Both Fe3 + and Fe2 + ions occur in FeCl3-doped polyacetylene. At low dopant levels ( < 0.01 mole frac­ tion) both Fe2 + and Fe3 + io'ns are paramagnetic down to 4.2 K. At dopant levels > 0.01 mole fraction, there is evidence from Mossbauer spectroscopy that Fe2+ ions associate into aggregates which are magneti­ cally ordered below 25 K. Aggregate formation appears to correlate with high electri...

A novel luminescent Zn(2+) ions chemosensor, a cyclometalated platinum(II) bipyridyl acetylide complex, was designed. Of particular significance is that it shows a high sensitivity towards Zn(2+) ions without interference from other biologically important cations in acetonitrile. The tautomerization of amide favors detecting Zn(2+) ions among other HTM (heavy and transition metal) ions in aqueo...

A new pyrene derivative (1) containing a diaminomaleonitrile moiety exhibits high selectivity for Cu2þ detection. Significant fluorescence enhancement was observed with chemosensor 1 in the presence of Cu2þ. However, the metal ions Agþ, Ca2þ, Cd2þ, Co2þ, Fe2þ, Fe3þ, Hg2þ, Mg2þ, Mn2þ, Ni2þ, Pb2þ, and Zn2þ produced only minor changes in fluorescence values for the system. The apparent association...

[reaction: see text] The development of an ion-selective chemosensor for Cd(2+) allows generation of a "real-time" sensor. Immobilization of the chemosensor on quartz was achieved in a simple monolayer and in a thin film using a polymer intermediary. As intended, the thin film contains much more chemosensor than the monolayer and provides measurable responses to aqueous Cd(2+) concentrations be...

A selective, simple and low-cost method for the colorimetric determination of Fe3+ ions based on chitosan capped silver nanoparticles (Chit-AgNPs) was presented. Chitosan is a cationic polyelectrolyte and possesses amino and hydroxy groups which make it widely used as a capping agent for Ag NPs. The synthesized chitosan capped silver nanoparticles with excellent colloidal stability were charact...

A naphthalimide appended rhodamine based fluorescent chemosensor '1' is synthesized which undergoes through bond energy transfer in the presence of Hg(2+) ions in mixed aqueous media.

In this study, highly ordered mesoporous silica material (SBA-15) functionalized with Diethyl 2 - (9 -fluorenyl) malonate as a flourophore is reported. The anchoring of flourophores to the hydroxyl group on SBA-15 surface was done with post synthesis method. The obtained materials were characterized by small and wide angle X-ray diffraction, N2 adsorption–desorption, Fourier transform infrared ...

A highly sensitive and simple colorimetric assay for the detection of Fe3+ ions was developed using gold nanoparticles (AuNPs) conjugated with glycol chitosan (GC). The Fe3+ ion coordinates with the oxygen atoms of GC in a hexadentate manner (O-Fe3+-O), decreasing the interparticle distance and inducing aggregation. Time-of-flight secondary ion mass spectrometry showed that the bound Fe3+ was c...