2D Zn-MOF fluorescence probe for detecting D-tyrosine in methanol or aqueous systems

The nature of amino acids as the building blocks of proteins leading to detection and identification is a current hot topic. Therefore, {[Zn 3 (L − ) 2 (HBTC 2− ) 2 ]·2H 2 O·CH 3 CN} n ( Zn-1 , H 3 BTC = 1,3,5-benzenetricarboxylic acid, HL = 6-aminonicotinic acid, CH 3 CN = acetonitrile), a 2D Zn-MOF which can sensitively detect and selectively recognize D -tyrosine was synthesized by solvothermal method . Identification of D -tyrosine was determined by increasing fluorescence intensity and red-shifting of the emission wavelength . Zn-1 is highly stable in methanol (MeOH) and aqueous solution (H 2 O), so it was dissolved in them as fluorescence probes, namely Zn-1/MeOH probe and Zn-1/H 2 O probe , respectively. The two probes worked for lower limits of detection, 8.93 × 10 −2 μM for Zn-1/MeOH probe and 79.70 × 10 −2 μM for Zn-1/H 2 O probe . The Stern-Volmer quenching constant of Zn-1/MeOH probe is 1.28 × 10 4 M −1 and of Zn-1/H 2 O probe is 4.55 × 10 2 M −1 . In addition, the two probes still show excellent immunity to interference under the interference of 18 amino acids. Zn-1/H 2 O probe was also applied to the determination of D -tyrosine in real milk samples with good results. This study provides a fast, simple, convenient and relatively accurate method for detecting D -tyrosine.