Nanoparticle-DNA-polymer composites for hepatocellular carcinoma cell labeling, sensing, and magnetic resonance imaging.

This paper describes comparative studies and protocols in (1) self-assembling of ultrasmall superparamagnetic iron oxide nanoparticle (NP), circular plasmid DNA, and branched polyethylenimine (PEI) composites; (2) magnetofection; (3) gene delivery, (4) magnetic resonance imaging (MRI), and (5) cytotoxicity of the composites toward hepatocellular carcinoma HepG2 cells.

In vivo chemoembolization and magnetic resonance imaging of liver tumors by using iron oxide nanoshell/doxorubicin/poly(vinyl alcohol) hybrid composites.

A hybrid composite made up of superparamagnetic iron oxide nanoshells encapsulating the anticancer drug doxorubicin and bound together by poly(vinyl alcohol) was developed. Transcatheter arterial delivery in an in vivo liver tumor model led to embolization of the liver tumor blood vessels. Embolization was followed by disassembly of the composite. The nanoshells were then able to pass through the leaky tumor vasculature into the tumor tissue, thereby leading to slow and sustained release of the drug. As well as being relatively noncytotoxic, the composite was responsive to magnetic resonance imaging, thus making it a potentially useful theranostic agent.

Characterization of cold atmospheric plasma-modified dentin collagen.

The aim of this study was to evaluate the crosslinking effect of the radio-frequency atmospheric-pressure glow discharge (RF-APGD) plasma jet treatment on dentin collagen. The dentin collagen was treated by an RF-APGD plasma jet with the gas temperature of 4°C under different treatment times, while the control was a non-treatment group. The dentin collagen was characterized in terms of atomic force microscopy-based nanoindentation, differential scanning calorimeter, Raman analysis and X-ray photoelectron spectroscopy (XPS) measurement. The crosslinking effect of the plasma-treated dentin collagen was found compared to that of the control group. The elastic modulus and denaturation temperature of the dentin collagen after plasma treatment for 30 s were significantly higher than those in the control group (p<0.05). The RF-APGD plasma jet treatment can promote the crosslinking of the dentin collagen, which is of great significance to improve its mechanical and thermal stabilities.

Effects of a helium cold atmospheric plasma on bonding to artificial caries-affected dentin.

This study investigated the effects of a helium cold atmospheric plasma (CAP) on the bonding performance and surface modification of the caries-affected dentin (CAD). Artificial CAD was created by pH-cycling. The microtensile bond of CAD were examined before and after CAP treatments at 24 h and after 2-year aging. The effects of surface modification were studied with contact-angle measurement, scanning electron microscopy and X-ray photoemission spectroscopy. Thirty-second CAP treatment increased the immediate bond strength of CAD to a level that was statistically the same as sound dentin, and slowed the aging process of the bonding as well. The CAP treatment induced modified CAD surface with increased wettability, cleaner appearance, and increased percentage of the mineral-associated elements and oxygen. This research demonstrated that the helium CAP jet treatments of 30 s and 45 s improved the bond strength of the artificial CAD, and was considerably effective in its surface modification.

Effects of cold atmospheric plasma treatment on resin bonding to high-translucency zirconia ceramics.

This study aims to evaluate the effects of cold atmospheric plasma (CAP) treatment on the bonding of resin cement to high-translucency zirconia. Zirconia specimens were subjected to different treatments: no treatment (ZrT), 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer (ZrT-M), alumina particle air-abrasion with/without MDP-containing primer (ZrT-AM/ZrT-A), CAP with/without MDP-containing primer (ZrT-PM/ZrT-P). The surface topography, wettability, and chemical composition were evaluated. The shear bond strength (SBS) was tested before and after thermocycling. CAP did not alter the morphology, increased the wettability, and decreased the carbon/oxygen ratio of zirconia surface. The SBSs of ZrT-PM and ZrT-P were significantly higher than the other groups. After thermocycling, ZrT-A, ZrT-M, ZrT-AM, and ZrT-P showed comparable SBSs, all of which were lower than ZrT-PM. It was concluded that CAP improved the bonding performance of high-translucency zirconia without damaging its surface. The combination of CAP with MDP further enhanced the bond strength and may enable durable bonding.

Effects of a modified cold atmospheric plasma jet treatment on resin-dentin bonding.

