To investigate the internalization ability and efficiency of mPEG × HER2-modified PLD to HER2+-overexpressed ovarian cancer cells, we modified mPEG × HER2 or mPEG × DNS to Lipo-DiD, which is a mPEGylated nanoparticle that can exert red fluorescent signals after excitation, and tracked the fluorescent signals after incubating with HER2+ SKOV-3 cells for different time periods (1, 6 and 12 h) by flow cytometry and live cell imaging system. The gene discussed is ERBB2; the disease is ovarian cancer.