LODs of fluorescent probes toward CO.

Probe	LOD	Probe	LOD	Probe	LOD	Probe	LOD
31	1000 nM	38	7.77 nM	45	3.2 nM	52	6.1 nM
32	653 nM	39	37 nm	46	62 nM	53	16 nM
33	720 nM	40	46 nM	47	30.8 nM	54	440 nM
34	60 nM	41	25 nM	48	255 nM	55	10 nM
35	50 nM	42	58 nM	49	3.2 nM
36	230 nM	43	57 nM	50	15.8 nM
37	No	44	38 nM	51	600 nM