Enzyme-linked immunosorbent assay for detection of chitooligosaccharides

In order to detect chitooligosaccharides (COS), an enzyme-linked immunosorb ent assay (ELISA) was developed. A chitooligosaccharide mixture (COSM) conj ugated to bovine serum albumin was used to immunize rabbits to produce an a nti-COS polyclonal antibody. By use of specific antibody and COSM-horseradi sh peroxidase conjugate, we established a competitive direct ELISA (cdELISA ) the detection limit of which was about 0.1 mu g/ml. In the cdELISA, the c ross-reactivities of the specific antibody toward glucosamine, chitobiose, chitotriose, chitotetraose, chitopentaose, and chitohexaose were 0.27, 27, 75, 75, 144, and 100%, respectively, and those toward N-acetylchitobiose, N -acetylchitotriose, N-acetylchitotetraose, N-acetylchitopentaose, and N-ace tylchitohexaose were 1.58, 0.005, 1.08, 0.05, and 0.40%, respectively.