Kinetic Determination of Lanthanum(III) by the Catalytic Effect on the Oxidation of Fluorescent Safranine Dyes with Potassium Bromate.

Two simple and sensitive kinetic-fluorometric methods have been developed for the determination of lanthanum(III): fluorescence quenching generated by the oxidation of safranine T or phenosafranine with potassium bromate in an acetate buffer solution. The rate of the oxidation reaction is significantly accelerated after adding lanthanum(III). A good linearity between the relative fluorescence intensity and lanthanum(III) is observed in the range of both 0.

An electrochemical sensor for simultaneous determination of ascorbic acid, dopamine, uric acid and tryptophan based on MWNTs bridged mesocellular graphene foam nanocomposite.

A multi-walled carbon nanotubes (MWNTs) bridged mesocellular graphene foam (MGF) nanocomposite (MWNTs/MGF) modified glassy carbon electrode was fabricated and successfully used for simultaneous determination of ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (TRP). Comparing with pure MGF, MWNTs or MWNTs/GS (graphene sheets), MWNTs/MGF displayed higher catalytic activity and selectivity toward the oxidation of AA, DA, UA and TRP. Under the optimal conditions, MWCNs/MGF/GCE can simultaneously detect AA, DA, UA and TRP with high selectivity and sensitivity.

Electrochemical detection of scDNA cleavage in the presence of macrocyclic hexaaza-copper(II) complex.

The hexaaza macrocyclic copper(II) complex Cu(II)L(L=1,8-Dihydroxyethyl-1,3,6,8,10,13-hexaazacyclotetradecane), which has octahedral structure similar to some natural complexes, is synthesized and purified. In this study, oxidative breakage DNA by the reaction of Cu(II)L with H2O2 and ascorbate has been investigated by gel electrophoresis experiments. In electrochemical experiments, the on scDNA-modified glassy carbon electrode(GCE) is cleaved by the Cu(II)L and redox changing of the metal catalyst without adding any other reagents.

Chlorobis[N-ethoxycarbonyl-N'-(p-methoxyphenyl)thiourea-kappaS]copper(I).

The title copper(I) complex, [CuCl(C(11)H(14)N(2)O(3)S)(2)], was synthesized by the redox reaction of cupric chloride with the corresponding thiourea derivative as reducing agent. The Cu(I) coordination environment is trigonal planar, involving two S atoms and one Cl atom. The presence of intramolecular hydrogen bonds leads to the formation of a cis conformation and promotes the stability of the complex.