Anion-exchange Chromatographic Separation Research Articles

A Walker 256 tumor-induced osteogenic small animal model for the evaluation of [ 99 mTc] diphosphonate radiopharmaceuticals

A mammalian model has been developed for the in vivo evaluation of bone imaging agents. The model is based upon the quantification of a discrete, initial secondary periosteal osteogenesis induced in cortical bone immediately adjacent to an intramuscularly implanted Walker 256 tumor in Fisher 344 rats. Evaluation of the model consists of a histopathological examination of the periosteal bone formation, biodistribution studies on 99 m Tc-MDP and 99 m Tc-HMDP commercial kit preparations, and biodistribution studies on two 99 m Tc-HEDP component fractions isolated after anion exchange chromatographic separations from an investigative “carrier added” preparation. Reversed phase HPLC separations of the 99 m Tc-MDP and 99 m Tc-HMDP commercial kit preparations illustrate distinct differences in chemical composition between the two bone agents.

Methods for the analysis of inorganic anions : IV. Reversed-phase high-performance liquid chromatography with aqueous hydrophobic ion pairs as eluents

Inorganic anions can be well resolved on a reversed-phase C 18 chromatographic column by using a dilute aqueous solution of tetrabutylammonium salicylate as eluent. The retention behaviour of six anions (H 2PO − 4, Cl −, Br −, NO − 3, I − and SO 2− 4) on this column was investigated. The retention is sensitive to pH changes of the eluent which probably forms a double layer on the stationary phase, permitting a dynamic anion-exchange chromatographic separation. This efficient and simple method has been applied to the quantitation of the anion contents of fruit juices.

Anion-exchange chromatographic separation of Bi and Sb from As, Sn and other elements in malonic acid solution

Anion-exchange chromatographic studies of bismuth(III) and antimony(III) in malonate solution have been carried out. Bi(III) forms anionic malonate complexes at pH4.5–6, whereas Sb(III) forms them at pH5.5–6. Such complexes were sorbed on a Dowex-21K column and HCl, H2SO4, HNO3, HClO4 and chlorides, nitrates and sulphates of sodium and ammonium were tested as eluants, their efficiencies being evaluated in terms of elution constants (E) and volume distribution coefficients (Dv). Methods have been developed for the separation of Bi(III) and Sb(III) from a large number of elements by exploiting the differences in complexing power of these elements. The sequential separation of As(III), Sb(III), Bi(III) and Sn(IV) was the important feature of the work.

Anion-exchange chromatographic separation of phosphorus oxo-anions

Anion-exchange chromatographic separation of phosphorus oxo-anions

Anion-exchange chromatographic separation of linear phosphates with eluent containing a chelating agent

Anion-exchange chromatographic separation of linear phosphates with eluent containing a chelating agent

The pH Dependence of Anion Exchange Chromatographic Separation of Tri- and Tetraphosphate Anions

Abstract The anion-exchange distribution ratios of tri-, tetra-, and pentaphosphate were determined in a Dowex 1-X4-potassium chloride system at different pH by the batch method. The difference between the mean charges of the phosphates in resin phase and solution was explained in terms of a higher pH of resin phase than that of the solution. pH dependence of the separation factors for tri- and tetraphosphate and for tetra- and pentaphosphate was estimated from the batch equilibrium data, and the relative elution positions of these phosphates were confirmed by the practical chromatographic runs.