A Eu(III)–MOF for ratiometric fluorescence detection of ATP with a smartphone-integrated sensing platform

Background: Sensitive and selective detection of adenosine triphosphate (ATP) is essential for applications in biological analysis, clinical diagnostics, and food safety. Although luminescent probes offer high sensitivity, many systems suffer from poor stability and limited field applicability. Eu(III)-based metal–organic frameworks (MOFs) are promising due to their sharp emissions and long lifetimes; however, developing structurally robust platforms with reliable on-site sensing capability remains a significant challenge. In particular, achieving high selectivity toward ATP in complex matrices and integrating sensing systems with portable detection technologies are still underexplored. Results: Herein, a new europium-based metal–organic framework (Eu-MOF) of [Eu₂(L)₃(H₂O)₂]_n (1) (H₂L = 1,4-naphthalenedicarboxylic acid), was synthesized via a solvothermal method. The MOF 1 exhibits strong red luminescence and acts as a selective ratiometric fluorescence sensor for ATP, with a low limit of detection (LOD) of 6.61 × 10⁻⁷ M. The current results show a weak molecular interactions may be occurred between ATP and 1. Furthermore, a smartphone-integrated detection platform was developed for rapid and on-site quantification. Practical applicability was validated using real samples (deionized water, egg, and pork), yielding ATP recoveries of 92.85–108.64% with relative standard deviations (RSDs) ranging from 1.42% to 8.43%. Significance: This study presents Eu(III)-MOF-based luminescent sensor with high sensitivity and selectivity for ATP detection, coupled with a portable smartphone-assisted analytical platform. The integration of analytical performance and real-sample applicability highlights its potential for practical applications in food safety monitoring and biochemical analysis.