Facile colorimetric detection of human chorionic gonadotropin based on the peptide-induced aggregation of gold nanoparticles

摘要

The human chorionic gonadotropin (hCG) assay for ectopic pregnancy is typically conducted using an enzyme immunoassay (EIA); however, EIA is complicated and time-consuming. Herein, we developed a simple, rapid and sensitive colorimetric assay for hCG based on the anti-aggregation of unmodified gold nanoparticles (AuNPs). The introduction of positively charged hCG-specific peptides into an AuNP solution causes the aggregation of the AuNPs, resulting in a color change from red to blue. When hCG is present, peptide/hCG complexes are formed, thus inhibiting the peptide-induced AuNP aggregation. The dynamic range for hCG detection ranged from 50 to 1000 mIU mL?1, with a detection limit of 25 mIU mL?1. Additionally, this colorimetric sensor was successfully evaluated with serum samples spiked with hCG, demonstrating its ability to be used for the onsite monitoring of hCG...