Plasma surface resonation-high performance liquid chromatography-mass spectrometry (SPR-HPLC-MS) technology was proposed by betterways Company in Guangzhou, China in 2018. By immobilizing small molecule drugs on SPR chip as stationary phase and using cell lysates as mobile phase, the potential target proteins of small molecules on cells can be obtained. By using this technique, the potential target proteins of citral on Staphylococcus aureus were obtained, which provided a basis for the subsequent study of the mechanism of target effects (such as stimulation or inhibition). One subproject is included in this project.