Abstract: A method for the in situ derivatization of at least one biogenic amine, precursor, or metabolite thereof in an isolated aqueous sample includes the steps of: (i) contacting the sample with a propionic anhydride/acetonitrile solution in the presence of a phosphate buffer having a pH in the range of 7.0 to 9.0 and allowing the conversion of amine and/or hydroxyl moieties of the biogenic amine, precursor, or metabolite thereof to form a propionyl derivative of the biogenic amine; followed by (ii) adding to the reaction mixture obtained in step (i) a carbodiimide compound and an electrophilic amine-containing compound, and allowing the carbodiimide-mediated derivatization of carboxylic acid moieties of the biogenic amine, precursor, or metabolite thereof.

Abstract: A method for the in situ derivatization of at least one biogenic amine, precursor, or metabolite thereof in an isolated aqueous sample includes the steps of: (i) contacting the sample with a propionic anhydride/acetonitrile solution in the presence of a phosphate buffer having a pH in the range of 7.0 to 9.0 and allowing the conversion of amine and/or hydroxyl moieties of the biogenic amine, precursor, or metabolite thereof to form a propionyl derivative of the biogenic amine; followed by (ii) adding to the reaction mixture obtained in step (i) a carbodiimide compound and an electrophilic amine-containing compound, and allowing the carbodiimide-mediated derivatization of carboxylic acid moieties of the biogenic amine, precursor, or metabolite thereof.

Abstract: A method for the in situ derivatization of at least one biogenic amine, precursor, or metabolite thereof in an isolated aqueous sample includes the steps of: (i) contacting the sample with a propionic anhydride/acetonitrile solution in the presence of a phosphate buffer having a pH in the range of 7.0 to 9.0 and allowing the conversion of amine and/or hydroxyl moieties of the biogenic amine, precursor, or metabolite thereof to form a propionyl derivative of the biogenic amine; followed by (ii) adding to the reaction mixture obtained in step (i) a carbodiimide compound and an electrophilic amine-containing compound, and allowing the carbodiimide-mediated derivatization of carboxylic acid moieties of the biogenic amine, precursor, or metabolite thereof.

Abstract: The invention relates to analytical chemistry, in particular to means and methods for the quantitative determination of derivatized biogenic amines, precursors or metabolites thereof. Provided is a method for the in situ derivatization of at least one biogenic amine, precursor or metabolite thereof in an isolated aqueous sample, the derivatization comprising the steps of: (i) contacting said sample with a propionic anhydride/acetonitril solution in the presence of a phosphate buffer having a pH in the range of 7.0 to 9.0 and allowing the conversion of amine and/or hydroxyl moieties of said biogenic amine or metabolite thereof to form a propionyl derivative of said biogenic amine; followed by (ii) adding to the reaction mixture obtained in step (i) a carbodiimide compound and an electrophilic amine-containing compound, and allowing the carbodiimide-mediated derivatization of carboxylic acid moieties of a biogenic amine, precursor or metabolite thereof.

Abstract: The invention relates to the field of diagnostic methods, in particular to detection of biological molecules using mass spectroscopy (MS). Provided is an automated high-throughput method for quantitating a low molecular weight protein-bound biomarker directly in an isolated biological sample, comprising the steps of: (a) automated prepurification of the sample using an effective amount of an acid protease under conditions that allow for digestion of one or more binding proteins; (b) applying said protease-digested sample onto an on-line SPE column to capture at least part of said biomarker, followed by sequential washing of the solid phase; (c) eluting a fraction comprising said biomarker directly onto a liquid chromatography (LC) column comprising an apolar stationary phase and subjecting it to LC-MS or LC-MS-MS measurements to determine the amount of at least one biomarker; and (d) quantitating the biomarker(s).