Renewable Resources Robert-Jan van Putten,†,‡ Jan C. van der Waal,† Ed de Jong,*,† Carolus B. Rasrendra,‡,⊥ Hero J. Heeres,*,‡ and Johannes G. de Vries* †Avantium Chemicals, Zekeringstraat 29, 1014 BV Amsterdam, the Netherlands ‡Department of Chemical Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands DSM Innovative Synthesis BV, P.O. Box 18, 6160 MD Geleen, the Netherlands Department of Chemical Engineering, Institut Teknologi Bandung, Ganesha 10, Bandung 40132, Indonesia

Hydroxymethylfurfural, A Versatile Platform Chemical Made from Renewable Resources

5-Hydroxymethylfurfural (HMF) as a building block platform: Biological properties, synthesis and synthetic applications

Some Typical Advances in the Synthetic Applications of Allenes

Separation of polar compounds on polar stationary phases with partly aqueous eluents is by no means a new separation mode in LC. The first HPLC applications were published more than 30 years ago, and were for a long time mostly confined to carbohydrate analysis. In the early 1990s new phases started to emerge, and the practice was given a name, hydrophilic interaction chromatography (HILIC). Although the use of this separation mode has been relatively limited, we have seen a sudden increase in popularity over the last few years, promoted by the need to analyze polar compounds in increasingly complex mixtures. Another reason for the increase in popularity is the widespread use of MS coupled to LC. The partly aqueous eluents high in ACN with a limited need of adding salt is almost ideal for ESI. The applications now encompass most categories of polar compounds, charged as well as uncharged, although HILIC is particularly well suited for solutes lacking charge where coulombic interactions cannot be used to mediate retention. The review attempts to summarize the ongoing discussion on the separation mechanism and gives an overview of the stationary phases used and the applications addressed with this separation mode in LC.

Hydrophilic interaction chromatography.

Hydrophilic interaction liquid chromatography (HILIC) provides an alternative approach to effectively separate small polar compounds on polar stationary phases. The purpose of this work was to review the options for the characterization of HILIC stationary phases and their applications for separations of polar compounds in complex matrices. The characteristics of the hydrophilic stationary phase may affect and in some cases limit the choices of mobile phase composition, ion strength or buffer pH value available, since mechanisms other than hydrophilic partitioning could potentially occur. Enhancing our understanding of retention behavior in HILIC increases the scope of possible applications of liquid chromatography. One interesting option may also be to use HILIC in orthogonal and/or two-dimensional separations. Bioapplications of HILIC systems are also presented.

/pdf/hydrophilic-interaction-liquid-chromatography-hilic-a-6908wnnc4y.pdf

Hydrophilic interaction liquid chromatography (HILIC)—a powerful separation technique

A method based on column switching packed capillary liquid chromatography electrospray mass spectrometry has been developed for the determination of the adduct glyoxal–deoxyguanosine, a biomarker candidate for the assessment of glyoxal exposure, in DNA hydrolysate solutions. Microgram amounts of DNA were isolated and enzymatically hydrolyzed to deoxyribonucleosides, prior to ultrafiltration and subsequent dilution to a sample solution consisting of water–acetonitrile–formic acid (98 : 2 : 0.2, v/v). The sample solution was loaded onto a 1 mm I.D. × 5 mm Hypercarb (5 μm) porous graphitic carbon trap column for analyte enrichment using an injection volume of 200 μl, and was subsequently back-flushed onto a 0.30 mm I.D. × 150 mm Lichrospher diol (5 μm) analytical column. The samples were loaded with a flow rate of 40 μl min−1 and glyoxal–deoxyguanosine was desorbed from the trap column and eluted with an isocratic mobile phase consisting of water–acetonitrile–formic acid (50 : 50 : 0.2, v/v) at a flow rate of 5 μl min−1. Mass spectrometric determination of glyoxal–deoxyguanosine was obtained by multiple reaction monitoring of the transition [M + H]+m/z 326 → m/z 210. The method was evaluated over the concentration range 0.25–50 ng ml−1 of glyoxal–deoxyguanosine in the hydrolysate of 5 μg DNA. The method was linear with a correlation coefficient of 0.9998 in this range. The within-day (n = 6) and between-day (n = 6) precisions were determined as 1.2–11% and 1.4–11% RSD, respectively, and the recovery was close to 100%. The mass limit of detection was 15 pg, corresponding to a concentration limit of detection of 75 fg μl−1 DNA hydrolysate solution, corresponding to 48 adducts per 106 normal nucleosides. The method was applied for the determination of glyoxal–deoxyguanosine in DNA hydrolysate solutions of calf thymus DNA and cell cultures after reaction or incubation with glyoxal.

Sensitive determination of a glyoxal–DNA adduct biomarker candidate by column switching capillary liquid chromatography electrospray ionization mass spectrometry

The effect of make-up gas was studied for capillary gas chromatography (GC) coupled with on-column atomic emission spectrometric detection (AED), where a 350 kHz plasma was sustained inside the end of a 0.32 mm i.d. capillary GC column. For selective detection of Cl and Br both the plasma background characteristics and elemental responses were stabilized during temperature programmed analysis when 10–15 ml min–1 of helium were added as a make-up gas. In addition, chromatographic peaks were protected against tailing, while Cl and Br were detected at the 4 pg s–1 level.

Effect of make-up gas in on-column atomic emission spectrometric detection for capillary gas chromatography

Capillary gas chromatography coupled with microplasma mass spectrometry for organotin speciation.

High-performance liquid chromatographic separation and determination of prostaglandins, oxidized by pyridinium dichromate : Optimization and applications

Capillary gas chromatography (GC) combined with on-column radio frequency plasma atomic emission detection was evaluated for the determination of polychlorinated and polybrominated biphenyls (PCBs and PBBs). Quantitation was possible utilizing a single chlorine or bromine calibration curve based on a randomly selected reference compound, because the signal per ng of halogen ranged within 17 % for 29 congeners. Combined with an internal standard to correct for potential plasma quenching from matrix components, this type of universal quantitation represented a sub-stantial simplification of current calibration procedures. In combi-nation with relatively low detection limits (1–5 pg/s of halogen), the present work suggested that GC, coupled with on-column atomic emission detection is a promising technique for the determination of halogenated micropollutants.

Determination of chlorinated and brominated micropollutants by capillary gas chromatography coupled with on‐column radio frequency plasma atomic emission detection

Tyge Greibrokk

Papers

Sensitive determination of a glyoxal–DNA adduct biomarker candidate by column switching capillary liquid chromatography electrospray ionization mass spectrometry

Effect of make-up gas in on-column atomic emission spectrometric detection for capillary gas chromatography

Capillary gas chromatography coupled with microplasma mass spectrometry for organotin speciation.

High-performance liquid chromatographic separation and determination of prostaglandins, oxidized by pyridinium dichromate : Optimization and applications

Determination of chlorinated and brominated micropollutants by capillary gas chromatography coupled with on‐column radio frequency plasma atomic emission detection