We hypothesize that the bioavailability of adsorbed organic contaminants is determined by their conformation upon adsorption and that this conformation is affected by the chemical properties of the surface and the contaminant. Research will quantify the surface chemistry effects on adsorption conformation and the subsequent availability of adsorbed contaminants for bacterial degradation.
We will determine the degradation kinetics for model compounds separately and as mixtures in suspended pure and mixed bacterial cultures. Biofilm formation kinetics for pure and defiined mixed cultures, cultivated on a benign substrate will be determined. Silicon crystals of known texture will serve as control surfaces.
Next we will use self assembled monolayers (SAMs) to bind desired functional groups to silicon sub strata; thus controlling local surface chemistry at constant topography. Variation in surface chemistry of each substratum will be determined by a regimen of surface analyses.
Single organic contaminants, then mixtures of those contaminants will be exposed to the various sub strata. Contaminant configuration will vary due to the pre-treatment chemistry or the spatial variation in that treatment. Contaminant conformations will be quantified using the techniques above.
Rates of bacterial cell adhesion and bio~im formation will be measured non-invasively using ~uorescent confocal microscopic image analysis. Degradation of adsorbed contarninants will be monitored using ~uorescent reporter genes. Rates of contaminant degradation, alone or within a mixture, will be correlated to the molecular configuration adsorbed to the surface.