The development of multifunctional nanoparticles for diagnosis and therapy of cancer has been a focus of research in recent years. Owing to excellent properties of chemophotothermal therapy and tumor targeting accompanied by magnetic resonance (MR) or computed tomography (CT) imaging, mesoporous silica has been widely applied to tumor diagnosing carriers. However, previous research focused more on chemotherapy combined with photothermal therapeutic strategies but ignored intuitive assessment of tumors. In this work, we report a novel nanoprobe consisting of hyaluronic-acid–modified Gold Nanorods@mSiO2@Mn@DOX (GNR@MMH@DOX) nanoparticles, which realize multifunctional integration of therapeutics and imaging. Au nanorods (GNRs) were synthesized without a seed precursor by a water bath method, then sequentially modified with mesoporous silica, doped with Mn²⁺, and loaded with doxorubicin in a solution. In vitro and in vivo assays verified their great biocompatibility, good stability, and attractive specificity of targeting to receptor CD44, which is overexpressed on cancer cells. In addition, GNR@MMH nanoparticles proved to be a more distinguishable CT/MR imaging contrast compared to commercial contrast agents. The article demonstrates promising composition for CT/MR imaging and photothermal therapy of tumors, giving new insights into the diagnosis and therapy of different kinds of malignant tumors.

A universal platform with Mn doping and hyaluronic acid (HA) modification, based on mesoporous silica (mSiO₂), was designed and used as a basic multifunctional material with magnetic resonance (MR) imaging. Furthermore, we added flexible functions through the addition of functional molecules. Specially, two typical compounds, hydrophobic perfluorooctyl bromide (PFOB) and hydrophilic doxorubicin (DOX), were loaded into the channels to obtain PFOB@Mn@mSiO₂@HA (PMMH) or DOX@Mn@mSiO₂@HA (DMMH) nanoparticles for dual-mode imaging or imaging and therapy, respectively. The PMMH and DMMH nanoparticles were highly targeted to the lymph system in vitro and in vivo. MR and ultrasound imaging of PMMH nanoparticles were performed in the lymph system, while MR imaging and chemotherapy of DMMH nanoparticles was used to detect cancer. These results showed that both PMMH and DMMH nanoparticles can be designed with high lymph targeting efficiency. PMMH nanoparticles are a dual-mode contrast agent for both ultrasound and MR imaging for the lymph system and DMMH nanoparticles are powerful agents for the combined diagnosis and therapy of cancer in vivo.