	DTXSID301039601 DTXSID90889366, DTXSID301039601
InChI InChI=1S/C26H24N4O/c1-16-9-10-17(2)22(13-16)27-28-23-14-19(4)24(15-18(23)3)29-30-26-21-8-6-5-7-20(21)11-12-25(26)31/h5-15,31H,1-4H3/b28-27+,30-29+^Y Key: NPGIHFRTRXVWOY-XOXGWFOHSA-N^Y InChI=1/C26H24N4O/c1-16-9-10-17(2)22(13-16)27-28-23-14-19(4)24(15-18(23)3)29-30-26-21-8-6-5-7-20(21)11-12-25(26)31/h5-15,31H,1-4H3/b28-27+,30-29+ Key: NPGIHFRTRXVWOY-XOXGWFOHBH
SMILES Cc4cc(/N=N/c1cc(C)c(cc1C)/N=N/c2c3ccccc3ccc2O)c(C)cc4
Properties
Chemical formula	C26H24N4O
Molar mass	408.49496
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references

Oil Red O (Solvent Red 27, Sudan Red 5B, C.I. 26125, C₂₆H₂₄N₄O) is a lysochrome (fat-soluble dye) diazo dye used for staining of neutral triglycerides and lipids on frozen sections and some lipoproteins on paraffin sections. It has the appearance of a red powder with an absorbance maximum at 518 nanometers.^[1]

Uses

Oil Red O is one of the dyes used for Sudan staining. Similar dyes include Sudan III, Sudan IV, and Sudan Black B. The staining has to be performed on fresh samples, as alcohol fixation removes most lipids. Oil Red O largely replaced Sudan III and Sudan IV, as it provides much deeper red color and the stains are therefore much easier to see.

Oil Red O can be used to mark lipid-containing vacuoles, particularly in cases of acute lymphoblastic leukemia or Burkitt's lymphoma. It can also be used to stain liver sections for histological analysis, quantify cell lipid content, and to stain the aorta to examine lesions from atherosclerosis.^[2]

In pyrotechnics, Oil Red O is used in some compositions of red colored smokes.

Forensic

When staining, Oil Red O can make fat more visible in various cuts in pathology.^[3]

It is also used in a technique (the method is called as the dye: Oil Red O), discovered in 2004 by Alexandre Beaudoin, for staining latent fingerprints.^[4] This technique allows the development of latent fingerprints on porous exhibits (such as paper, cardboard, etc.) that are dry or wet.

It mainly targets fat deposits on the surface of porous exhibits.^[5] It is a non-destructive technique (which does not destroy the exhibit nor prevents the use of other techniques).

It is a safe alternative to the Physical Developer method,^[6] and is also used in sequence with other methods of fingerprints development.^[7]

References

1. Kraus, Nils A.; Ehebauer, Franziska; Zapp, Benedikt; et al. (2016). "Quantitative assessment of adipocyte differentiation in cell culture". Adipocyte. 5 (4): 351–358. doi:10.1080/21623945.2016.1240137. ISSN 2162-3945. PMC 5160397. PMID 27994948.
2. "Oil Red O". MilliporeSigma. Retrieved 15 February 2023.
3. "Forensic Pathology".
4. Triplett M, Fingerprint Dictionary, Two Rings Publishing, Bellevue, Washington.
5. Beaudoin, A. New technique for revealing latent fingerprints on wet, porous surfaces: Oil Red O. Journal of Forensic Identification, 2004, 54 (4), 413-421.
6. Rawji, A. ; Beaudoin, A. Oil Red O versus Physical Developer on wet papers: a comparative study. Journal of Forensic Identification, 2006, 56 (1), 33-54.
7. Guigui, K.; Beaudoin, A. The use of Oil Red O in sequence with other methods of fingerprint development. Journal of Forensic Identification, 2007, 57 (4), 550-581.

External links

• Stains File entry
• [1]