Anisotropic nanopatterns have potentials in constructing novel plasmonic structures which have various applications in such as super-resolution microscopy, medicine, and sensors. However, it remains challenging to build big anisotropic nanopatterns that are suitable for big noble metal nanoparticles. Herein, we report a simple and reliable strategy for constructing DNA origami-based big anisotropic nanopatterns with controlled size and shape, nanoscale resolution, and fully addressability. Two kinds of basic DNA origami nanoblocks-cross-shaped and rectangular DNA origami units were used. We have demonstrated that by encoding nanoblocks' edges, anisotropic higher-order nanopatterns, such as dimer, trimer, tetramer and mini "windmill" like pentamer nanopatterns could be constructed. To show the potential use as template to direct the assembly of anisotropic nanoparticles arrays, a proof of concept work was conducted by anchoring streptavidin nanoparticles on the "windmill" template to form a chiral array. Significantly, these nanopatterns have the sizes of hundreds of nanometers, which are in principle also suitable for big noble metal nanoparticles arrays.
We report a novel nanotechnology-based approach for the highly efficient catalytic oxidation of phenols and their removal from wastewater.We use a nanocomplex made of multi-walled carbon nanotubes(MWNTs)and magnetic nanoparticles(MNPs).This nanocomplex retains the magnetic properties of individual MNPs and can be effectively separated under an external magnetic fi eld.More importantly,the formation of the nanocomplex enhances the intrinsic peroxidase-like activity of the MNPs that can catalyze the reduction of hydrogen peroxide(H2O2).Significantly,in the presence of H2O2,this nanocomplex catalyzes the oxidation of phenols with high effi ciency,generating insoluble polyaromatic products that can be readily separated from water.
Xiaolei ZuoCheng PengQing HuangShiping SongLihua WangDi LiChunhai Fan
Graphene and its derivative,graphene oxide (GO) have been substantively used as the main framework for dispersing or building nanoarchitectures because of their excellent properties in electronics and catalysis.The requirement to obtain superior graphene-metal hybrid nanomaterials has led us to explore a facile way to design 4-aminobenzenethiol/1-hexanethiolate-protected gold nanoparticles (aAuNPs)-functionalized graphene oxide composite (aAuNPs-GO) in solution.We demonstrate that when aAuNPs with amino groups are exposed to GO,well-dispersed coverage of Au nanoparticles are mainly observed on the edge of GO sheet.In contrast,when 1-hexanethiolate-protected gold nanoparticles (hAuNPs) without amino groups are exposed to GO,hAuNPs simply aggregate on the surface of GO.This indicates that amino groups located on the surface of Au nanoparticles are an essential prerequisite for attachment of nearly monodispersed aAuNPs.The strategy described here for the fabrication of aAuNPs-GO provides a straightforward approach to develop graphene-based nanocomposites with undamaged sheets structure and good solubility and also improve the conductivity of GO sheets evidently.
A novel nano-and micro-integrated protein chip(NMIPC)that can detect proteins with ultrahigh sensitivity has been fabricated.A microfl uidic network(μFN)was used to construct the protein chips,which allowed facile patterning of proteins and subsequent biomolecular recognition.Aqueous phase-synthesized,water-soluble fl uorescent CdTe/CdS core-shell quantum dots(aqQDs),having high quantum yield and high photostability,were used as the signaling probe.Importantly,it was found that aqQDs were compatible with microfluidic format assays,which afforded highly sensitive protein chips for cancer biomarker assays.
Juan YanMei HuDi LiYao HeRui ZhaoXingyu JiangShiping SongLianhui WangChunhai Fan
A highly sensitive method for the detection of a breast cancer-associated BRCA-1 gene is reported. The detection is based on a classical sandwich-type assay using horseradish peroxidase (HRP) as a catalytic label and electrodeposited Os2+/3+ conducting polymer (PAA-PVI-Os) as a redox mediator. Target DNA could be detected by the HRP-catalyzed reduction of H2O2, leading to a limit of detection as low as 10 fM.