Synthesis, characterisation and ion-binding properties of oxathiacrown ethers appended to [Ru(bpy)]. Selectivity towards Hg, Cd and Pb.

A series of complexes with oxathiacrown ethers appended to a [Ru(bpy)] moiety have been synthesized and characterised using H NMR, C NMR, IR, electronic absorption and emission spectroscopies, mass spectrometry and elemental analyses. The complexes exhibit strong MLCT luminescence bands in the range 608-611 nm and one reversible metal centred oxidation potential in the range 1.00-1.

Toxigenic potential of Aspergillus species occurring on maize kernels from two agro-ecological zones in Kenya.

Two agro-ecological zones in Kenya were selected to compare the distribution in maize of Aspergillus spp. and their toxigenicity. These were Nandi County, which is the main maize growing region in the country but where no human aflatoxicoses have been reported, and Makueni County where most of the aflatoxicosis cases have occurred.