Aggregation-induced emission-based competitive lateral flow immunoassay for rapid detection of sulfamethazine in honey

Sulfamethazine (SMZ), widely used for disease prevention of bees, is harmful to consumers when excess SMZ residues are present in honey. In this study, a novel competitive lateral flow immunoassay (LFIA) was established by using aggregation-induced emission fluorescent microsphere (AIEFM) as label for the detection of SMZ. Results indicated that the limit of detection (LOD) for the developed competitive AIEFM-LFIA in honey was 0.028 ng/mL, and the corresponding linear range was 0.05−5 ng/mL. Recovery experiments showed that the average recovery range was 75.6–95.1% with coefficient variations of 5.7–12.9% in honey. The developed competitive AIEFM-LFIA was compatible with HPLC-MS/MS in detecting SMZ in 15 real samples from honey. In general, the proposed AIEFM-LFIA is well suited for the competitive format and has great potential for the detection of other small targets with single antigenic site in practical application.