Mercury selective electrodes using dimethylsulphoxide carrier

Mercury [II] ion-selective PVC membrane sensor based on dimethylsulphoxide [DMSO] as a novel oxygen and sulfur containing sensing material was successfully developed. This reagent has the advantage of low cost and simple chemical material. Dioctylphthalate [DOP] solvent could be selected from different solvents used. DOP was found to play an important role in directing selectivity. A sodium tetraphenylborate [NaTPB] as a lipophilic salt and KCI solution of 10[-1] M as an inner solution also have been chosen. The sensor exhibited a good linear response of 30 +/- 0.2 mV per decade within the concentration range 10[-8] - 10[-2] and detection limit 0.9 x 10[-8] mol 1[-1] Hg [II]. Also, it showed good selectivity and fast response for mercury [II] ion with relation to some alkali, alkaline earth, transition and heavy metal ions. DMSO-based sensor was suitable for aqueous solutions of pH range 1.5 to 4.0. Moreover, it can be used for three months without any considerable divergence in potential. The formation constant of ionophore complex with Hg [II] ion was calculated by using segmented sandwich membrane method. The proposed sensor was applied as an indicator electrode for potentiometric titration of Hg [II] ion with EDTA solution, as well as with I[-], OH[-] and IO3[-] ions. In addition, the solubility products for the previous ions were determined

Iron [III] chelates of some schiff bases derived from isatin and chromone with some amino acids and hydrazine derivatives

Iron [III] complexes of the Schiff bases derived from isatin or chromone with glycine, beta-alanine, anthranilic acid, s- methylhydrazine carbodithioate, ammonium salt of hydrazine carbodithioate, thiosemicarbazide, semicarbazide and benzoyl hydrazine were prepared and characterized by elemental analysis, IR, UV vis. spectra and magnetic measurements. Octahedral structures have been assigned to the prepared complexes