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ABSTRACT: Engineered nanoparticles (NPs) can produce negative impacts on human health even in low doses. In this study, Gd2O3 nanoparticles were synthesized via the polyol route and coated with silicon to form particles with different sizes. Although all the SiO2/Gd2O3 NPs did not induce obvious cell death at 10 microg/mL on a macrophage-like cell line (RAW 264.7), their DNA damaging effects, which is measured by single cell gel electrophoresis (SCGE), is prominent in cells treated with the sample with an overall size of 120 nm. Besides, the NPs with core size of 20 nm induced greater damaging effect than NPs with similar total size but core size of 50 nm. Further test applying the modified SCGE with endonuclease III indicated that the DNA damaging effect was greatly associated with oxide pyridine after the treatment. Using immunoblotting, we found that p53 protein is activated and accumulated after the damage occurred. These results provide a new insight into the adverse effect of nanoparticles with core-shell structures, that not only the overall size but the core size of the particles determines their effect in cells.
Journal of Nanoscience and Nanotechnology 02/2013; 13(2):1270-3. · 1.56 Impact Factor
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ABSTRACT: Upconverting nanoparticles (UCNPs) have attracted considerable attention as potential photosensitizer carriers for photodynamic therapy (PDT) in deep tissues. In this work, a new and efficient NIR photosensitizing nanoplatform for PDT based on red-emitting UCNPs is designed. The red emission band matches well with the efficient absorption bands of the widely used commercially available photosensitizers (Ps), benefiting the fluorescence resonance energy transfer (FRET) from UCNPs to the attached photosensitizers and thus efficiently activating them to generate cytotoxic singlet oxygen. Three commonly used photosensitizers, including chlorine e6 (Ce6), zinc phthalocyanine (ZnPc) and methylene blue (MB), are loaded onto the alpha-cyclodextrin-modified UCNPs to form Ps@UCNPs complexes that efficiently produce singlet oxygen to kill cancer cells under 980 nm near-infrared excitation. Moreover, two different kinds of drugs are co-loaded onto these nanoparticles: chemotherapy drug doxorubicin and PDT agent Ce6. The combinational therapy based on doxorubicin (DOX)-induced chemotherapy and Ce6-triggered PDT exhibits higher therapeutic efficacy relative to the individual means for cancer therapy in vitro.
Small 12/2012; · 8.35 Impact Factor
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Wenyan Yin,
Lina Zhao,
Liangjun Zhou, Zhanjun Gu,
Xiaoxiao Liu,
Gan Tian,
Shan Jin,
Liang Yan,
Wenlu Ren,
Gengmei Xing,
Yuliang Zhao
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ABSTRACT: Under 980 nm near-infrared (NIR) excitation, upconversion luminescent (UCL) emission of GdF(3):Yb,Er upconversion nanoparticles (UCNPs) synthesized by a simple and green hydrothermal process can be tuned from yellow to red by varying the concentration of dopant Li(+) ions. A possible mechanism for enhanced red upconverted radiation is proposed. A layer of silica was coated onto the surface of GdF(3):Yb,Er,Li UCNPs to improve their biocompatibility. The silica-coated GdF(3):Yb,Er,Li UCNPs show great advantages in cell labeling and in vivo optical imaging. Moreover, GdF(3) UCNPs also exhibited a positive contrast effect in T(1)-weighted magnetic resonance imaging (MRI). These results suggest that the GdF(3) UCNPs could act as dual-modality biolabels for optical imaging and MRI.
Chemistry 06/2012; 18(30):9239-45. · 5.93 Impact Factor
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ABSTRACT: Here, dual-modal bioprobes for combined optical and magnetic resonance (MR) imaging are reported. Gadolinium orthophosphate (GdPO(4)) nanorods co-doped with light-emitting lanthanide ions have been successfully prepared through a hydrothermal method. An efficient downconversion luminescence from Ce/Tb or Eu doped GdPO(4) nanorods and upconversion luminescence from Yb/Er co-doped GdPO(4) nanorods are observed, respectively, which offers the optical modality for the nanoprobes. Notably, we first report the upconversion phenomenon based on the GdPO(4) matrix under 980 nm near infrared irradiation. The possibility of using these nanoprobes with downconversion and upconversion luminescent emissions for optical cell imaging is also demonstrated. Furthermore, these Gd(3+)-containing nanophosphors show good positive signal-enhancement ability when performed under a 4.7 T MR imaging scanner, indicating they have potential as T(1) MR imaging contrast agents. Thus, nanoprobes based on GdPO(4) nanophosphors are shown to provide the dual modality of optical and MR imaging.
Nanoscale 05/2012; 4(12):3754-60. · 5.91 Impact Factor
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Gan Tian, Zhanjun Gu,
Liangjun Zhou,
Wenyan Yin,
Xiaoxiao Liu,
Liang Yan,
Shan Jin,
Wenlu Ren,
Gengmei Xing,
Shoujian Li,
Yuliang Zhao
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ABSTRACT: Pure dark red emission (650-670 nm) of NaYF(4):Yb/Er upconversion nanoparticles (UCNPs) is achieved by manganese ions (Mn(2+)) doping. In addition, the Mn(2+)-doping can also control the crystalline phase and size of the resulting UCNPs simultaneously. Drug delivery studies suggest the promise of these UCNPs as drug carriers for intracellular drug delivery and eventually as a multifunctional nanoplatform for simultaneous diagnosis and therapy.
Advanced Materials 03/2012; 24(9):1226-31. · 13.88 Impact Factor
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Gan Tian, Zhanjun Gu,
Xiaoxiao Liu,
Liangjun Zhou,
Wenyan Yin,
Liang Yan,
Shan Jin,
Wenlu Ren,
Gengmei Xing,
Shoujian Li,
Yuliang Zhao
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ABSTRACT: Rare-earth (RE)-doped gadolinium oxide (Gd2O3) hollow nanospheres have been successfully prepared on a large scale via a template-directed method using hydrothermal carbon spheres as sacrificed templates. Scanning electron microscope and transmission electron microscope images reveal that these hollow-structured nanospheres have the mesoporous shells that are composed of a large amount of uniform nanoparticles. By doping the RE ions (Yb/Er) into the Gd2O3 host matrix, these NPs emitted bright multicolored upconversion emissions that can be fine-tuned from green to red by adjusting the codoped Yb/Er ratio under 980 nm NIR laser excitation. The possibility of using these upconversion nanoparticles for optical imaging in vivo has been demonstrated. It was also shown that these Gd2O3 nanospheres brightened the T1-weighted images and enhanced the r1 relaxivity of water protons, which suggested that they could act as T1 contrast agents for magnetic resonance (MR) imaging. Moreover, these hollow spheres can be used as drug delivery host carriers, and drug storage/release properties were investigated using ibuprofen as the model drug. As a result, the so-prepared nanoscaled Gd2O3 hollow spheres bearing upconversion luminescence, MR imaging, and drug delivery capabilities could be potentially employed for simultaneous MR/fluorescent imaging and therapeutic applications.
11/2011;
