125results about "Isotope introduction to peptides/proteins" patented technology

Methods for introducing fluorine atom onto a polypeptide are provided. Also provided are linkers, bioconjugates, and bifunctional compound agents made using the methods, linkers, and bioconjugates. The methods comprise: (i) providing a linker comprising a thiol-reactive terminus and an aldehyde-reactive terminus; (ii) reacting the thiol-reactive terminus of the linker with a polypeptide comprising at least one thiol group or a reactive derivative thereof; and (iii) subsequently reacting the aldehyde-reactive terminus of the linker with a fluorine-substituted aldehyde.

F-18 radiolabeled peptides are prepared by reacting a peptide comprising a hydroxylamine, a thiosemicarbazide, a hydrazine or a free amine group with 4-[18F]Fluorobenzaldehyde. Specific, non-limiting examples of F-18 radiolabeled peptides are described herein. The labeled peptides are useful, for example, in clinical positron emission tomography.

Relative quantification of metabolites by Electrospray Ionization Mass Spectrometry (ESI-MS) requiring a mechanism for simultaneous analysis of multiple analytes in two or more samples. Labeling reagents that are reactive to particular compound classes and differ only in their isotopic kit facilitating relative quantification and providing tangible evidence for the existence of specific functional groups. Heavy and light isotopic forms of methylacetimidate were synthesized and used as labeling reagents for quantification of amine-containing molecules, such as biological samples. Heavy and light isotopic forms of formaldehyde and cholamine were also synthesized and used independently as labeling reagents for quantification of amine-containing and carboxylic acid-containing molecules, such as found in biological samples. Advantageously, the labeled end-products are positively charged under normal acidic conditions involving conventional Liquid Chromatography Mass Spectrometry (LC / MS) applications. Labeled primary and secondary amine and carboxylic acid end-products also generated higher signals concerning mass-spectra than pre-cursor molecules and improved sensitivity. Improved accuracy concerning relative quantification was achieved by mixing heavy and light labeled Arabidopsis extracts in different ratios. Labeling strategy was further employed to ascertain differences in the amounts of amine-containing metabolites for two strains of Arabidopsis seeds.

The invention relates to conjugates of formula (V) or (VI), their use as radiopharmaceuticals, processes for their preparation, and synthetic intermediates used in such processes.

The invention relates to conjugates of formula (V) or (VI): wherein X is —CO—NH—, —NH—, —O—, —NHCONH—, or —NHCSNH—; their use as radiopharmaceuticals, processes for their preparation, and synthetic intermediates used in such processes.