Publications by authors named "R Ohmacht"

The preparation of the so-called bonded phase liquid chromatographic packings is usually carried out by heating the silica, the silane, a catalyst, or a scavenger in an appropriate solvent (often toluene.) Due to the longtime of boiling, the procedure is time and energy consuming, and solvent intensive. The goal of this work is to present a simple, environment-friendly preparation method with reduced solvent consumption to synthetize RP liquid chromatographic stationary phases.

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During the polymerization of actin, hydrolysis of bound ATP occurs in two consecutive steps: chemical cleavage of the high-energy nucleotide and slow release of the γ-phosphate. In this study the effect of phalloidin and jasplakinolide on the kinetics of P(i) release was monitored during the formation of actin filaments. An enzyme-linked assay based spectrophotometric technique was used to follow the liberation of inorganic phosphate.

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Neutral steroid hormones are currently analyzed by gas or liquid chromatography/mass spectrometry based methods. Most of the steroid compounds, however, lack volatility and do not contain polar groups, which results in inadequate chromatographic behavior and low ionization efficiency. Derivatization of the steroids to form more volatile, thermostable, and charged products solves this difficulty, but the derivatization of compounds with unknown chemical moieties is not an easy task.

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Amadori peptides were enriched using boronate affinity tips and measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS). As demonstrated by electrochemical measurements, the tips show the highest binding efficiency for glucose at pH 8.2 employing ammonium chloride/ammonia buffer with ionic strength of 150 mM, exceeding taurine buffer at the same concentration.

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SPE plays a crucial role in bioanalytical research. In the present work a novel fullerene(C60)-derivatised silica material is compared with octadecyl(C18) - and triaconthyl(C30)-silicas regarding recoveries of peptides and sequence coverage of HSA and fibrinogen digests. C30- and C60(30 nm)-SPE materials were found to be the two most prominent SPE materials.

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