A "turn-off" fluorescent probe based on terbium doped Zn-MOF for sensitive detection of the food additives.

The overconsumption of food additives butylated hydroxyanisole (BHA) and acesulfame K (AK) may cause health hazards. Therefore, it is urgent to develop sensitive detection methods for them in food safety surveillance. This study reports the synthesis of terbium doped metal-organic framework material (Tb3+@Zn-MOF), which serves as the first MOF-based fluorescent probe for detecting BHA and AK, with detection limits as low as 0.42 μM (BHA) and 78 nM (AK). The detection mechanism is attributed to synergistic effect of competitive absorption (BHA) and photo induced electron transfer(AK). Furthermore, the spiked recovery experiments in actual food matrices showed that the recovery range was from 99.4% to 100.5% (BHA) and 95.56% to 101.6% (AK)，indicating good accuracy and precision. Moreover, a reliable and portable platform for rapid on-site detection of BHA was fabricated by physically incorporating Tb3+@Zn-MOF into polyvinyl alcohol (PVA) matrix.