Table 1.

Fluorescence lifetimes in vitro (Ex/em: 773/830 nm, 2-exponential fit)

Entry	Solvent	Lifetime, ns	%	χ2
4a	DMSO	4.02	97	1.21
	albumin/water	3.89	92	1.80
4a′	DMSO	3.35	97	1.55
	albumin/water	2.95	96	1.32
ICG	DMSO	1.11	96	1.15
	albumin/water	0.80∗	98	1.22

See footnote (20) and Berezin et al. (27) for experimental details.

^∗From three exponential fits.