Meng-Yue Gao,Qiao Chen,Wei Li,Ai-Guo Shen,Ji-Ming Hu
High-throughput optical labeling technologies have become increasingly important with the growing demands for molecular detection, disease diagnosis, and drug discovery. In this thought, a series of CN-bridged coordination polymer encapsulated gold nanoparticles have been developed as a universal and interference-free optical label through a facile and auxiliary agent-free self-assembly route. Moreover, surface-enhanced Raman scattering (SERS) emissions of CN-bridge can be tuned flexibly by simple replacement of Fe2+/Fe3+ with other metal ions relying on the synthesis of three Prussian blue analogues encapsulated gold nanoparticles (Au@PBA NPs). Thus, three distinct Raman frequencies have been acquired, which merely replaced the metal irons. On the basis of the potential supermultiplex optical label, space-confined surface-enhanced Raman scattering (SERS) emissions have been realized. Relying on “Abbe theorem”, the focused laser allows the pure and single triple bond-coded SERS emissions to be combined into a unique and independent output, so-called “combined SERS emission” (c-SERS), if the Au@PBA NPs were confined into one micrometer-scale object. This study demonstrated c-SERS may simultaneously provide 2n – 1 optical labels only using n single emissions in the Raman-silent region for micrometer-size objects.
Liang Huang,Jiening Jin,Jing Wang,Chenxing Jiang,Meng Xu,Huimin Wen,Tao Liao,Jun Hu
Controllable integration of gold building blocks into mesoscopic architecture produces improved optical signals with preferable stability for biological sensing. Here, we developed novel optical labels with homogeneous and high-density implanted hydrophobic gold nanoparticles (AuNPs) throughout three-dimensional silica scaffolds. The dendritic silica supports with an extra-large pore size and highly accessible central-radial channels were employed as metal-affinity templates, for anchoring with AuNPs directly from the organic phase. The nano-assemblies exhibited a high unit loading capacity while maintaining the intrinsic optical characteristics of AuNPs. After phase transfer by the alkylsilane intermediate layer and exterior silica shell encapsulation, the nanocomposites revealed an amplified plasmonic absorption signal, excellent colloidal/optical stability and convenient surface functionalization. By integrating the silica labels into the lateral flow immunoassay strip for signal enhancement, the sensitive point-of-care detection of methamphetamine in urine was established. The limit of detection achieved 0.026 ng mL−1, with a detection range from 0.023 to 375 ng mL−1 in a 10 min assay, allows both visual and on-site quantitative analysis. Encouragingly, the potential interfering drugs in the sample matrix showed a negligible influence on the results, validating the superior specificity of the current immunoassay. The newly developed gold-implanted optical labels show prospects for point-of-care testing in a complex biological matrix with the desirable stability and signal amplification.
Dan Zhang,Hongzhi Zheng,Xiaoting Ma,Lina Su,Xiaoqing Gao,Zhiyong Tang,Yan Xu
Circularly polarized room-temperature phosphorescence (CPRTP) is of paramount importance for applications in information encoding, bioimaging, and optoelectronic devices, however, it remains challenging to organize highly efficient CPRTP materials with controlled handedness and long afterglow. Herein, as an outstanding novel finding, it is diclosed that ultralong CPRTP with on-demand chiroptical properties is simple to realize using the earth-abundant cellulose and silica. It is shown that left-handed chiral nematic nanoporous silica films featuring defect photoluminescence enable ultralong CPRTP with an unprecedented control of the handedness. This work presents that the chiral nematic nanoporous silica films display right-handed CPRTP and left-handed CPRTP with the phosphorescence dissymmetry factors up to −0.130 and 0.093 as well as the afterglow lifetimes of 1.094 and 0.949 s, respectively. The potential of the transparent chiral nematic nanoporous silica films, capable of ultralong CPRTP and selective reflection of left-handed circularly polarized light, for the development of anticounterfeiting optical labels is showcased. This work presents a versatile strategy and a step toward the development of ultralong CPRTP materials with on-demand chiroptical properties from readily available defect phosphors for photonic applications.
危险品化学品经营许可证（带存储）