Biofunctionalized mesoporous silica nanospheres for the ultrasensitive chemiluminescence immunoassay of tumor markers

Abstract

In this study, mesoporous silica nanospheres (MSNs) are synthesized and biofunctionalized with streptavidin for the development of an ultrasensitive chemiluminescence (CL) immunoassay. The streptavidin-functionalized MSNs have a large specific surface area and exhibit excellent hydrophilicity, which are favourable to effectively capture biotinylated antibodies and retain their bioactivity. We used α-fetoprotein (AFP) as a model analyte, which can be detected in a wide linear range of 0.01–5.0 ng mL⁻¹ with a very low detection limit down to 9 pg mL⁻¹ (S/N = 3). The assay results of clinical human serum samples using the present method are in acceptable agreement with the reference values obtained from the hospital. This biofunctionalized MSN-based CL immunoassay provides a promising approach for early screening of tumor diseases.