title: Quantitation of Insulin-Like Growth Factor 1 in Serum by Liquid Chromatography High Resolution Accurate-Mass Mass Spectrometry.
abstract: Insulin-like growth factor 1 (IGF-1) is a 70 amino acid peptide hormone which acts as the principal mediator of the effects of growth hormone (GH). Due to a wide variability in circulating concentration of GH, IGF-1 quantitation is the first step in the diagnosis of GH excess or deficiency. Majority (>95 %) of IGF-1 circulates as a ternary complex along with its principle binding protein insulin-like growth factor 1 binding protein 3 (IGFBP-3) and acid labile subunit. The assay design approach for IGF-1 quantitation has to include a step to dissociate IGF-1 from its ternary complex. Several commercial assays employ a buffer containing acidified ethanol to achieve this. Despite several modifications, commercially available immunoassays have been shown to have challenges with interference from IGFBP-3. Additionally, inter-method comparison between IGF-1 immunoassays has been shown to be suboptimal. Mass spectrometry has been utilized for quantitation of IGF-1. In this chapter a liquid chromatography high resolution accurate-mass mass spectrometry (LC-HRAMS) based method for IGF-1 quantitation has been described.
authors.affiliation: Departement of Pathology, University of Michigan Health System, Ann Arbor, MN, 48109-5054, USA.
authors.forename: Hemamalini
authors.initials: H
authors.lastname: Ketha
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 2nd Street SW, Rochester, MN, 55905, USA. Singh.Ravinder@mayo.edu.
authors.forename: Ravinder J
authors.initials: RJ
authors.lastname: Singh
mesh_terms: D053000:Analytic Sample Preparation Methods; D001774:Blood Chemical Analysis / Q000379:methods*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000302:isolation & purification; D013058:Mass Spectrometry / Q000379:methods*; D052616:Solid Phase Extraction
chemical_list: D007334:Insulin-Like Growth Factor I
keywords: High resolution mass spectrometry; Insulin -like growth factor-1 quantitation; Protein quantitation using mass spectrometry