A desire to achieve one-pot syntheses of value-added products from biomass sugars has led to intense research efforts to convert these sugars with high yields into their ketose forms. Aldose-to-ketose isomerization has an unfavorable equilibrium, and to date, high yield conversion to ketoses in a manner that allows for further conversion economically has yet to be demonstrated. Here, a novel strategy for simultaneous-isomerization and reactive-extraction (SIRE), where the isomerization of aldose sugars and the reactive-extraction of ketoses occur concurrently in the same vessel, is presented. In SIRE, the unfavorable aldose-ketose equilibrium is overcome by selective extraction of ketose from the reaction medium maintained at the optimal pH of the xylose-glucose isomerase (XI) enzyme; the ketose sugar is back-extracted into a low pH strip solution as a pure, concentrated sugar stream. Starting with pure xylose and using Gensweet ® for isomerization, best results for xylulose concentration and purification were achieved with an extraction phase of 1-octanol containing naphthalene-2-boronic acid (N2B) and Aliquat ® 336. SIRE, followed by a two-stage strip, resulted in a nearly pure xylulose stream at high concentration and yield. Sugar can be concentrated in both the extraction and stripping steps by reducing the volume ratio of the sugar-receiving phase relative to the sugar-donating phase for each step. This result is significant as the separation of isomers is regarded as one of the most challenging and high cost purification processes. When implemented with biomass hydrolyzates, this technology has the potential to provide contaminant-free, concentrated ketose sugar streams without the need for energy-intensive separation and concentration schemes.

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Three-dimensional, voxel-based, and wavelength-dependent skin lesion models are developed and simulated using Monte Carlo techniques. The optical geometry of the Nevoscope with trans-illumination is used in the simulations for characterizing the lesion thickness. Based on the correlation analysis between the lesion thickness and the diffuse reflectance, optical wavelengths are selected for multispectral imaging of skin lesions using the Nevoscope. Tissue optical properties reported by various researchers are compiled together to form a voxel library. Tissue models used in the simulations are developed using the voxel library which offers flexibility in updating the optical properties and adding new media types into the models independent of the Monte Carlo simulation code.

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