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Sensitive, selective, especially label-free detection of disease relevant protein biomarkers is highly valuable for clinical diagnosis and disease process monitoring but remains a challenge. Herein, with prostate specific antigen (PSA) as a model target, we have designed a label-free ratiometric fluorescent immunosensor based on three-dimensional (3D) DNA walker and the powerful clustered regularly interspaced short palindromic repeat (CRISPR)/Cas system, with poly(thymine) templated Cu nanoclusters and DAPI as signals. The aptamer-linked activator DNA was designed to convert target recognition event into activate deoxyribonuclease activity of CRISPR/Cas12a system and further cleave oligonucleotides. The cleavage behavior leads to the quenching of copper nanoclusters and stagnation of the cascade amplification progress of 3D DNA nanomachine. The DNA machine is constructed from primer DNA and silica nanospheres loaded by double-stranded DNA (dsDNA) with prominent 3′ end, and movement of the primer DNA is powered by exonuclease (Exo) III via a burnt-bridge mechanism. Without primer DNA, the dyes (DAPI) were embedded in the complementary DNA and emit strong fluorescence. The practical applicability of the biosensor was demonstrated by assay of PSA in human serum with satisfactory result. In addition, this completely label-free method, reduced consumption of antibody, greatly simplify the procedures and saving cost.

Herein, four new cuprous iodide hybrid materials 1–4 were synthesized at room temperature using two types of ligands: imidazoles and triphenylphosphine. Photoluminescence results showed that all the materials exhibited blue emissions with high internal quantum yields (IQYs) ranging from 51% to 64%. Surprisingly, the introduction of triphenylphosphine induced strong aggregation-induced emission (AIE). Additionally, the luminescence lifetimes of these materials were significantly longer, ranging from 11.53 μs to 24.33 μs, which is much longer than those of previous materials. These findings suggest that these materials could be potential candidates for non-rare earth element (REE) lighting phosphors. [ABSTRACT FROM AUTHOR]

Copper iodide organic‐inorganic hybrid materials have been favored by many researchers in the field of solid‐state lighting (SSL) due to their structural diversity and optical adjustability. In this paper, three isomeric copper iodide cluster hybrid materials, Cu4I6(L)2(1), Cu5I4.5Cl2.5(L)2(2) and Cu5I7(L)2) (3) (L=1‐(4‐methylpyrimidin‐2‐yl)‐1,4‐diazabicyclo[2.2.2]octan‐1‐ium), were achieved by adjusting the reaction conditions. The crystal color transit from green, yellow to orange and the internal quantum yield (IQY) increase from 57 %–88 %. All three complexes have good thermal stability, good solution processability, and high quantum yield. And origin and mechanism of luminescence of complexes were further studied. This study can provide ideas and theoretical basis for the regulation of cuprous iodide cluster luminescent materials. [ABSTRACT FROM AUTHOR]

A new luminescent Zn-MOF is synthesized based on a TPE-core ligand TPPE, [Zn(TPPE)2(sdc)2]n (LMOF-1, TPPE = 1,1,2,2-tetrakis(4-(pyridin-4-yl)phenyl)ethene, sdc = 4,4'-(ethene-1,2-diyl)dibenzoic acid). Fluorescence analysis of LMOF-1 shows blue light which can be attributed to the role of ligand-to-metal charge transition (LMCT), indicating that it can be used as a potential LED phosphor. As a luminescent sensor, LMOF-1 has excellent performance in detecting Fe3+, CrO42− and Cr2O72− in water. Significantly, the quenching coefficients (KSV) of Fe3+, CrO42− and Cr2O72− are 6.0 × 103 M−1, 1.58 × 103 M−1 and 2.44 × 103 M−1, respectively. Therefore, LMOF-1 may be an outstanding multi − functional response and recyclable luminescent sensor. [ABSTRACT FROM AUTHOR]

Herein, we synthesized three new LMOFs, [Cd(TPPE)0.5(oba)(H2O)]n (LMOF-1), [Cd2(TPPE)(bpdc)2]n (LMOF-2), and [Cd2(TPPE)(sdc)2]n (LMOF-3) (TPPE = 1,1,2,2-tetra[4-(pyridin-4-yl)phenyl]ethylene, oba = 4,4′-diphenyl ether dicarboxylic acid, bpdc = 4,4′-biphenyl dicarboxylic acid, sdc = 4,4′-styrene dicarboxylic acid), with high quantum yields of 43.74%, 36.68% and 45.89%, respectively, exceeding those reported for most Cd-based LMOFs. All three LMOFs have good detection sensitivity for Fe3+, CrO42− and Cr2O72−. Surprisingly, Na+ can rarely but significantly enhance the fluorescence intensity of LMOF-3, and the detection limit is 1.90 × 10−5 M. This is the first reported LMOF material that can quantitatively analyze Na+ among references. All results indicate that the three MOFs can be developed into phosphor materials and fluorescent chemical sensors for detecting ions in water. [ABSTRACT FROM AUTHOR]