Highly Effective Drug Delivery and Cell Imaging Using Fluorescent Double-Imprinted Nanoparticles by Targeting Recognition of the Epitope of Membrane Protein.

Nanocarriers with both targeting ability and stable loading of drugs can more effectively deliver drugs to precise tumor sites for therapeutic effects. Accordingly, we have rationally designed fluorescent molecularly imprinted polymer nanoparticles (FMIPs), which use N-terminal epitope of P32 membrane protein as the primary template and doxorubicin (DOX) as the secondary template. The DOX imprinted cavity can stably carry the drug and the epitope-imprinted cavity allows FMIPs to actively recognize the P32-positive 4T1 cancer cells. The targeted therapeutic effect of DOX-loaded FMIPs (FMIPs@DOX) is investigated in vitro and in vivo. The FMIPs@DOX only causes apoptosis in 4T1 cancer cells compared to C8161 cells (expressing low level of P32). In addition, highly effective inhibition of 4T1 malignant breast tumors using FMIPs@DOX is achieved in the model of tumor-bearing mice. Importantly, the antitumor effect achieved by intravenous injection of FMIPs@DOX is almost identical to that by intratumoral injection. Furthermore, the FMIPs can serve as a targeted fluorescence imaging agent due to the high specificity of the epitope-imprinted cavity and the stable fluorescence of the embedded silicon nanoparticles. These results demonstrate the effectiveness of the FMIPs for active targeted drug delivery and imaging. Furthermore, the FMIPs provide a direction for drug-loaded nanocarrier.