Near‐Infrared Squaraine Dyes as Bright Fluorescent Probes: A Structure–Activity Photophysical Investigation in Liposomes
作者:Giacomo Renno、Francesca Cardano、Viktoria Ilieva、Guido Viscardi、Andrea Fin
DOI:10.1002/ejoc.202200833
日期:2022.10.7
unsymmetrical red emitting squaraine dyes is reported, varying the substituents to modulate the hydrophilic/hydrophobic ratio of the fluorescentprobes. Their ability to stain cellular membranes is assessed by studying their interactions with liposomal model systems, screening the key features for the design of squaraine-based cell membrane probes.
Synthesis, photophysical study and BSA association of water-insoluble squaraine dyes
作者:Diego dos Santos Pisoni、Marluza Pereira de Abreu、Cesar Liberato Petzhold、Fabiano Severo Rodembusch、Leandra Franciscato Campo
DOI:10.1016/j.jphotochem.2012.11.013
日期:2013.1
In this work, the synthesis, spectroscopic characterisation, photophysical study and bovine serum albumin association of water-insoluble squaraine dyes are described. The photophysical behaviour of the dyes was investigated using UV-vis and steady-state fluorescence in solution, as well as its association with bovine serum albumin in phosphate buffer solution. No squaraine aggregation was observed in organic solvents, but J-type aggregation could be observed in phosphate buffer solution. In the absence of protein, the J-aggregation promoted the fluorescence quenching; however, upon addition of protein, the fluorescence intensity increased by a factor of up to 80. Additionally, a linear relationship between the fluorescence intensity and the protein concentration could be observed for the squaraine dyes in a concentration range around 0.02-0.10 mu M. (C) 2012 Elsevier B.V. All rights reserved.
An N-butyl indolenine squarylium dye could include toluene and p-xylene and exhibited the solid-state fluorescence in near-infrared region (F-max=761 nm) in crystalline form due to inhibition of pi/pi-interactions between the fluorophores. (C) 2011 Elsevier Ltd. All rights reserved.