Nitrite (NO(2)(-)) and formaldehyde (FA) are practice common food hazards, seriously threatening human health. Herein, for the first time a de novo nanoprobe, named MTB, with a single response group exhibiting different optical signals for NO(2)(-)/FA was reported, which had the following characteristics: i) An adamantane-labeled small molecule NI-adH grafted with polycyclodextrin (Poly-β-CD) to form MTB with excellent water-solubility and biocompatibility. ii) O-phenylenediamine (OPD) with photoinduced electron transfer (PET) played both a fl...