Immunochromatographic Assay of Hepatitis B Surface Antigen Using Magnetic Nanoparticles as Signal Materials

An immunochromatographic assay for the detection of hepatitis B surface antigen (HBsAg) was developed using Fe
₃
O
₄
nanoparticles as signal materials. Anti-HBsAg antibodies were labeled with carboxylated Fe
₃
O
₄
particles with an average diameter of 153.6 nm, and an immunochromatography strip was constructed. The detection capability of the assay developed here is 1 ng/mL HBsAg.