A new PdMOF-loaded molecularly imprinted polyaniline nanocatalytic probe for ultratrace oxytetracycline with SERS technique.

• Highly catalytic PdMOF and di-functional PdMOF@MIP probe were prepared. • The nanoprobe exhibits recognition of OTC and catalysis of HAuCl 4 -NaH 2 PO 2 to generate AuNPs. • The in situ generated AuNPs as indicator can be monitoring by SERS. • A trimode molecular spectral method for ultratrace oxytetracycline was established. • The SERS method is of simplicity, high sensitivity and selectivity. In this paper, a new Pd metal organic framework (PdMOF) surface molecularly imprinted polyaniline nanocatalytic probe (PdMOF@MIP) with dual functions of recognition and catalysis was synthesized. It is found that the PdMOF@MIP nanoprobe can not only identify OTC but also catalyze the new nanoreaction of NaH 2 PO 2 -HAuCl 4 to generate gold nanoparticles (AuNPs), and the generated AuNPs could be traced by surface-enhanced Raman scattering (SERS). When OTC specifically binds to PdMOF@MIP to generate PdMOF@MIP-OTC conjugate, its catalytic effect is weakened and the analytical signal is reduced linaerly. Accordingly, a new, highly sensitive, selective and simple SERS/RRS/Abs trimode detection platform for OTC was constructed. The linear range of SERS was 0.0625 ng/mL ∼ 1.75 ng/mL and the limit of detection was 0.015 ng/mL. This new nanocatalytic probe detection strategy can also be used for the selective detection of other antibiotics such as tetracycline and doxycycline, respectively. In addition, the nanocatalytic mechanism has been investigated. [ABSTRACT FROM AUTHOR]