Reaction conditions for the reducing-end-specific derivatization of cellulose substrates with the fluorogenic compound, anthranilic acid, have been established. Hydrolysis of fluorescence-labelled celluloses by cellobiohydrolase Cel7A from Trichoderma reesei was consistent with the active-site titration kinetics (burst kinetics), which allowed the quantification of the processivity of the enzym...

A reaction strategy involving functional group selective modification of the O-alkenyl-ether double bond within plasmenyl ether containing lipids using iodine and methanol, in conjunction with functional group selective derivatization of amine-containing lipids using a novel (13)C1-S,S'-dimethylthiobutanoylhydroxysuccinimide ester ((13)C1-DMBNHS) reagent, is shown to improve the capabilities of...

Federal Ministry of Education and Research (BMBF): Kompetenznetz Demenzen (01 GI 0420) and HBPP-NGFN2 (01 GR 0447). We gratefully appreciate the technical help of Christine Schö del. protein phosphorylated at threonine 181 in CSF as a neurochemical bi-omarker in Alzheimer's disease: original data and review of the literature. Highly conserved and disease-specific patterns of carboxyterminally t...

A cloud-point extraction (CPE) method using the surfactant (30)p-tert-octylphenol polyoxyethylene (OPEO30) was proposed as the preceding step for the determination of polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS). Given the need for surfactant derivatization before the chromatographic analysis, the reaction conditions of coacervate derivatization were s...

This work is an overview of our use of affinity capillary electrophoresis (ACE) to estimate binding constants between D-Ala-D-Ala terminus peptides and the glycopeptides vancomycin (Van) from Streptomyces orientalis, teicoplanin (Teic) from Actinoplanes teicomyceticus, and ristocetin A (Rist) from Nocardia lurida. In these studies, modifications in the ACE technique, including partial-filling A...

A method for the quantitation of proteinaceous selenocysteine (SeCys) in Se-rich yeast was developed. The method is based on the reduction of the Se-Se and S-Se bridges with dithiotretiol, derivatization with iodoacetamide (carbamidomethylation), followed by HPLC-ICP MS. The chromatographic conditions were optimized for the total recovery of the proteinaceous selenocysteine, the minimum number ...

Recently, considerable progress has been made in designing biomaterial surfaces which possess enhanced albumin affinity. Two derivatization methods for producing albumin binding biomaterial surfaces, based on an albumin affinity dye, cibacron blue, have been developed. Both surface derivatization methods were found to enhance the binding of albumin to an implant grade polyetherurethane. Evaluat...

The use of a supercritical carbon dioxide reaction medium for the determination of the (R)- and (S)-enantiomers of mandelic acid (MA) is proposed. The process involves a previous derivatization step under supercritical conditions by which the carboxyl group is esterified with methanol, then followed by acylation of the hydroxyl group in methyl MA with pentafluoropropionic anhydride in the absen...

A method for sequence analysis and identification of phosphoamino acids in peptides based on high performance liquid chromatography (HPLC) is described. The peptides were derivatized with an Edman type reagent, 4-(1'-cyanoisoindolyl)phenylisothiocyanate (CIPIC) and subsequently cleaved to generate stable and fluorescent 4-(1'-cyanoisoindolyl)phenylthiazolinone (CIP-TZ)-amino acids. Several expe...

We describe preparation and use of the quaternary ammonium-based α-iodoacetamide QDE and its isotopologue *QDE as reagents for chemoselective derivatization of cellular thiols. Direct addition of the reagents to live cells followed by adduct extraction into n-butanol and analysis by FT-ICR-MS provided a registry of matched isotope peaks from which molecular formulae of thiol metabolites were de...