Study of Reagent Adsorption Kinetics Dynamics Using Surface Plasmon Resonance Spectroscopy

Specific reagent adsorption is the basis of many applications in industries such as microelectronics, mineral processing, cosmetics and personal care. Though considerable work has been done to understand the role of physico-chemical parameters of reagents and their adsorption, much less has been done to understand the kinetic aspects. In many processes the rate of the adsorption of the reagent is very important, for example in understanding the effects of various species on flotation behavior.
In our work we investigated the use of surface plasmon resonance spectroscopy (SPR) to study the dynamics of reagent adsorption on precious metals and their alloys on a short time scale (milliseconds).


From SPR analysis it was observed that reagents with different functional groups have distinctively different binding rates. The rate of deposition of each reagent was calculated from theoretical considerations to obtain the adsorption density of reagent as a function of time. The limiting slope of this adsorption density vs. time graph at almost zero time was used as a tool to compare the relative rates of adsorption. A quantitative ranking was given to reagent adsorption kinetics based on the comparison of these limiting slopes. Such information will help the understanding of the real-life dynamic situations in flotation operation.


Extent of deposition of reagents on gold using SPR