4LSC2873 SQ-COOH CAS# 1643764-44-6

Catalog Number: 4LSC2873
CAS #: 1643764-44-6
Name: SQ-COOH, (Z)-4-((1-(3-carboxypropyl)-3,3-dimethyl-3H-indol-1-ium-2-yl)methylene)-2-(((Z)-1-ethyl-3,3-dimethylindolin-2-ylidene)methyl)-3-oxocyclobut-1-en-1-olate

SQ-COOH is a carboxylic acid far-red squaraine type fluorogenic building block that is useful in the design of probe in biosensing and bioimaging project.


  • Polarity-sensitive fluorogenic building block (Turn-on fluorophore)
  • Absorption & emission in the far-red  (630-700 nm) that enables in vitro & in vivo application
  • High brightness owing to its high molar extinction coefficient Ɛ~330000 M-1cm-1
  • High chemical stability & photostability

For high turn-on response fluorophore analog of SQ-COOH: Check out SQpeg-COOH !

  • Molecular Formula: C32H34N2O4
  • Molecular Weight: 510.6 g/mol
  • Specification: Minimum purity: 95.0 %

Squaraine as a bright, stable and environment sensitive far-red label for receptor-specific cellular imaging. Chem. Commun., 51, 2960-2963 , 2015doi:10.1039/C4CC09113B

Fluorogenic Squaraine Dimers with Polarity-Sensitive Folding As Bright Far-Red Probes for Background-Free Bioimaging.
J. Am. Chem. Soc., 137 (1), 405–412, 2015. doi:10.1021/ja5111267