Yuebin Li

Copper sulfide nanoparticles for photothermal ablation of tumor cells

AIMS Copper sulfide (CuS) nanoparticles were developed as a new type of agent for photothermal ablation of cancer cells. MATERIALS & METHODS CuS nanoparticles were synthesized by wet chemistry and their application in photothermal ablation of tumor cells was tested by irradiation using a near-infrared (NIR) laser beam at 808 nm to elevate the temperature of aqueous solutions of CuS nanoparticles as a function of exposure time and nanoparticle concentration. CuS nanoparticle-mediated photothermal destruction was evaluated using human cervical cancer HeLa cells with respect to laser dose and nanoparticle concentration. Their toxicity was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS CuS nanoparticles have an optical absorption band in the NIR range with a maximum absorbance at 900 nm. Irradiation by a NIR laser beam at 808 nm resulted in an increase in the temperature of the CuS nanoparticle aqueous solution as a function of exposure time and nanoparticle concentration. CuS nanoparticle-induced photothermal destruction of HeLa cells occured in a laser dose- and nanoparticle concentration-dependent manner, and displayed minimal cytotoxic effects with a profile similar to that of gold nanoparticles. CONCLUSION Owing to their unique optical property, small size, low cost of production and low cytotoxicity, CuS nanoparticles are promising new nanomaterials for cancer photothermal ablation therapy.

Recent Development of Sandwich Assay Based on the Nanobiotechnologies for Proteins, Nucleic Acids, Small Molecules, and Ions

Nanobiotechnologies for Proteins, Nucleic Acids, Small Molecules, and Ions Juwen Shen, Yuebin Li,†,§,⊥ Haoshuang Gu, Fan Xia,*,† and Xiaolei Zuo*,‡ †Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China ‡Division of Physical Biology and Bioimaging Center, Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201800, China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Physical and Electronic Sciences, Hubei University, Wuhan 430062, China Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China

Nanoceria have no genotoxic effect on human lens epithelial cells

There are no treatments for reversing or halting cataract, a disease of the structural proteins in the eye lens, that has associations with other age-related degenerative conditions such as Alzheimers disease. The incidence of cataract and associated conditions is increasing as the average age of the population rises. Protein folding diseases are difficult to assess in vivo as proteins and their age-related changes are assessed after extraction. Nanotechnology can be used to investigate protein changes in the intact lens as well as for a potential means of drug delivery. Nanoparticles, such as cerium oxide (CeO(2)) which have antioxidant properties, may even be used as a means of treating cataract directly. Prior to use in treatments, nanoparticle genotoxicity must be tested to assess the extent of any DNA or chromosomal damage. Sister chromatid exchanges were measured and DNA damage investigated using the alkaline COMET assay on cultured human lens epithelial cells, exposed to 5 and 10 microg ml(-1) of CeO(2) nanoparticles (nanoceria). Nanoceria at these dosages did not cause any DNA damage or significant increases in the number of sister chromatid exchanges. The absence of genotoxic effects on lens cells suggests that nanoceria, in the doses and exposures tested in this study, are not deleterious to the eye lens and have the potential for use in studying structural alterations, in developing non-surgical cataract treatments and in investigating other protein folding diseases.

The effect of high concentration and exposure duration of nanoceria on Human Lens Epithelial Cells

Nanotechnology has the potential for treating diseases and conditions of ageing. The eye is particularly vulnerable, because chronic pathologies can lead to sight loss. Human lens epithelial cells were exposed to 10, 20, and 100 μg/mL of negatively charged nanoceria for 48 and 72 hours; DNA damage and cell growth were assessed. Concentrations up to 100 μg/mL for 48 hours did not cause measurable genotoxic effects. For exposures of 72 hours, concentrations above 10 μg/mL showed small but statistically significant differences in DNA damage from negative controls. All treated samples were less damaged than positive controls. Cell growth, monitored for up to 7 days, did not show deviations in cell morphology or growth between treated and untreated samples. Whereas time of exposure may have greater effect than dosage, indicating potential for genotoxicity at higher exposures, human lens epithelial cells can sustain normal growth when exposed to concentrations of nanoceria of up to 100 μg/mL. From the Clinical Editor: Human lens epithelial cells were exposed to various concentrations of negatively charged nanoceria for 48 and 72 hours to assess DNA damage and cell growth. The authors demonstrate that epithelial cells can sustain normal growth when exposed to concentrations of up to 100 μg/mL, with time of exposure having a greater effect than dosage, indicating potential genotoxicity at higher exposures.

Synthesis and luminescence of CePO4:Tb/LaPO4 core/sheath nanowires.

CePO(4):Tb/LaPO(4) nanowires with a core/sheath architecture have been successful synthesized by a facile aqueous chemical method mediated by original CePO(4):Tb aggregation seeds. The seed crystals serve as both a luminescence center and a nucleation site for epitaxial growth. The seed nanocrystals have an irregular sphere-like shape with an average size of around 6.8 nm and a narrow size distribution. When the seed crystals are coated with LaPO(4), the resulting core/sheath CePO(4):Tb/LaPO(4) nanowires have mean diameters of about 7.6 nm and lengths up to 331 nm. Both photo- and x-ray luminescence demonstrate that the LaPO(4) coating increases the luminescence efficiency. These core/sheath structured nanowires may find potential applications in solid state lighting, medical imaging and radiation detection.

