Thyroglobulin quantitation by mass spectroscopy

摘要

Provided are methods for determining the amount of thyroglobulin in a sample using various purification steps followed by mass spectrometry. The methods generally involve purifying thyroglobulin in a test sample, digesting thyroglobulin to form peptide T129, purifying peptide T129, ionizing peptide T129, detecting the amount of peptide T129 ion generated, and relating the amount of peptide T129 ion to the amount of thyroglobulin originally present in the sample.

主权项

1. A method of determining the amount of thyroglobulin in a test sample, comprising:
(a) digesting thyroglobulin (Tg) in the test sample; (b) enriching a digested Tg peptides comprising an amino acid sequence VIFDANAPVAVR (SEQ ID NO:1); (c) ionizing the Tg peptide and an isotopically labeled internal standard, wherein the internal standard comprises a synthetic winged peptide comprising an amino acid sequence VIFDANAPVAVR (SEQ ID NO:1) that is digested with thyroglobulin from the test sample; and (d) quantifying the amount of the Tg peptide ion from step (c) by mass spectrometry; wherein the amount of the Tg peptide ion detected in step (d) is related to the amount of thyroglobulin in said test sample.