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Reactive oxygen species (ROS)-mediated mitochondrial dysfunction is one of the major pathological mechanisms of Parkinson's disease. Using inorganic nanomaterials to scavenge ROS has drawn significant interest and can prevent ROSmediated neurological disorders. We prepared uniform Cu x O nanoparticle clusters (NCs) with an average size of 65 ± 7 nm, using phenylalanine (Phe) as the structure-directing agent. These Cu x O NCs functionally mimicked the activities of peroxidase, superoxide dismutase, catalase, and glutathione peroxidase. Because they eliminated ROS, the Cu x O NCs inhibited neurotoxicity in a cellular model of Parkinson's disease and rescued the memory loss of mice with Parkinson's disease. The biocompatibility and multiple enzyme-mimicking activities of Cu x O NCs offer new opportunities for the application of NCs in biomedicine, biosensing, and biocatalysis.

Gene editing is an important genetic engineering technique that enables gene manipulation at the molecular level. It mainly relies on engineered nucleases of biological origin, whose precise functions cannot be replicated in any currently known abiotic artificial material. Here, we show that chiral cysteine-modified CdTe nanoparticles can specifically recognize and, following photonic excitation, cut at the restriction site GAT'ATC (' indicates the cut site) in double-stranded DNA exceeding 90 base pairs, mimicking a restriction endonuclease. Although photoinduced reactive oxygen species are found to be responsible for the cleavage activity, the sequence selectivity arises from the affinity between cysteine and the conformation of the specific DNA sequence, as confirmed by quantum-chemical calculations. In addition, we demonstrate non-enzymatic sequence-specific DNA incision in living cells and in vivo using these CdTe nanoparticles, which may help in the design of abiotic materials for gene editing and other biological applications.

In this study, a hybrid nanoassembly consisting of an upconversion nanoparticle (UCNP) core and a zeolitic imidazolate framework-8 (ZIF) shell encapsulated with chiral NiSx NPs

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Gold‐gap‐silver nanostructures (GGS NSs) with interior nanobridged gaps are enantioselectively fabricated. Guided by l/d‐cysteine, the GGS‐L/D (L/D represents l/d‐cysteine) NSs show reversed plasmon‐induced circular dichroism (CD) signals in the visible region. It is found that the nanogap plays a key role in the plasmonic CD of GGS NSs and the chiroptical response can be tailored by adjusting the amount of cysteine. The anisotropy factor of GGS‐L/D NSs with a 0.5 nm interior gap at 430 nm is as high as ≈0.01. The circularly polarized photocatalytic activity of GGS NSs is examined. It is shown that upon irradiation with left‐circularly polarized light, the catalytic efficiency of GGS‐L NSs is 73‐fold and 17‐fold higher than that of Au nanoparticles (NPs) and Au@Ag core–shell NPs, respectively. Upon irradiation with right‐circularly polarized light, the catalytic activity of GGS‐D NSs is about 71 times and 17 times higher than that of Au NPs and Au@Ag core–shell NPs, respectively. These unique chiral NSs with high plasmonic response can be applied to enantioselective catalysis.

nanostructures, both static and dynamic. [8] According to the material composition and underlying mechanisms of chiral nanostructures, Chen and co-workers summarized their preparation methods and properties. [10] Nam and co-workers summarized the chiral assemblies of plasmonic nanostructures enabled by biomolecules (amino acids, peptides, DNA, etc.). [11] After paying great attention to the preparation, characterization, and optical properties of chiral materials, researchers are now focusing on their potential applications, [12] such as optical devices, [13] chiral catalysis, [14] chiral memory, [15] chiral detection, [16] biolabeling, [17] chiral recognition and separation, [18] and others. [19] This progress report will focus on the bioapplications of chiral materials. Herein, first the general design principles of chirality-based biosensors will be introduced. Subsequently, the focus will shift to chiral sensors based on chiral semiconductor nanoparticles, followed by a description of chiral metal-nanoparticle-based probes in Section 4. Next, a variety of chiral sensors using chiral nanoassemblies will be discussed in Section 5. Sections 6 and 7 will review probes based on chiral meta-materials and metalorganic frameworks (MOFs) respectively. Biosensors based on other chiral materials will also be summarized. Finally, a brief conclusion and a perspective on the future development of chiral-material-based sensors will be provided.

In this study, we have first developed a rapid and sensitive strip immunosensor based on two heterogeneously-sized gold nanoparticles (Au NPs) probes for the detection of trace lead ions in drinking water. The sensitivity was 4-fold higher than that of the conventional LFA under the optimized conditions. The visual limit of detection (LOD) of the amplified method for qualitative detection lead ions was 2 ng/mL and the LOD for semi-quantitative detection could go down to 0.19 ng/mL using a scanning reader. The method suffered from no interference from other metal ions and could be used to detect trace lead ions in drinking water without sample enrichment. The recovery of the test samples ranged from 96% to 103%. As the detection method could be accomplished within 15 min, this method could be used as a potential tool for preliminary monitoring of lead contamination in drinking water.