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ABSTRACT:The objective of this study was to investigate the possibility of using maize tassel as an alternative adsorbent for the removal of chromium (VI) and cadmium (II) ions from aqueous solutions. The effect of pH, solution temperature, contact time, initial metal ion concentration and adsorbent dose on the adsorption of chromium (VI) and cadmium (II) by tassel was investigated using batch methods. Adsorption for both chromium (VI) and cadmium (II) was found to be highly pH dependent compared to the other parameters investigated. Obtained results gave an adsorption capacity of 79.1 % for chromium (VI) at pH 2, exposure time of 1h at 25 ºC. Maximum capacity of cadmium of 88 % was obtained in the pH range of 5-6 at 25 ºC after exposure time of 1 h. The adsorption capacities of tassel for both chromium (VI) and cadmium (II) were found to be comparable to those of other commercial adsorbents currently in use for the removal of heavy metals from aqueous wastes. These results have demonstrated the immense potential of maize tassel as an alternative adsorbent for toxic metal ions remediation in polluted water and wastewater.

Heparin, a naturally occuring, polydisperse, polyanionic glycosaminoglycan, was investigated as a chiral selector for capillary zone electrophoresis. Baseline separations were obtained for a variety of underivatized drugs including antimalarials and antihistamines. Analysis was carried out at a pH of 4.5 or 5 using 2% heparin (w/w) in a 10 mM phosphate buffer under an applied voltage of 15 kV. All of the solutes successfully resolved contained at least two nitrogens with one of the nitrogens incorporated in a heterocyclic aromatic ring. Further, successful enantioresolution seemed to require that the nitrogens be somewhat distant from each other in the molecule. The results suggest that, in addition to electrostatic interactions, solute size may also play a role in the heparin chiral recognition mechanism.

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