Incorporation of siderophore binding sites in a dipodal fluorescent sensor for Fe(III).
A new fluorescent probe 3, has been developed for the detection of Fe(III) in water based samples. The design of 3 involved the incorporation of Fe(III) binding sites observed in naturally occurring Siderophores into a synthetic sensing assembly. The probe, containing two Schiff base receptors connected to a mesitylene platform, was prepared in two steps. The dipodal sensor displayed good selectivity for Fe(III) when tested against other physiological and environmentally important metal ions, in HEPES buffered solution at pH 7.0, through a quenching of the fluorescent intensity. Stern-Volmer analysis of this quenching interaction indicated a 1:1 (host : guest) binding stoichiometry between the probe and Fe(III). The association constant, K(a) calculated using the Benesi-Hildebrand equation was found to be 3.8 x 10(4) M(-1). Crucially, the sensor was capable of measuring Fe(III) competitively in solutions containing both Fe(III) and Cu(II). Thus, the adoption of Fe(III) binding sites found in nature, into synthetic luminescent assemblies has proven an effective design strategy for the development of new Fe(III) probes.
Singh
Narinder
N
School of Pharmacy and Life Sciences, The Robert Gordon University, Aberdeen, Scotland AB10 1FR, UK.
Kaur
Navneet
N
Callan
John F
JF
D001665:Binding Sites; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D007501:Iron / Q000032:analysis*; D015394:Molecular Structure; D017262:Siderophores / Q000378:metabolism*; D012996:Solutions
D005456:Fluorescent Dyes; D017262:Siderophores; D012996:Solutions; D007501:Iron