The radio-frequency atmospheric-pressure glow discharge (RF-APGD) plasma is a novel cold atmospheric plasma (CAP) source, which has low energy characteristic. This study investigated the effect of RF-APGD plasma on the mechanical properties of dentin collagen and resin-dentin bonding. The scanning electron microscopy analysis was performed before and after a novel RF-APGD plasma and a conventional CAP treatment and a tensile test was carried out for the stiffness of dentin collagen. The microtensile resin-dentin bond strength was tested either immediately or after a 50,000-cycle thermocycling process. Dentin collagen maintained an intact structure after a 45-s RF-APGD plasma treatment, whereas even a 10-s treatment with the conventional CAP collapsed the collagen scaffold. When compared with control groups, the RF-APGD plasma treatment showed: (i) an improved stiffness of dentin collagen; (ii) a significant improvement in the bonding strength before/after artificial aging. Thus, RF-APGD plasma treatment has excellent prospects as a resin-dentin bonding protocol.

Porous Pt Nanoparticles with High Near-Infrared Photothermal Conversion Efficiencies for Photothermal Therapy.

Plasmonic nanostructures are of potential in acting as a type of optical agents for cancer photothermal therapy. To effectively function as photothermal therapy agents, plasmonic nanostructures are strongly desired to have good biocompatibility and high photothermal conversion efficiencies. In this study, poly(diallyldimethylammonium chloride)-coated porous Pt nanoparticles are synthesized for photothermal therapy. The Pt nanoparticles possess broadband near-infrared light absorption in the range from 650 to 1200 nm, therefore allowing for selecting different laser wavelengths for photothermal therapy. The as-prepared Pt nanoparticles exhibit remarkable photothermal conversion efficiencies under 809 and 980 nm laser irradiation. In vitro studies indicate that the Pt nanoparticles display good biocompatibility and high cellular uptake efficiencies through an endocytosis pathway. Photothermal heating using 808 nm laser irradiation (>7.0 W cm-2 , 3 min) leads to notable cytotoxic effect, and more than 70% of cells are photothermally ablated after 3 min irradiation at 8.4 W cm-2 . Furthermore, simultaneous application of photothermal therapy synergistically enhances the cytotoxicity of an anti-cancer drug doxorubicin. Therefore, the porous Pt nanoparticles have great potential as an attractive photothermal agent for cancer therapy.

Cellular uptake behaviour, photothermal therapy performance, and cytotoxicity of gold nanorods with various coatings.

With the development of Au nanorods for a number of biomedical applications, understanding their cellular responses has become increasingly important. In this study, we systematically evaluated the cellular uptake behaviour and cytotoxicity of Au nanorods with various surface coatings, including organic cetyltrimethylammonium bromide (CTAB), poly(sodium 4-styrenesulfonate) (PSS), and poly(ethylene glycol) (PEG), and inorganic mesoporous silica (mSiO2), dense silica (dSiO2), and titanium dioxide (TiO2). The cellular behaviour of Au nanorods was found to be highly dependent on both the surface coating and the cell type. CTAB-, PSS-, and mSiO2-coated Au nanorods exhibit notable cytotoxicity, while PEG-, dSiO2-, and TiO2-coated Au nanorods do not induce cell injury. Optical imaging studies indicated that the cell type plays a preferential role in Au nanorod cellular uptake. Higher cellular uptake of Au nanorods was seen in U-87 MG, PC-3, MDA-MB-231, and RAW 264.7 cells, as opposed to HepG2 and HT-29 cells. In addition, Au nanorod cellular uptake is also highly affected by serum protein binding to the surface coating. mSiO2-, dSiO2-, and TiO2-coated Au nanorods show significantly higher cellular uptake than PSS- and PEG-coated ones, which results in a better photothermal ablation effect for Au nanorods with the inorganic surface coatings. Our study provides valuable insights into the effects of the surface modification on the biocompatibility, cellular uptake, as well as biomedical functions of Au nanorods.

Enhanced cellular uptake and gene delivery of glioblastoma with deferoxamine-coated nanoparticle/plasmid DNA/branched polyethylenimine composites.

Ternary composite nanomaterials based on deferoxamine-coated superparamagnetic iron oxide nanoparticles (8-10 nm), circular plasmid DNA (~4 kb) with fluorescent/luminescent reporter group, and branched polyethylenimine (25 kDa, PDI = 2.5) were prepared and compared in terms of their efficiencies in transfecting brain tumor cells at low concentration.