Feedstock/pretreatment screening for bioconversion of sugar and lignin streams via deacetylated disc-refining.

Recent publications have shown the benefits of deacetylation disc-refining (DDR) as a pretreatment process to deconstruct biomass into sugars and lignin residues. Major advantages of DDR pretreatment over steam and dilute acid pretreatment are the removal of acetyl and lignin during deacetylation. DDR does not generate hydroxymethylfurfural (HMF) and furfural which are commonly produced from steam and dilute acid pretreatments.

Characterization data of palladium-alumina on activated biochar catalyst for hydrogenolysis reactions.

This article presents experimental data on the techniques used for the characterization of Pd-AlO supported on activated biochar (2Pd-5Al/ABC) catalyst. The reported data is collected as a part of the research on the 2Pd-5Al/ABC catalyst used for lignin hydrogenolysis [1]. The data on X-ray powder diffraction, ammonia-temperature programmed desorption, pyridine diffuse reflectance infrared Fourier transform spectroscopy, and high-resolution scanning electron microscopy of various catalysts are valuable to study the changes in surface morphology and acidity upon metal loading.

Development of a carbon clad core-shell silica for high speed two-dimensional liquid chromatography.

We recently introduced a new method to deposit carbon on fully porous silicas (5 μm) to address some of the shortcomings of carbon clad zirconia (C/ZrO(2)), which has rather low retention due to its low surface area (20-30 m(2)/g). The method enables the introduction of a thin, homogeneous layer of Al(III) on silica to serve as catalytic sites for carbon deposition without damaging the silica's native pore structure. Subsequent carbon deposition by chemical vapor deposition resulted in chromatographically useful carbon phases as shown by good efficiencies and higher retentivity relative to C/ZrO(2).

New method for development of carbon clad silica phases for liquid chromatography: Part I. Preparation of carbon phases.

Owing to its combination of unique selectivity and mechanical strength, commercial carbon clad zirconia (C/ZrO₂) has been widely used for many applications, including fast two-dimensional liquid chromatography (2DLC). However, the low surface area available (only 20-30 m²/g for commercial porous ZrO₂) limits its retentivity. We have recently addressed this limitation by developing a carbon phase coated on the high surface area of HPLC grade alumina (C/Al₂O₃).

Preparation and evaluation of carbon coated alumina as a high surface area packing material for high performance liquid chromatography.

The retention of polar compounds, the separation of structural isomers and thermal stability make carbonaceous materials very attractive stationary phases for liquid chromatography (LC). Carbon clad zirconia (C/ZrO(2)), one of the most interesting, exhibits unparalleled chemical and thermal stability, but its characteristically low surface area (20-30 m(2)/g) limits broader application as a second dimension separation in two-dimensional liquid chromatography (2DLC) where high retentivity and therefore high stationary phase surface area are required. In this work, we used a high surface area commercial HPLC alumina (153 m(2)/g) as a support material to develop a carbon phase by chemical vapor deposition (CVD) at elevated temperature using hexane vapor as the carbon source.

Application of silica-based hyper-crosslinked sulfonate-modified reversed stationary phases for separating highly hydrophilic basic compounds.

The separation and determination of hydrophilic basic compounds are of great importance in many fields including clinical and biological research, pharmaceutical development and forensic analysis. However, the most widely used analytical separation technique in these disciplines, reversed-phase liquid chromatography (RPLC), usually does not provide sufficient retention for several important classes of highly hydrophilic basic compounds including catecholamines, many drug metabolites and many drugs of abuse. Commonly eluents having little or no organic modifier and/or strong ion pairing agents must be used to achieve sufficient retention and separation.

Fast gradient elution reversed-phase high-performance liquid chromatography with diode-array detection as a high-throughput screening method for drugs of abuse. I. Chromatographic conditions.

A new approach for the high-throughput screening of biological samples to detect the presence of regulated intoxicants has been developed by modifying a conventional gradient elution high-performance liquid chromatograph (HPLC). The goal of this work was to improve the speed of gradient elution screening methods over current approaches by optimizing the operational parameters of both the column and the instrument without compromising the reproducibility of the retention times, which is the basis for the identification of intoxicant compounds. Most importantly, the novel instrument configuration substantially reduces the time needed to re-equilibrate the column between consecutive gradient runs, thereby reducing the total time for each analysis.

Fast gradient elution reversed-phase liquid chromatography with diode-array detection as a high-throughput screening method for drugs of abuse. II. Data analysis.

In Part I of this work, we developed a method for the detection of drugs of abuse in biological samples based on fast gradient elution liquid-chromatography coupled with diode array spectroscopic detection (LC-DAD). In this part of the work, we apply the chemometric method of target factor analysis (TFA) to the chromatograms. This algorithm identifies the target compounds present in chromatograms based on a spectral library, resolves nearly co-eluting components, and differentiates between drugs with similar spectra.