Fabricating polydopamine-coated Mo[Se.sub.2]-wrapped hollow mesoporous silica nanoplatform for controlled drug release and chemo-photothermal therapy

Background: Integration of several types of therapeutic agents into one nanoplatform to enhance treatment efficacy is being more widely used for cancer therapy. Methods: Herein, a biocompatible polydopamine (PDA)-coated Mo[Se.sub.2]-wrapped doxorubicin (DOX)-loaded hollow mesoporous silica nanoparticles (HMSNs) nanoplatform (PM@HMSNs-DOX) was fabricated for dual-sensitive drug release and chemo-photothermal therapy for enhancing the therapeutic effects on breast cancer. The HMSNs were obtained by a "structural difference-based selective etching" strategy and served as the drug carrier, exhibiting a high DOX loading capacity of 427 mg/g HMSNs-N[H.sub.2], and then wrapped with PDA-coated Mo[Se.sub.2] layer to form PM@HMSNs-DOX. Various techniques proved the successful fabrication of the nanocomposites. Results: The formed PM@HMSNs-DOX nanocomposites exhibited good biocompatibility, good stability, and super-additive photothermal conversion efficiency due to the cooperation of Mo[Se.sub.2] and PDA. Simultaneously, the pH/near-infrared-responsive drug release profile was observed, which could enhance the synergistic therapeutic anticancer effect. The antitumor effects of PM@HMSNs-DOX were evaluated both in vitro and in vivo, demonstrating that the synergistic therapeutic efficacy was significantly superior to any monotherapy. Also, in vivo pharmacokinetics studies showed that PM@HMSNs-DOX had a much longer circulation time than free DOX. In addition, in vitro and in vivo toxicity studies certified that PM@HMSNs are suitable as biocompatible agents. Conclusion: Our nanoplatform loaded with DOX displays pH/near-infrared-induced chemotherapy and excellent photothermal therapy, which hold great potential for cancer treatment. Keywords: hollow mesoporous silica nanoparticles, Mo[Se.sub.2], polydopamine, chemo-photothermal therapy