Light‐assisted noncompetitive fluorescence immunoassay for photosensitive antibiotic detection

The development of simple, sensitive, and efficient methods for antibiotic detection is of great significance for human health and environmental protection. Currently, although the competitive immunoassays are popular for detecting antibiotic molecules, they need to label antibiotic or specific antibody with signaling molecule. The development of noncompetitive immunoassay for antibiotic detection has always faced significant challenges. Herein, we have developed a light‐assisted noncompetitive immunoassay for the detection of antibiotics based on their photosensitive characteristic. Firstly, the antibody coated on the microplate specifically captures the target antibiotic. Afterward, under light irradiation, the captured photosensitive antibiotic produces reactive oxygen species (ROS), which oxidizes the added ROS dye to generate a fluorescent signal. Therefore, a noncompetitive immunoassay for antibiotic detection is achieved by utilizing the unique property of photosensitive antibiotics to generate ROS instead of labeling signaling molecules. By using antibiotics demeclocycline hydrochloride (DMCO) and polymyxin B (PMB) as research models, the proposed noncompetitive fluorescence immunoassay can specifically detect as low as 5 ng/mL DMCO and 70 ng/mL PMB, respectively. The light‐assisted noncompetitive immunoassay strategy opens a new avenue for simple, sensitive, label‐free, and high‐throughput detection of photosensitive antibiotics or photosensitive drugs. Based on the unique photosensitive property of antibiotics, a light‐assisted noncompetitive immunoassay is developed for the detection of photosensitive antibiotics by integrating a one‐step immunoassay and the fluorescence detection of reactive oxygen species under light irradiation. The light‐assisted noncompetitive immunoassay strategy opens a new avenue for the simple, sensitive, label‐free, and high‐throughput detection of photosensitive antibiotics or photosensitive drugs.