β-NaYF4:Yb,Er nanoparticles (NPs) are one of the most efficient upconversion materials, which can convert near-infrared light to higher-energy light through multiple photon absorptions or energy transfer. In addition...β-NaYF4:Yb,Er nanoparticles (NPs) are one of the most efficient upconversion materials, which can convert near-infrared light to higher-energy light through multiple photon absorptions or energy transfer. In addition, they may be attractive alternative donors for luminescence resonance energy transfer (LRET) studies, because of their sharp absorption and emission profiles, high quantum yields, large anti-stokes shifts, long lifetime, low toxicity, and superior photo-stability. In principle, many problems of fluorescence resonance energy transfer (FRET), such as excitation of acceptors, emission overlaps between donors and acceptors, high background noise, potential toxicity, and instability, can be overcome using β-NaYF4:Yb,Er NPs as energy donors. Because the organic coating induced separation can significantly reduce the energy transfer efficiency and aqueous FRET system is difficult to be applied in devices, we demonstrate a novel NP-dye LRET system in solid state. The emission of the β-NaYF4:Yb,Er NPs at 539 nm overlaps with the absorption of the tetrametrylrhodarnine isothiocyante (TRITC), satisfying the requirement of LRET process. Since TRITC molecules are adsorbed on the β-NaYF4:Yb,Er NPs by an electrostatic interaction, the interaction distance is suitable for LRET without any further modulation. The resultant solid LRET system is ready for the further applications for devices.展开更多
In this article, the preparation of core-shell fluorescent dye nanoparticles doped with rhodamine B isothiocyanate by using novel method is reported, which involves synchronous hydrolysis of tetraethoxysilane(TEOS) in...In this article, the preparation of core-shell fluorescent dye nanoparticles doped with rhodamine B isothiocyanate by using novel method is reported, which involves synchronous hydrolysis of tetraethoxysilane(TEOS) in water in oil microemulsion with the combination of N-(β-amimoethyl)-γ-amino propyltriethoxy-silane(AEAPS) and rhodamine B isothiocyanate(TRITC). This method conquers the disadvantages of traditional preparation method about organic dye doped core-shell nanoparticles such as the leakage of fluorescent dyes and the low encapsulation efficiency of fluorescent dyes. The fluorescent nanoparticle prepared by using the novel method have the advantages such as high fluorescence and good fluorescent stability, which are hopeful to be applied in the field of biological labelling.展开更多
By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were...By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were studied with fluorescence probe technique and confocal laser scanning microscopy. There were a lot of actin filaments （AFs） impenetrate the cell wall, but the AFs with red fluorescence were absent when the cells were treated with cytochalasin D before fixation; the same result was obtained when the cells were treated with unlabeled phalloidin. These results indicate the presence of Factin in the intercellular channels and that it is related to the plasmodesmata and intercellular trafficking of macromolecules.展开更多
The interphase nuclei of parenchyma cells and epidermal cells of garlic ( Allium sativum L.) clove were labelled with rabbit anti_actin antibody and FITC_conjugated goat anti_rabbit IgG antibody. The authors observ...The interphase nuclei of parenchyma cells and epidermal cells of garlic ( Allium sativum L.) clove were labelled with rabbit anti_actin antibody and FITC_conjugated goat anti_rabbit IgG antibody. The authors observed results with fluorescence microscopy and confocal laser scanning microscopy. The nuclei showed prominent green_yellow fluorescence, indicating the presence of actin in the nuclei. Fluorescence examination with TRITC_phalloidin showed distinctive red fluorescence in the nuclei, indicating that F_actin is present in the nuclei. Confocal laser scanning microscopy indicated the presence of F_actin containing network structures in the nuclei, but the network structures were absent and the nuclei still showed red fluorescence when the cells were treated with cytochalasin D before fixation; the red fluorescence in the nuclei was hard to be observed when the cells were treated with unlabelled phalloidin before the cells were stained with TRITC_phalloidin. These results indicate that F_actin is in the nuclei and forms network structures in the nuclei of garlic cells.展开更多
Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were d...Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were distributed in the extreme tip as well as pollen tubes in a form of network.Fluorescent granules or circles of various sizes were frequently found that continued with the filamentous structures. In addition, a more brightly stained structure, possibly Mf organizing center, was observed. Treatment of pollen tubes with cytochalasin D(CD)for increasing time intervals (5-40 minutes) caused gradual reduction of strands until flurescent granules filled up the pollen tubes. Mcanwhile, cytoplasmie streaming was inhibited completely. Though closely associated with vegetative nuclei (VN) and generative cells (GC), AFs were not found in the cytoplasm of GC.Mg++concentration greatly affected the isolated Mfs.展开更多
