Photophysical properties of CinNapht 5a.

Entry	Solvent	E T(30)a	λ max absb (nm)	ε max (M−1 cm−1)	λ max Em (nm)	Stokes shift (cm−1)	QYc	Life time (ns)
1	Hexane	31.0	469	12 200	520	2091	0.01	0.37
2	Toluene	33.9	480	12 000	550	2652	0.09	0.88
3	Dioxane	36.0	477	21 000	572	3482	0.16	1.89d
4	CHCl3	39.1	489	15 700	566	2782	0.25	2.23
5	DCM	40.7	488	16 400	591	3571	0.33	3.67
6	DMSO	45.1	496	15 500	682	5499	0.06	1.26d
7	EtOH	51.9	493	15 200	667	5291	0.05	0.84
8	MeOH	55.4	492	15 100	681	5640	0.02	0.47d
9	RPMIe	n.a.	496	n.d.f	675	5346	<0.01	n.d.
10	RPMIe + 10% FBS	n.a.	493	n.d.f	651	4923	0.02g	n.d.
11	In cell	n.a.	475	n.a.	590	4104	n.d.	n.d.
12	Solid	n.a.	491	n.a.	581	3446	n.d.	n.d.

^aPolarity coefficient of solvents based on literature.¹⁷

^bValues corresponding to S₀–S₁ transition but strong S₀–S₂ transition is also observed (see ESI Fig. S6 to S13).

^cRelative QY determined at 25 °C using [Ru(bpy)₃]Cl₂ (QY = 0.04 in air saturated H₂O).¹⁸

^dFitted by a biexponential function, the value indicated is an average lifetime. (For more details see ESI Fig. S5 and experimental section). In dioxane the two lifetime were 1.66 ns and 3.31 ns. In DMSO the lifetime were 1.13 ns and 2.21 ns. In MeOH the lifetime were 2.68 ns and 0.42 ns.

^eSolubility in aqueous medium such as RPMI culture medium (Roswell Park Memorial Institute medium), without phenol red, was found to be quite poor and required 5% of DMSO.

^fA small part of precipitation was observed that could not enable an accurate determination of ε.

^gValues observed by adding 10% of Foetal Bovine Serum (FBS) in RPMI medium.