Surface-enhanced Raman Scattering Technology Based on WO3 Film for Detection of VEGF

W ith the advancement of nanomaterials for surface-enhanced Raman scattering(SERS) detection, a deeper understanding of the chemical mechanism(CM) and further applications has been achieved. Herein, we prepared a porous tungsten trioxide(WO 3 ) film by the pulse electrodeposition method, and constructed a WO 3 film SERS aptasensor. With methylene blue(MB) as the adsorption molecule, the developed WO 3 film SERS aptasensor revealed remarkable Raman activity. Through experimental data and theoretical calculations, we found that the significant SERS enhancement[enhancement factor(EF)=1.5× 10 6 ] was due to the CM based on charge transfer and molecular resonance. Utilizing the Raman response of MB on the WO 3 film and specific aptamers, we successfully developed the aptamer sensor by covalently attaching the MB modified aptamer to the WO 3 film. The sensor realized the specific and sensitive determination of vascular endothelial growth factor(VEGF) with the detection limit down to 8.7 pg/mL. In addition, the developed aptasensor indicated the excellent selectivity among other interferences, such as metal ions, reactive oxygen species(ROS), and proteins. This WO 3 film SERS aptasensor not only contributed to the study of the enhancement mechanism of semiconductor material, but also provided a powerful platform for the sensitive detection of VEGF, possessing a great potential in the real-time monitoring of biomarkers of glioblastoma in vitro .