Jm. Price et al., POLYMER-SUPPORTED PH SENSORS BASED ON HYDROPHOBICALLY BOUND LUMINESCENT RUTHENIUM(II) COMPLEXES, Analytical chemistry, 70(2), 1998, pp. 265-270
A new luminescence intensity-based sensor-polymer support system is de
scribed. The pH-sensitive element is [Ru(phen)(2)[phen(OH)(2)]](2+) or
[Ru(Ph(2)phen)(2)[phen(OH)(2)]](2+) (phen = 1,10-phenanthroline, Ph(2
)phen = 4,7-diphenyl-1,10-phenanthroline, and phen(OH)(2) = 4,7-dihydr
oxy-1,10-phenanthroline) immobilized on a polymer built from a four-fu
nction cyclic methyl siloxane ring polymer having (SiRCH3O)(4) units w
ith poly(ethylene oxide) cross-linkers. Hydrophobic binding of the sen
sor to the polymer is used to avoid the need for covalent chemistry. T
hese sensor systems have a usable sensitivity over the 2-8 pH range, b
ut are most usable in the 2-6 pH range. Response times for thick films
(250 mu M) are rapid (several minutes).