The Open Materials Science Journal

2015, 9 : 113-118
Published online 2015 August 27. DOI: 10.2174/1874088X01509010113
Publisher ID: TOMSJ-9-113

Research on Syntheses and Properties of Water-soluble Symmetrical Squarylium Double-cyanine Dyes

Xinding Yao , Ruina Fang , Hongjian Pang and Guoji Liu
Environment and Chemistry Engineering Department of Yellow River Conservancy Technical Institute, Kaifeng, 475004, Henan, China.

ABSTRACT

In this paper, 2,3,3-trimethyl-3H-indolin was synthesized by phenylhydrazine and 3-methyl-2-butanone as raw materials in the acetic acid reacted with different nitrogenalkylating reagents. Semi mono-cyanine dye and semi dicyanine dye were prepared with the help of squaric acid diethyl ester. The spectral properties of the target products were checked. The results show that compared with symmetrical squarylium mono-indocyanine dyes with the same substituent, the photo-stability of the bi-cyanine dyes were much better. When dissolved in water, the dye showed shorter maximum absorption wavelength, shorter maximum emission wavelength and shorter Stokes shift and apparent aggregation. In protic solvents, dye spectra showed a blue shift effect with an increase of solution polarity, while in aprotic solvents, dye spectrum showed a red shift with solution polarity increased. Among different solvents, the photostability of the dye in methanol is strongest.

Keywords:

Cyanine dye, fluorescent labeling.