In a method for analyzing isoaspartic acid by dissociating precursor ions derived from a sample component and generating and analyzing product ions, the method includes: generating product ions by irradiating the precursor ions with hydrogen radicals or radicals having oxidizing ability to dissociate the precursor ions; separating and detecting the product ions according to a mass-to-charge ratio; and specifying product ions derived from isoaspartic acid based on a mass-to-charge ratio of the product ions.

The present disclosure provides an antibody that binds human Adhesion G Protein-Coupled Receptor B1 (BAI1) protein, compositions comprising the same, and use thereof in methods of detection, methods of diagnosis, and methods of treatment.