Two crosslinkable poly(p-phenyleneethynylene)s(PPEs): poly[2,5-di(2'-ethyl-hexyloxy)-1,4-phenylenecthynylene] with end-capped vinyl(PPE1) and poly[2,5-di(allyloxy)-1,4-phenyleneethynylene-2,5-di(2'-ethyl...Two crosslinkable poly(p-phenyleneethynylene)s(PPEs): poly[2,5-di(2'-ethyl-hexyloxy)-1,4-phenylenecthynylene] with end-capped vinyl(PPE1) and poly[2,5-di(allyloxy)-1,4-phenyleneethynylene-2,5-di(2'-ethyl-hexyloxy)-1,4-phenyleneethynylene](PPE2) were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction(WXRD), ultraviolet-visible(UV-Vis) absorption, and photoluminescence(PL). The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered(2'-ethyl-hexyl)oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.展开更多
Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their st...Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their structure and optoelectronic properties were investigated through dynamic light scattering(DLS) ,UV and PL spectroscopy.The optical properties of OHOPEL-based water-soluble nanoparticles exhibited the same properties as that found in OHOPEL films,indicating the existence of interchain-aggregation of OHOPELs in the nanoparticles.OHOPEL-based nanoparticles prepared from conjugated oligomers show smaller size and lower dispersity than nanoparticles from conjugated polymers,which means that the structures of water-soluble nanoparticles are linked to the conjugated length.Furthermore,the OHOPEL/PG and OHOPEL/PAA systems produced smaller particles and lower polydispersity than the OHOPEL/PEG system,indicating that there may exist influence of the strength of non-covalent bonds on the size and degree of dispersity of the nanoparticles.展开更多
A novel water-soluble fluorescent amphiphile based on amino polyethylene glycol (PEG-NH2) substituted oligo- (p-phenyleneethynylene) (OPE) was designed and synthesized successfully. Taking anion OPE amphiphile a...A novel water-soluble fluorescent amphiphile based on amino polyethylene glycol (PEG-NH2) substituted oligo- (p-phenyleneethynylene) (OPE) was designed and synthesized successfully. Taking anion OPE amphiphile as a comparison, the photophysical features were investigated through ultraviolet absorption (UV) and photolumines- cence (PL) analyses. Due to the hydrophobic-hydrophilic property of the OPE conjugated molecule, self-assembled nanoparticles with the size ranging from 19.6 to 93.5 nm along with the change of morphology from "grain" to "strawberry" were conveniently prepared via adjusting concentrations of OPE aqueous solution. Interestingly, after aging for a period of time, homogeneous hollow nanospheres were spontaneously constructed with a diameter of about 200 rim. Cytotoxieity test and cellular uptake behavior of the nanoparticles were further investigated to evalu- ate their potential biomedical applications. Subsequently, the promising applications of two-photon cell imaging were explored using human pancreatic cancer cells (PANC-I cells), which indicated that the nanoparticles were mainly located within the cell cytoplasm.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.20771030 and 20671025)
文摘Two crosslinkable poly(p-phenyleneethynylene)s(PPEs): poly[2,5-di(2'-ethyl-hexyloxy)-1,4-phenylenecthynylene] with end-capped vinyl(PPE1) and poly[2,5-di(allyloxy)-1,4-phenyleneethynylene-2,5-di(2'-ethyl-hexyloxy)-1,4-phenyleneethynylene](PPE2) were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction(WXRD), ultraviolet-visible(UV-Vis) absorption, and photoluminescence(PL). The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered(2'-ethyl-hexyl)oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.
基金supported by the National Natural Science Foundation of China(20774043 & 20874048)Key Projcet of the Ministry of Education(104246)+2 种基金State Basic Research Development Program of China(973 Program)(2009CB930600)the Fok Ying-Tong Education Foundation(111051)the Natural Science Foundation of Jiangsu Province(BK2008453)
文摘Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their structure and optoelectronic properties were investigated through dynamic light scattering(DLS) ,UV and PL spectroscopy.The optical properties of OHOPEL-based water-soluble nanoparticles exhibited the same properties as that found in OHOPEL films,indicating the existence of interchain-aggregation of OHOPELs in the nanoparticles.OHOPEL-based nanoparticles prepared from conjugated oligomers show smaller size and lower dispersity than nanoparticles from conjugated polymers,which means that the structures of water-soluble nanoparticles are linked to the conjugated length.Furthermore,the OHOPEL/PG and OHOPEL/PAA systems produced smaller particles and lower polydispersity than the OHOPEL/PEG system,indicating that there may exist influence of the strength of non-covalent bonds on the size and degree of dispersity of the nanoparticles.
文摘A novel water-soluble fluorescent amphiphile based on amino polyethylene glycol (PEG-NH2) substituted oligo- (p-phenyleneethynylene) (OPE) was designed and synthesized successfully. Taking anion OPE amphiphile as a comparison, the photophysical features were investigated through ultraviolet absorption (UV) and photolumines- cence (PL) analyses. Due to the hydrophobic-hydrophilic property of the OPE conjugated molecule, self-assembled nanoparticles with the size ranging from 19.6 to 93.5 nm along with the change of morphology from "grain" to "strawberry" were conveniently prepared via adjusting concentrations of OPE aqueous solution. Interestingly, after aging for a period of time, homogeneous hollow nanospheres were spontaneously constructed with a diameter of about 200 rim. Cytotoxieity test and cellular uptake behavior of the nanoparticles were further investigated to evalu- ate their potential biomedical applications. Subsequently, the promising applications of two-photon cell imaging were explored using human pancreatic cancer cells (PANC-I cells), which indicated that the nanoparticles were mainly located within the cell cytoplasm.