Objective: In recent years, semiconducting polymer dots (Pdots)have caught considerable attention for their outstanding optical characteristics in biomedical imaging applications. Not as semiconductor quantum dots, Pdots are composed of nonmetallic material and their biological effects remain unclear. In this work, we investigated the effects of a band new polymer dots on bioactivity of mouse sperm using a computer-aided sperm analysis system(CASA) and an in vitro fertilization (IVF) model. Methods: The semiconducting polymer dots used in this study is CN-PPV Pdots, which emits in the orange wavelength range with high brightness. Epididymal mouse sperm were collected from 7-8weeks old Balb/c mouse. Firstly, CN-PPV Pdots was added into the Human Tubal Fluid (HTF) media at various concentrations (0, 1, 10, 100 nmol/L respectively ), then sperm bioactivity and vitality were evaluated every 10 minutes. Secondly, the treated sperm were co-cultured with matured oocytes in HTF media, fertilization rate and oocytes development were recorded after 24 hours co-incubation. Results: Sperm viability in the control group (0 nmol/L) and experimental group (1, 10,100 nmol/L) were 57.20±4.51%, 58.17±4.81%, 55.50±4.52%, 46.26%±3.83%, respectively. Fertilization rate in different groups showed no obvious differences, control group (0 nmol/L) and experimental group (1, 10, 100 nmol/L) were 38.75±1.71%, 37.01±4.69%, 32.75±1.71%, 35.24±2.37%, respectively. Conclusion: Our data indicated that the CN-PPV Pdots had a very high biocompatibility on sperm in both the activation and the IVF process, even in extreme high Pdots concentration,the sperm bioactivity only got slight restrained. The effect of CN-PPV Pdots seems has no or little toxicity,and the long-term embryonic development has yet to be verified.
Objective: Over the past decade, fluorescent semiconductor nanocrystals, also known as quantum dots (QDs), have been applied in biomedical imaging in vitro and in vivo because of their fascinating optical properties. In this work, we investigated the application of CdTe QDs for tumor fluorescence in vivo imaging. Methods: The transparent dorsal skin fold window chamber (DSFC) was constructed on the 4~6 week-old BALB/c mice. The melanoma cells stably expressing green fluorescent protein ---ZsGreen were transplanted into the chamber and the melanoma DSFC model was established successfully. The water soluble CdTe QDs were synthesized and then administrated in the model through the tail intravenous injection. The fluorescent expression of B16 cells were assayed by fluorescent microscopy, the tumor growth, the blood capillaries distributions and its dynamic changes were observed by stereomicroscopy and laser scanning confocal microscopy. Results: The results demonstrated that the expression efficiency of ZsGreen was 41%, which met the experimental requirement. The tumors was visible inside the chamber after implantation of melanoma cells for 5~6 days, while no obvious changes in mice behaviors were found. After injection of the QDs, CdTe QDs accumulated at the invading edge of a range of solid tumor. We could also observe the tumor cells growth near the blood vessels, the angiogenesis occurred inside the tumor and the local blood capillaries increased. Conclusions: This work provided a new strategy for the tumor in vivo imaging and the development of targeted antineoplastic drugs.
Objective: Nowadays, the nanomaterials have been applied in every aspects of our life, including cosmetics, fresh-keeping, antisepsis and medicines. However, we know little about the toxic effects of nanoparticles towards plants. In this thesis, we synthesized quantum dots (QDs), and then toxicity and invasive effects of QDs for mung beans were investigated. Methods: We synthesised red CdTe QDs in water sphase with L-Cystein stabilizers, then prepared different concentration of QDs solution to cultivate mung bean plant, the radical length of mung beans was measured after four days every day, after 7 days, the distribution of QDs in mung bean plant was recorded under the microscopic. Results: The result showed the QDs inhibited the growth of mung beans, the higher the concentration of QDs was, the greater the inhibition effect was. After 7 days, the radicle average lengths of mung beans in different concentrations of QDs solution（blank 0.1μmol/L 0.2μmol/L 0.5 μmol/L 1 μmol/L）were 19.350± 0.427, 14.050± 0.879, 10.525± 0.554, 7.250± 0.522, 7.650± 0.229. The QDs mostly adhered onto the root surface and hairs. Conclusion: In conclusion, the QDs synthesized with L-cystein have effects on the growth of mung beans. However, it is necessary to do more experiments to confirm the mechanism of the toxicity effect of QDs on plants.