An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunab...An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunable particles in DMF/water mixtures. The polymer nanoparticles can be used for cell imaging, which provides a potential stable fluorescent tool to monitor the distribution of drugs and bioconjugates in living cells.展开更多
A selective DNA sensing with zeptomole detection level is developed based on coulometric measurement of gold nanoparticle （AuNPs）-mediated electron transfer （ET） across a self-assembled monolayer on the gold elect...A selective DNA sensing with zeptomole detection level is developed based on coulometric measurement of gold nanoparticle （AuNPs）-mediated electron transfer （ET） across a self-assembled monolayer on the gold electrode. After immobilization of a thiolated hairpin-structured DNA probe, an alkanethiol monolayer was self-assembled on the resultant electrode to block [Fe（CN）6]3-/4 in a solution from accessing the electrode. In the presence of DNA target, hybridization between the DNA probe and the DNA target breaks the stem duplex of DNA probe. Consequently, stem moiety at the 3＇-end of the DNA probes was removed from the electrode surface and made available for hybridization with the reporter DNA-AuNPs conjugates （reporter DNA-AuNPs）. The thiolated reporter DNA matches the stem moiety at the 3＇-end of the DNA probe. AuNPs were then en- larged by immersing the electrode in a growth solution containing HAuCI4 and H202 after the reporter DNA-AuNPs bound onto the electrode surface. The enlarged AuNPs on the electrode restored the ET between the electrode and the [Fe（CN）6]3 -/4-, as a result, amplified signals were achieved for DNA target detection using the coulometric measurement of Fe（CN）63- elec- tro-reduction by prolonging the electrolysis time. The quantities of ET on the DNA sensor increased with the increase in DNA target concentration through a linear range of 3.0 fM to 1.0 pM when electrolysis time was set to 300 s, and the detection limit was 1.0 fM. Correspondingly, thousands of DNA （zeptomole） copies were detected in 10-μL samples. Furthermore, the DNA sensor showed excellent differentiation ability for single-base mismatch.展开更多
Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs...Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs) was demonstrated using rigid bifacial DNA origami as templates. By tuning the sizes and the fixed location of Au NPs on DNA origami, right-handed and left-handed Au NPs nanostructures were respectively constructed. Gel electrophoresis indicated the formation of the DNA origami-Au NPs complex and transmission electron microscopy(TEM) visually displayed the arrangement of Au NPs in these two chiral structures. The spatial configuration and 3D geometry of Au NPs were further illustrated by the stereographic TEM with tilting angles from ?30° to 30°. This strategy provides a universal approach to construct the asymmetrical 3D geometries, which may have potential applications in biomimicking and nanophotonics.展开更多
A facile approach to assembled virus film with tunable structure is presented.Rod-like tobacco mosaic virus (TMV) was selected as the prototype in this study for its anisotropic structural feature.TMV can either "...A facile approach to assembled virus film with tunable structure is presented.Rod-like tobacco mosaic virus (TMV) was selected as the prototype in this study for its anisotropic structural feature.TMV can either "lie down" or "stand up" on gold substrate by tuning the solution pH.A quartz crystal microbalance with dissipation monitoring was used to monitor the pH-dependent self-assembly behavior of TMV nanoparticles,and atomic force microscopy and single molecule force spectroscopy further confirmed the different assembly structures.展开更多
基金supported by the National Natural Science Foundation of China (20974028, 20974098, and 21174120)the National Basic Research Program of China (2009CB623605)+1 种基金the Research Grants Council of Hong Kong (603509, HKUST2/CRF/10, 604711, and N_HKUST620/11)B.Z.T. thanks the support from the Cao Guangbiao Foundation of Zhejiang University
文摘An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunable particles in DMF/water mixtures. The polymer nanoparticles can be used for cell imaging, which provides a potential stable fluorescent tool to monitor the distribution of drugs and bioconjugates in living cells.
基金the financial support from The National Nature Science Foundation of China (21175089 and 20805029)Program for Changjiang Scholars and Innovative Research Team in University (IRT 1070)
文摘A selective DNA sensing with zeptomole detection level is developed based on coulometric measurement of gold nanoparticle （AuNPs）-mediated electron transfer （ET） across a self-assembled monolayer on the gold electrode. After immobilization of a thiolated hairpin-structured DNA probe, an alkanethiol monolayer was self-assembled on the resultant electrode to block [Fe（CN）6]3-/4 in a solution from accessing the electrode. In the presence of DNA target, hybridization between the DNA probe and the DNA target breaks the stem duplex of DNA probe. Consequently, stem moiety at the 3＇-end of the DNA probes was removed from the electrode surface and made available for hybridization with the reporter DNA-AuNPs conjugates （reporter DNA-AuNPs）. The thiolated reporter DNA matches the stem moiety at the 3＇-end of the DNA probe. AuNPs were then en- larged by immersing the electrode in a growth solution containing HAuCI4 and H202 after the reporter DNA-AuNPs bound onto the electrode surface. The enlarged AuNPs on the electrode restored the ET between the electrode and the [Fe（CN）6]3 -/4-, as a result, amplified signals were achieved for DNA target detection using the coulometric measurement of Fe（CN）63- elec- tro-reduction by prolonging the electrolysis time. The quantities of ET on the DNA sensor increased with the increase in DNA target concentration through a linear range of 3.0 fM to 1.0 pM when electrolysis time was set to 300 s, and the detection limit was 1.0 fM. Correspondingly, thousands of DNA （zeptomole） copies were detected in 10-μL samples. Furthermore, the DNA sensor showed excellent differentiation ability for single-base mismatch.
基金supported by the National Basic Research Program of China (2012CB933301)the National Natural Science Foundation of China (21305070, 21475064)+2 种基金the Natural Science Foundation of Jiangsu Province (BK20130861)the Sci-tech Support Plan of Jiangsu Province (BE2014719)Science Foundation of Nanjing University of Posts and Telecommunications (213005, 214175).
文摘Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs) was demonstrated using rigid bifacial DNA origami as templates. By tuning the sizes and the fixed location of Au NPs on DNA origami, right-handed and left-handed Au NPs nanostructures were respectively constructed. Gel electrophoresis indicated the formation of the DNA origami-Au NPs complex and transmission electron microscopy(TEM) visually displayed the arrangement of Au NPs in these two chiral structures. The spatial configuration and 3D geometry of Au NPs were further illustrated by the stereographic TEM with tilting angles from ?30° to 30°. This strategy provides a universal approach to construct the asymmetrical 3D geometries, which may have potential applications in biomimicking and nanophotonics.
基金supported by the National Natural Science Foundation of China (20423003 & 20774097)Z.S. thanks the NSFC Fund for Creative Research Groups (50921062) for support+1 种基金the financial support from US NSF (DMR-0706431, CHE-0748690)US DoD, US DoE-BES, and the W. M. Keck Foundation
文摘A facile approach to assembled virus film with tunable structure is presented.Rod-like tobacco mosaic virus (TMV) was selected as the prototype in this study for its anisotropic structural feature.TMV can either "lie down" or "stand up" on gold substrate by tuning the solution pH.A quartz crystal microbalance with dissipation monitoring was used to monitor the pH-dependent self-assembly behavior of TMV nanoparticles,and atomic force microscopy and single molecule force spectroscopy further confirmed the different assembly structures.