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20821091 and 20671005)the National Natural Science Foundation of China & Research Grants Council (20731160001)the Ministry of Science and Technology of China (Grant No. 2006CB601104)
文摘β-NaYF4:Yb,Er nanoparticles (NPs) are one of the most efficient upconversion materials, which can convert near-infrared light to higher-energy light through multiple photon absorptions or energy transfer. In addition, they may be attractive alternative donors for luminescence resonance energy transfer (LRET) studies, because of their sharp absorption and emission profiles, high quantum yields, large anti-stokes shifts, long lifetime, low toxicity, and superior photo-stability. In principle, many problems of fluorescence resonance energy transfer (FRET), such as excitation of acceptors, emission overlaps between donors and acceptors, high background noise, potential toxicity, and instability, can be overcome using β-NaYF4:Yb,Er NPs as energy donors. Because the organic coating induced separation can significantly reduce the energy transfer efficiency and aqueous FRET system is difficult to be applied in devices, we demonstrate a novel NP-dye LRET system in solid state. The emission of the β-NaYF4:Yb,Er NPs at 539 nm overlaps with the absorption of the tetrametrylrhodarnine isothiocyante (TRITC), satisfying the requirement of LRET process. Since TRITC molecules are adsorbed on the β-NaYF4:Yb,Er NPs by an electrostatic interaction, the interaction distance is suitable for LRET without any further modulation. The resultant solid LRET system is ready for the further applications for devices.
文摘In this article, the preparation of core-shell fluorescent dye nanoparticles doped with rhodamine B isothiocyanate by using novel method is reported, which involves synchronous hydrolysis of tetraethoxysilane(TEOS) in water in oil microemulsion with the combination of N-(β-amimoethyl)-γ-amino propyltriethoxy-silane(AEAPS) and rhodamine B isothiocyanate(TRITC). This method conquers the disadvantages of traditional preparation method about organic dye doped core-shell nanoparticles such as the leakage of fluorescent dyes and the low encapsulation efficiency of fluorescent dyes. The fluorescent nanoparticle prepared by using the novel method have the advantages such as high fluorescence and good fluorescent stability, which are hopeful to be applied in the field of biological labelling.
文摘By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were studied with fluorescence probe technique and confocal laser scanning microscopy. There were a lot of actin filaments （AFs） impenetrate the cell wall, but the AFs with red fluorescence were absent when the cells were treated with cytochalasin D before fixation; the same result was obtained when the cells were treated with unlabeled phalloidin. These results indicate the presence of Factin in the intercellular channels and that it is related to the plasmodesmata and intercellular trafficking of macromolecules.
文摘The interphase nuclei of parenchyma cells and epidermal cells of garlic ( Allium sativum L.) clove were labelled with rabbit anti_actin antibody and FITC_conjugated goat anti_rabbit IgG antibody. The authors observed results with fluorescence microscopy and confocal laser scanning microscopy. The nuclei showed prominent green_yellow fluorescence, indicating the presence of actin in the nuclei. Fluorescence examination with TRITC_phalloidin showed distinctive red fluorescence in the nuclei, indicating that F_actin is present in the nuclei. Confocal laser scanning microscopy indicated the presence of F_actin containing network structures in the nuclei, but the network structures were absent and the nuclei still showed red fluorescence when the cells were treated with cytochalasin D before fixation; the red fluorescence in the nuclei was hard to be observed when the cells were treated with unlabelled phalloidin before the cells were stained with TRITC_phalloidin. These results indicate that F_actin is in the nuclei and forms network structures in the nuclei of garlic cells.
文摘Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were distributed in the extreme tip as well as pollen tubes in a form of network.Fluorescent granules or circles of various sizes were frequently found that continued with the filamentous structures. In addition, a more brightly stained structure, possibly Mf organizing center, was observed. Treatment of pollen tubes with cytochalasin D(CD)for increasing time intervals (5-40 minutes) caused gradual reduction of strands until flurescent granules filled up the pollen tubes. Mcanwhile, cytoplasmie streaming was inhibited completely. Though closely associated with vegetative nuclei (VN) and generative cells (GC), AFs were not found in the cytoplasm of GC.Mg++concentration greatly affected the isolated Mfs.
