Folate-Conjugated Cell Membrane Mimetic Polymer Micelles for Tumor-Cell-Targeted Delivery of Doxorubicin

Tumor-targeting nano-drug-delivery systems hold great potential to improve the therapeutic efficacy and alleviate the side effects of cancer treatments. Herein, folic acid (FA)-decorated amphiphilic copolymer of FA-P(MPC- co-MaPCL) (MPC: 2-methacryloxoethyl phosphorylcholine, MaPCL: poly(ε-caprolactone) macromonomer) is synthesized and its micelles are fabricated for doxorubicin (DOX) delivery. And non-FA-decorated P(MPC- co-MaPCL) micelles are used as the control. Dynamic light scattering and scanning electron microscopy measurements reveal that FA-P(MPC- co-MaPCL) and P(MPC- co-MaPCL) micelles are spherical with average diameters of 140 and 90 nm, respectively. The evaluation in vitro demonstrates that the blank micelles are nontoxic, while DOX-loaded FA-P(MPC- co-MaPCL) micelles show significant cytotoxicity to HeLa cells and slight cytotoxicity to L929 cells. Moreover, the cellular uptake of DOX-loaded FA-P(MPC- co-MaPCL) micelles in HeLa cells are 4.3-fold and 1.7-fold higher than that of DOX-loaded P(MPC- co-MaPCL) micelles and free DOX after 6 h of incubation, respectively. These results indicate the great potential of this system in anticancer target drug-delivery applications.

Visible light driven mesoporous Ag-embedded ZnO nanocomposites: reactive oxygen species enhanced photocatalysis, bacterial inhibition and photodynamic therapy

The systemic diagram shows the mechanism of photocatalysis, bacterial inhibition and photodynamic therapy through the generation of reactive oxygen species.

Spectral fractionation detection of gold nanorod contrast agents using optical coherence tomography

We demonstrate the proof of concept of a novel Fourier-domain optical coherence tomography contrast mechanism using gold nanorod contrast agents and a spectral fractionation processing technique. The methodology detects the spectral shift of the backscattered light from the nanorods by comparing the ratio between the short and long wavelength halves of the optical coherence tomography signal intensity. Spectral fractionation further divides the halves into sub-bands to improve spectral contrast and suppress speckle noise. Herein, we show that this technique can detect gold nanorods in intralipid tissue phantoms. Furthermore, cellular labeling by gold nanorods was demonstrated using retinal pigment epithelial cells in vitro.

Self-assemblied nanocomplexes based on biomimetic amphiphilic chitosan derivatives for protein delivery

A bio-inspired nanocarrier was developed for protein delivery based on biodegradable amphiphilic chitosan derivative (DCA-PCCs) with hydrophilic cell membrane mimic phosphorylcholine (PC) and hydrophobic deoxycholic acid (DCA) moieties, which was synthesized via the combination of Atherton-Todd reaction and carbodiimide coupling reaction. Using bovine serum albumin (BSA) as model protein, it was found that DCA-PCCs with suitable degree of substitution of PC and DCA moieties can load proteins by forming nanocomplexes via a solvent evaporation method. The physicochemical characteristics of BSA/DCA-PCCs nanocomplexes were investigated by Zetasizer, atomic force microscopy (AFM) and Fourier-transform infrared (FT-IR) spectroscopy. In vitro biological evaluation revealed BSA/DCA-PCCs nanocomplexes as blank DCA-PCCs nanoparticles had excellent cytocompatibility and hemocompatibility mainly due to the presence of cell membrane mimic phosphorylcholine. BSA release results suggested BSA/DCA-PCCs nanocomplexes showed a sustained release behavior following first order exponential decay kinetics. The results indicated DCA-PCCs provided a promising approach for effectively delivering therapeutic proteins.

In vitro drug release and biological evaluation of biomimetic polymeric micelles self-assembled from amphiphilic deoxycholic acid-phosphorylcholine-chitosan conjugate

Novel biomimetic amphiphilic chitosan derivative, deoxycholic acid-phosphorylcholine-chitosan conjugate (DCA-PCCs) was synthesized based on the combination of Atherton-Todd reaction for coupling phosphorylcholine (PC) and carbodiimide coupling reaction for linking deoxycholic acid (DCA) to chitosan. The chemical structure of DCA-PCCs was characterized by (1)H and (31)P nuclear magnetic resonance (NMR). The self-assembly of DCA-PCCs in water was analyzed by fluorescence measurements, dynamic laser light-scattering (DLS), zeta potential and transmission electron microscopy (TEM) technologies. The results confirmed that the amphiphilic DCA-PCCs can self-assemble to form nanosized spherical micelles with biomimetic PC shell. In vitro biological evaluation revealed that DCA-PCCs micelles had low toxicity against NIH/3T3 mouse embryonic fibroblasts as well as good hemocompatibility. Using quercetin as a hydrophobic model drug, drug loading and release study suggested that biomimetic DCA-PCCs micelles could be used as a promising nanocarrier avoiding unfavorable biological response for hydrophobic drug delivery applications.

Toxicity of nano molybdenum trioxide toward invasive breast cancer cells

Current chemotherapy is limited by the nature of invasive cancer cells, which are similar to cancer stem cells. Nanomaterials provide a potential alternate mode of cancer therapy. This study investigated the cytotoxicity of molybdenum trioxide (MoO3) nanoplates toward invasive breast cancer iMCF-7 cells by analyzing morphological changes and performing Western blot and flow cytometry analyses. The findings suggested that MoO3 exposure induces apoptosis and generates reactive oxygen species (ROS) in iMCF-7 cells. This study revealed the potential utility of MoO3 for treating metastatic cancer cells, which might enable advancements in cancer therapy.