Table 1.

Composition and properties of sensing membranes doped with one of the three ionophores Mn-1, Mn-2 and Mn-3 in different ratios of ionic sites and ionophore.

Sensing Membrane No.	Ionophore (L)	Ionic sites (RzR,char)		Detection Limits/M	CO32− selectivity ( $log{K}_{{co}_3^{2-},J}^{\mathit{pot}}$)
		zR,char	[RzR,char]/Ltot		SCN−	HO−	BPh4−
1a	Mn-1	+1	2:3	2.0 × 10−5	−1.59 ± 0.16	1.07 ± 0.16	8.54 ± 0.22
2a	Mn-1	+1	4:3	1.7 × 10−5	5.60 ± 0.20	3.21 ± 0.24	17.30 ± 0.33
3b	Mn-1	−1	1:4	1.9 × 10−5	3.28 ± 0.20	5.14 ± 0.13	3.72 ± 0.12
4a	Mn-2	+1	2:3	5.2 × 10−5	0.46 ± 0.14	3.90 ± 0.15	12.04 ± 0.18
5a	Mn-2	+1	4:3	1.5 × 10−5	2.54 ± 0.14	3.06 ± 0.32	14.16 ± 0.30
6b	Mn-2	−1	1:4	3.0 × 10−4	−2.78 ± 0.20	7.23 ± 0.07	0.22 ± 0.17
7b	Mn-3	+1	1:4	2.0 × 10−4	1.02 ± 0.22	6.27 ± 0.18	4.78 ± 0.10

^aConcentration of ionophore: 1.5 mM.

^bConcentration of ionophore: 4.0 mM.