Table 2. Photophysical properties of ASiP^j and NIR-ASiP^j derivatives.

	R 1 (alkyl)	R 2 (EWG)	Solvent	λ abs a /nm	ε b /M–1 cm–1	λ em c /nm	Φ F d
ASiPj1	Me	H	PBS	481	14 500	655	0.11 e
			EtOH	487	13 100	628	0.28 e
			CH3CN	488	12 300	640	0.26 e
			CH2Cl2	492	18 300	641	0.33 e
ASiPj2	Bn	H	PBS	501	13 100	656	0.10 e
			EtOH	502	14 800	632	0.31 e
			CH3CN	506	13 900	642	0.30 e
			CH2Cl2	512	15 900	645	0.32 e
ASiPj3	Propargyl	H	PBS	509	26 100	662	0.12 e
			EtOH	510	20 900	644	0.19 e
			CH3CN	515	32 000	654	0.18 e
			CH2Cl2	517	30 200	657	0.23 e
NIR-ASiPj1	Me	CO2Bn	PBS	702	109 500	715	0.05 f
			EtOH	702	114 800	717	0.35 f
			CH3CN	700	107 400	714	0.26 f
			CH2Cl2	702	102 600	718	0.40 f
NIR-ASiPj2	Me	COCH3	PBS	703	43 200	714	0.06 f
			EtOH	705	58 600	717	0.29 f
			CH3CN	700	52 700	713	0.25 f
			CH2Cl2	706	53 700	718	0.35 f
NIR-ASiPj3	Me	COCF3	PBS	711	79 500	724	0.04 f
			EtOH	713	90 600	728	0.27 f
			CH3CN	711	95 300	726	0.21 f
			CH2Cl2	715	87 400	730	0.32 f

^aMaximum absorption wavelength.

^bMolar extinction coefficient.

^cMaximum emission wavelength.

^dFluorescence quantum yields determined in CH₃CN using

^efluorescein (Φ = 0.95 in 0.1 M NaOH) or

^fNile blue (Φ = 0.27 in ethanol) as reference dyes.