Fluorescence of Mg-Al-Eu ternary layered double hydroxide sensitivity to phenylalanine

We reported for the first time the fluorescence sensitivity of a Mg-Al-Eu ternary layered double hydroxide (LDH) to phenylalanine (Phe). As shown in fluorescent spectra, the red emissions resulted from (5)D(0)-(7)F(J) transition (J=1, 2) of Eu(3+) were quenched by Phe, and a strong peak around at 492 nm emerged. A strong interaction between the Mg-Al-Eu LDH and Phe was manifested by markedly different chemical shift positions of the Mg 2p, Al 2p, Eu 4d, O 1 s, and C 1 s peaks in the XPS spectra from those of the LDHs. These results showed that the charges transfer from Phe to the trivalent Eu ions may be taken place.