Online immunoaffinity assay-CE using magnetic nanobeads for the determination of anti-Helicobacter pylori IgG in human serum

Abstract

About two-thirds of the world's population is infected with Helicobacter pylori (H. pylori). This Gram-negative bacterium is the most important etiological agent of chronic active type B gastritis and peptic ulcer diseases. Conventional methods such as gastric biopsy, ELISA and culture, require a long time for the determination of H. pylori infections. Moreover, the antibodies in human serum sample are capable to react immunologically with the purified H. pylori antigens immobilized on different kinds of support like magnetic nanobeads. In this study, we have developed an online immunoaffinity assay-CE to determine the concentration of anti-H. pylori IgG using magnetic nanobeads as a support of the immunological affinity ligands and an LIF as a detector. The separation was performed in 0.1 M glycine-HCl, pH 2, as the background electrolyte. The linear calibration curve to predict the concentration of H. pylori-specific immunoglobulin G antibodies in serum was produced within the range of 0.12-100 U/mL. The linear regression equation was i=492.86+96.03×Canti-H. pylori, with the linear regression coefficient r2=0.999. The LOD calculated by fluorescence detection procedure was of 0.06 U/mL. The whole assay was done in no more than 35 min and it was entirely automatized. The development of immunoaffinity assay-CE in this study demonstrates that there is a large possibility to introduce nanotechnology in several fields with significant advantages over the classic methodologies. Our proposition comprises the diagnosis and screening field.