Practical Protocol for Making Calibration Curves for Direct and Sensitive Quantitative LC Orbitrap-MS of Large Neuropeptides.

ABSTRACT: Peptides larger than 3-4 kDa, such as neuropeptide Y (NPY), orexin-B, and alpha-MSH, have practical issues that arise when conducting direct and sensitive quantitative liquid chromatography (LC) orbitrap-FT mass spectrometry (MS) due to their adsorption and low ionization efficiency, especially in standard solutions. A mixing solvent consisting of 0.5% trifluoroacetic acid (TFA) and 35-50% aq. acetonitrile was developed as the standard NPY for creating calibration curves, as well as a matrix to block the experimental tube surface to minimize adsorption. The mixture matrix effectively blocked non-specific adsorption of the standard peptides with tryptic digested bovine serum albumin (BSA) (small fragment peptides) and orexin-B (a large chain peptide). A sample containing 1 : 100 peptide:wat

SUBMITTER: Yamagaki T 

PROVIDER: S-EPMC7392841 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature