Dual Recognition Strategy for the Rapid and Precise Detection of Bacillus cereus Using Post-modified nano-MOF and Aptamer

Bacillus cereus is one of the most common foodborne pathogens and is widely distributed in foods, soil, water, plants and fodder. As an aerobic Gram-positive bacteria, B. cereus also plays an important role in liquor production, generating flavor enhancers and antibacterial substances. Therefore, a rapid and precise analysis strategy for this microbe is highly desired in food safety and sustainable food production. In this study, we propose an effective approach for B. cereus quantification using a dual recognition biosensor. B. cereus was specifically enriched with aptamer-functionalized magnetic beads, and then detected using the broad-spectrum fluorescent material, fragmented crystalline mannose-conjugated lectin-modified nano-MIL-53(Al)-NH2 (FcMBL@NM5AN). The dual recognition method was applied for specific quantification of B. cereus in the range of 20–2 × 108 CFU/mL with a limit of detection of 4 CFU/mL within 60 min. Recoveries ranged from 93.8%−100.8% in milk, rice, chicken meat, eggs, and distilled yeast as real samples were also obtained.