A novel N-heterocyclic AIEgen for highly selective ATP sensing and visual bacterial detection in beverages

The rapid and accurate detection of adenosine 5′-triphosphate (ATP) is crucial for clinical diagnostics, bioanalysis, and food safety. This study presents two novel aggregation-induced emission (AIE)-active probes, BIP-PP-1 and BIP-PP-2 , derived from a new N-heterocyclic AIEgen core, benzo[4,5]imidazo[1,2- c ]pyrimidine (BIP). The optimized probe, BIP-PP-2 , functions as a high-performance ATP sensor with a large Stokes shift, high sensitivity (LOD = 0.85 μM, linear range 0 – 90 μM), and excellent selectivity over structurally similar anions such as ADP, AMP, CTP, TTP, and UTP, a feature seldom achieved in small-molecule ATP probes. This unique selectivity is attributed to the novel BIP core, where specific π-π stacking and hydrogen-bonding interactions with the adenine moiety of ATP provide a superior stereoelectronic match, driving precise recognition and AIE-based fluorescence enhancement via a synergistic combination of electrostatic and non-covalent forces. BIP-PP-2 was successfully applied in real-time ATP imaging within live bacterial cells and, notably, in the rapid visual detection of bacterial contamination in beverages using a portable 365 nm UV lamp, achieving a visual detection limit of 3.9 × 10 5  CFU mL −1 under ambient light. This work introduces the BIP scaffold as a promising platform for functional dye design and establishes BIP-PP-2 as a robust analytical tool for on-site bioanalysis and food safety monitoring. © 2001 Elsevier Science. All rights reserved.