Multifunctional Mesoporous Nanoellipsoids for Biological Bimodal Imaging and Magnetically Targeted Delivery of Anticancer Drugs

Abstract

A general polyelectrolyte‐mediated self‐assembly technique is adopted to prepare multifunctional mesoporous nanostructures as an effective biological bimodal imaging probe and magnetically targeted anticancer drug (doxorubicin) delivery systems (DDSs). A positively charged polyelectrolyte (PAH) and negatively charged fluorescent quantum dots (QDs) are successfully assembled onto the surface of ellipsoidal Fe3O4@SiO2@mSiO2 composite nanostructures to combine the merits of tunable fluorescent/magnetic properties, mesoporous nanostructures for drug loading, and the uniform ellipsoidal morphology for enhanced uptake by cancer cells. The resultant nanoellipsoids are homogeneously coated with four layers of PAH/QDs, with an additional PAH layer to make the ellipsoidal surface positively charged. This acts to enhance cellular uptake, which is driven by electrostatic interactions between the positive nanoparticle surface and the negative cell surface. The high biocompatibility of the achieved multifunctional nanoellipsoids is demonstrated by a cell‐cytotoxicity assay, hemolyticity against human red blood cells, and coagulation evaluation of fresh human blood plasma after exposure to the nanoparticles. Moreover, confocal microscopy and bio‐TEM observations show that the cell uptake of nanocarriers is dose‐dependent, and the nanoparticles accumulate mostly in the cytoplasm. The excellent capability of the nanocarriers as contrast agents for MRI is demonstrated by the relatively high r2 value (143 mM−1s−1) and preliminary in vivo characterization. More importantly, the doxorubicin‐loaded DDSs show higher cytotoxicity than the free doxorubicin drug as contributed by the intracellular release pathway of doxorubicin from the DDSs, indicating the potential application of the obtained multifunctional mesoporous nanoellipsoids as highly effective bimodal imaging probes and DDSs for cancer diagnosis and chemotherapy, simultaneously.

Silica Nanorattle–Doxorubicin-Anchored Mesenchymal Stem Cells for Tumor-Tropic Therapy

“…At 88 h, the drug release amount reached 50% at pH 4 but only 11% at pH 7.4. The pH-sensitive drug release profile is consistent with previous reports about DOX release from mesoporous silica nanomaterials, 37,38 which can be attributed to the altered interaction force strength between the silica nanoparticles and drug molecules under different pH values. The high drug loading amount is beneficial for increasing the drug concentration delivered to cancer cells and decreasing the burden of MSCs as nanoparticle vehicles.…”

Facile Fabrication of Single-Phase Multifunctional BaGdF5 Nanospheres as Drug Carriers

“…Figure a shows the field-dependent magnetization curve of BaGdF 5 at 300 and 3 K. The nanospheres are paramagnetic at 300 K and the magnetic mass susceptibility of the BaGdF 5 nanoparticles was determined to be 9.27 × 10 –5 emu·Oe –1 ·g –1 . The magnetization is 1.93 and 4.66 emu·g –1 at 20 and 50 kOe, respectively, which is similar to the reported value. − Besides, at 3 K, the nanospheres are superparamagnetic with saturation magnetization values of 140 emu·g –1 . As shown in the inset of Figure a, the nanoparticles were attracted to one side of the cuvette by a magnet at room temperature.…”

Heparinized magnetic mesoporous silica nanoparticles as multifunctional growth factor delivery carriers

“…As can be seen from table 1, the PRT of 0.6 mg ml −1 of MFMSNs-NH 2 submicron spheres did not show a clear difference compared to the blank control (0.9% NaCl). This is consistent with an earlier report, in which amino-modified ellipsoidal Fe 3 O 4 @SiO 2 @mSiO 2 composite at various concentrations has no effect on the normal blood coagulation process via the prothrombin time (PT) and activated partial thromboplastin time (APTT) assays [28]. As for MFMSNs-HP, the PRT value at a concentration of 0.2 mg ml −1 was larger than that of the blank control (977 s versus 345 s, p < 0.05).…”