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Propeller-like nanoscale assemblies with exceptionally intense chiroptical activity and strong luminescence are prepared using gold nanorods and upconversion nanoparticles. The circular dichroism intensity of the tetramer reached 80.9 mdeg, with g-factor value of 2.1 × 10(-2) . The enhancement factor of upconversion luminescence is as high as 21.3 in aqueous phase. Attomolar bioanalysis of a cancer biomarker with two model is also achieved, showing potential for early disease diagnosis and environmental monitoring.

In this study, a Cux OS@ZIF-8 nanostructure is fabricated to quantify the levels of hydrogen sulfide (H2 S) in living cells and in vivo. Zeolitic lmidazolate framework-8 (ZIF-8) is chosen as an encapsulation shell to improve the selectivity of this probe. Using this unique nanostructure, ultrasensitive quantification and bioimaging of H2 S in living cells are successfully achieved. The lower limit of detection is 0.8 and 5.3 nmol per 106 cells for circular dichroism and fluorescence modes, respectively. It is found that the chiral Cux OS NPs transformed into achiral Cux S NPs contribute to the ultrasensitive detection. Notably, this probe can also be carried out to detect and track H2 S levels in tumor-bearing animals. The discoveries put forward for the creation of a detection platform for quantitative tracking and analysis in clinic.

Three disease biomarkers can simultaneously be detected at the attomolar level because of a novel surface-enhanced Raman scattering (SERS) encoded silver pyramid sensing system. This newly designed pyramidal sensor with well-controlled geometry exhibits highly sensitive, selective, and reproducible SERS signals, and holds promising potential for biodetection applications.

Chiral inorganic nanomaterials have recently attracted significant attention because of their many important applications, such as in asymmetric catalysis and chiral sensing. Here, chiral iron disulfide quantum dots (FeS2 QDs) are synthesized via chirality transfer using l/d-cysteine (Cys) as chiral ligands. The chiral FeS2 QDs are coassembled with two gelators to produce a cogel (l- or d-[Gel+FeS2 ]) with a g-factor value of ±0.06. Interestingly, the cogels display intense circularly polarized luminescence. More significantly, the degree of twisting (twist pitch) and the diameter of the cogels can be markedly regulated by illumination with circularly polarized light (CPL) in the ranges of 120-213 and 37-65 nm, respectively, which is caused by the CPL-induced electron transfer. This research opens the way for the design of chiroptical devices with a wide range of functions and applications.

Photodynamic therapy (PDT) agent, which generates singlet oxygen (1 O2 ) under light, has attracted significant attention for its broad biological and medical applications. Here, DNA-driven shell-satellite (SS) gold assemblies as chiral photosensitizers are first fabricated. The chiral plasmonic nanostructure, coupling with cysteine enantiomers on its surface, exhibits intense chiroplasmonic activities (-40.2 ± 2.6 mdeg) in the visible region. These chiral SS nanoassemblies have high reactive oxygen species generating efficiency under circular polarized light illumination, resulting in a 1 O2 quantum yield of 1.09. Meanwhile, it is found that SS could be utilized as PDT agent with remarkable efficiency under right circular polarized light irradiation in vitro and in vivo, allowing X-ray computed tomography (CT) and photoacoustics (PA) imaging for tumors simultaneously. The achievements reveal that the enantiomer-dependent and structure-induced nanoassemblies play an important role in PDT effects. The present researches open up a new avenue for cancer diagnose and therapy using chiral nanostructures as multifunctional platform.

This study strategically fabricates multifunctional nanopyramids to allow the ultrasensitive quantification of dual microRNAs (miR-203b and miR-21) in living cells and their responsive bioimaging in vivo. The nanopyramids, composed of Au-Cu9 S5 nanoparticles (NPs), upconversion NPs (UCNPs), and Ag2 S NPs, emit two luminescent signals simultaneously with excitation at 808 nm, arising from the UCNPs at 541 nm in the visible region and from the Ag2 S NPs at 1227 nm in the second window of near-infrared (NIR-II) region. The upconversion luminescence has a linear relationship with miR-203b from 0.13 to 54.54 fmol per 10 µgRNA and a limit of detection (LOD) of 0.09 fmol per 10 µgRNA , whereas the Ag2 S NP luminescence has a linear relationship with miR-21 from 0.37 to 43.56 fmol per 10 µgRNA , with a LOD of 0.23 fmol per 10 µgRNA . Significantly, this study demonstrates that the nanopyramids can be successfully used for miRs-responsive bioimaging in a tumor-bearing animal model. Furthermore, taking advantage of the photothermal capabilities of pyramids, the tumors can also be eliminated completely. These nanopyramids not only overcome the obstacles in the simultaneous detection of multiple miRs at the cellular level but also provide a cancer theranostic platform in vivo.