(260l) Adsorption Mechanisms of Palladium (II) Trichloro-Hydroxy Complex on the Tobacco Mosaic Virus Surface

Biotemplating has been successfully employed in nanomaterials synthesis and has been proven to be an

efficient means of nanomaterial production. Particularly, templated synthesis, using Tobacco Mosaic

Virus (TMV), has produced high quality nanorods and nanowires that found applications in catalysis,

memory devices and batteries. Although biotemplating, using TMV and its mutants, has been

successfully demonstrated, there is a lack of fundamental understanding of governing molecular

mechanisms and processes that happen on the surface of the virus. In this study, the adsorption of the

dominant palladium(II) ion (PdCl3H2O)- on TMV Wild type, TMV1Cys and TMV2Cys was investigated

using UV-Vis spectroscopy. As a result, adsorption on TMV Wild type and TMV1Cys was found to be

successfully modeled by Langmuir isotherm while adsorption on TMV2Cys was modeled by Freundlich

isotherm. Using these models, we were able to estimate the maximum adsorption capacities of the

viruses and address the thiol group(s) effects on the mechanism of adsorption of the dominant ion. The

effect of chlorine ion concentration on adsorption equilibrium on TMV1Cys was also investigated since it

was evident from previous studies that ionic strength of the solution had significant effects on chloro-

palladate ion adsorption. The adsorption of the chloro-palladate ions on the TMV surface was inversely

proportion to total chloride concentration at low palladium ion equilibrium concentrations. Conversely,

the loading of chloro-palladate ions on the TMV increased with increasing total chloride concentrations

at high palladium ion equilibrium concentrations. This analysis allowed us to get further insight into the

molecular mechanism of palladium (II) adsorption on TMV surface and opened new opportunities for

future establishment of a more fundamental understanding of the processes behind TMV templated

biomineralization.