CeO2 Nanoparticles have No Detrimental Effect on Eye Lens Proteins

The transparency of the eye lens is vital for maintenance of good image quality to the eye. This is lost when the lens develops a cataract which is a manifestation of changes to the structural proteins and their organisation. Understanding the complex arrangements and interactions of proteins in the lens and how these alter with opacification requires a means of probing the intact tissue. Nanoparticles offer such potential but need to be tested on lens cells and proteins to see whether they cause any detrimental changes. Cerium oxide nanoparticles (nanoceria) of around 5-6nm were prepared and characterised. A concentration of 10μg/ml was introduced into cell cultures from porcine eye lens epithelial cells and from a commercially available human cell line. Transmission electron microscopy of treated samples showed nanoparticles within cells. Proteins extracted from the cultured cells were subjected to chromatography and electrophoresis. Chromatographs and electrophoresis gels showed no difference between treated and control samples from human lens cell cultures. Some slight differences, between treated and control samples, were noted in porcine samples. The results suggest that introduction of nanoceria into cultured cells from the eye lens do not manifest any significant effects on chromatographic or electrophoretic profiles of eye lens proteins.

Fluorescence and drug loading properties of ZnSe:Mn/ZnS-Paclitaxel/SiO2 nanocapsules templated by F127 micelles.

Hydrophobic ZnSe:Mn/ZnS core-shell fluorescence quantum dots (QDs) and anticancer drug paclitaxel (PTX) have been co-loaded into folate conjugated hybrid silica nanocapsules via F127 micelles based soft-template method in a mild aqueous environment at room temperature. The encapsulation of QDs shows a F127: QDs mass ratio dependent behavior, which impact much on the morphology and optical properties of composite nanocapsules. These as prepared composite nanocapsules also exhibit good photoluminescence stability under the temperature ranges from 19°C to 49°C. In addition, the aqueous solubility of PTX (0.1μg/mL) can be efficiently enhanced about 630 times to 62.99μg/mL, and the loaded PTX could be released during 12h sustainably. These tunable fluorescence, enhanced drug loading efficiency and sustained release behavior manifest that the hybrid nanocapsule is a promising theranostic nanoplatform for future combined fluorescence imaging and chemotherapy.

Luminescence of Lanthanide-Dimethyl Sulfoxide Compound Solutions

Dimethyl sulfoxide (DMSO) has the ability to penetrate living tissues without causing significant damage. Of foremost importance to our understanding of the possible functions of DMSO in biological systems is its ability to replace some of the water molecules associated with the cellular constituents or to affect the structure of the omnipresent water. Luminescence probes have been widely used for biological studies such as labeling, imaging, and detection. Luminescence probes formed in DMSO may find new applications. Here luminescence compounds formed by refluxing lanthanide nitrates of Ce, La, Tb, Yb, Nd, Gd, and Eu in DMSO are reported and their luminescence properties investigated. On the basis of their luminescence spectral properties, the compounds can be classified into four classes. For compounds I with Yb, Ce, and La, the excitation and emission spectra are very broad and their excitation or emission peaks are shifted to longer wavelengths when the monitored emission or excitation wavelength is longer. For compounds II with Gd and Nd, both the excitation and emission spectra are very broad but their emission wavelengths change little at different excitation wavelengths. For Tb-DMSO as compound III, both the typical emissions from the f-f transitions of Tb(3+) and a broad emission at 445 nm are observed. At low reaction temperatures, the f-f emissions are dominant, while at high reaction temperatures such as 180 °C, the broad emission at 445 nm is dominant. For compound IV, Eu-DMSO, the dominant emissions are from the f-f transitions of Eu(3+) and only a weak broad emission is observed, which is likely from the d-f transition of Eu(2+) rather than from metal-to-ligand charge transfer states.

Plasmonic CuS nanodisk assembly based composite nanocapsules for NIR-laser-driven synergistic chemo-photothermal cancer therapy

Hydrophobic CuS nanodisk assemblies and the anticancer drug paclitaxel (PTX) have been co-encapsulated into hybrid silica nanocapsules using a triblock copolymer®F127 (PEO106PPO70PEO106) micelle based soft-template method under mild conditions. The as-prepared CuS-PTX/SiO2 composite nanocapsules have excellent biocompatibility, solubility and high colloidal stability in physiological environments and also exhibit an enhanced photothermal conversion efficiency (PCE) of up to 31.2% as a result of the localized surface plasmon resonance (LSPR) effects. Owing to the hydrophobic-hydrophobic interaction and the silica shell protection, the PTX encapsulation ratio could reach 41.25% and the loaded PTX can undergo sustained release and controlled by near infrared (NIR) laser irradiation. In addition, in vitro and in vivo studies demonstrated the remarkable antitumor effects of the CuS-PTX/SiO2 nanocapsules under NIR laser irradiation (980 nm, 1 W cm-2) for 5 minutes. Hence, the designed novel CuS nanodisk assembly based CuS-PTX/SiO2 nanoplatform shows great potential for synergetic chemo-photothermal cancer therapy.

In situ synthesis of MoS2/graphene nanosheets as free-standing and flexible electrode paper for high-efficiency hydrogen evolution reaction

In this article, an exquisite flexible hybrid MoS2/graphene free-standing electrocatalyst paper was fabricated by a one-step in situ solvothermal process. The assembled MoS2/graphene catalysts exhibit significantly enhanced electrocatalytic activity and cycling stability towards the splitting of water in acidic solution. Furthermore, a strategic balance of abundant active sites at the edge of the S–Mo–S layers with efficient electron transfer in the MoS2/graphene hybrid catalyst plays a key role in controlling the electrochemical performance of the MoS2 nanosheets. Most importantly, the hybrid MoS2/graphene nanosheet paper shows excellent flexibility and high electrocatalytic performance under the various bending states. This work demonstrates an opportunity for the development of flexible electrocatalysts, which have potential applications in renewable energy conversion and energy storage systems.