In-situ preparation of the membrane modified with Ag nanoparticles@metal-organic frameworks material and its application in rapid sample loading and surface enhanced Raman scattering detection

In this study, a new method for preparing surface enhanced Raman scattering detection material based on membrane was proposed. First, Zeolitic imidazolate framework-67 was modified on a polypropylene membrane by in-situ growth. Subsequently, Ag nanoparticles were modified on the membrane by in-situ synthesis. After characterization by scanning electron microscopy, energy dispersive spectrometer, infrared spectrometer, x-ray diffractometer, x-ray photoelectron spectrometer and so on, it could be proved that Zeolitic imidazolate framework-67 and Ag nanoparticles were successfully modified on the surface of polypropylene membrane. The polypropylene membrane modified with Ag nanoparticles@Zeolitic imidazolate framework-67 prepared by the in-situ method has the advantages of good uniformity and stability of Zeolitic imidazolate framework-67 and Ag nanoparticles. Based on the polypropylene membrane modified with Ag nanoparticles@Zeolitic imidazolate framework-67, sample loading and surface enhanced Raman scattering detection of methylene blue could be completed within 3 min. As a result, the analysis time, on-line, real-time and practicality of surface enhanced Raman scattering detection was improved. In the analysis of real samples, compared with the polypropylene membrane modified with Ag nanoparticles@methyl-sulfur functionalized Zeolitic imidazolate framework-67 prepared by the covalent method, the polypropylene membrane modified with Ag nanoparticles@Zeolitic imidazolate framework-67 prepared by the in-situ method also showed better surface enhanced Raman scattering detection performance.