Rapid and sensitive identification of tumor biomarker or cancer cells in their nascent stage based on surface-enhanced Raman scattering (SERS) is still an attractive challenge due to the low molecular affinity for the metal surface, the complexity of the sample, and low-efficiency use of hot spots in one- or two-dimensional geometries. Here, we demonstrated a novel kind of renewable CuFeSe2/Au heterostructured nanospheres that are hierarchically porous for specific and sensitive detection of lung cancer biomarkers of aldehydes and lung cancer cells. The heterostructured nanospheres were constructed by loading an Au shell formed by photoreduction on the CuFeSe2 frameworks. P-aminothiophenol (4-ATP) as a Raman-active probe molecule was first grafted on CuFeSe2/Au nanospheres, and then the gaseous aldehyde molecules were sensitively bonded onto the nanospheres by formation of a CN bond with a detection limit of 1.0 ppb. Moreover, the resulting folic acid (FA)-conjugated nanospheres have a high SERS activity to Rhodamine B isothiocyanate (RBITC), which can be used to specifically recognize and sensitively detect the A549 cells. Our study suggested that the synthesized renewable CuFeSe2/Au heterostructured nanospheres as a multimodal platform could find a wide range of applications in the fields of medicine, biotechnology, and environmental sciences.

IIn vivo synthesis of toxic drugs against tumors based on the specific features of tumor microenvironment is critical to ensuring specific antitumor efficacy. However, how to achieve in situ high-yield...

New strategies for portable detection of highly toxic environmental pollutants are still in urgent need. Here, through Pd 2+ and methylene blue (MB) coordination, photothermal two-dimensional palladium coordination polymers nanosheets (2D PdCPsNSs) have been synthesized for sensitive photothermal detection of H 2 S. The sensing mechanism is based on the decomposing effect of H 2 S to 2D PdCPsNSs, accompanied by the decrease of PdCPsNSs concentration and the increase of MB concentration. Upon H 2 S addition, the heat released from the 2D PdCPsNSs under 808 nm lasers irradiation decreased, and the heat released from the MB increased under 650 nm lasers irradiation, respectively. Such temperature change signals could be easily detected by a portable thermometer. The 2D PdCPsNSs showed highly sensitive ratiometric response to H 2 S with a detection limit of 30 nM. In addition, such probe presents an excellent selective ratiometric response to H 2 S relative to other anionic species and thiols because of the specific interaction between Pd 2+ and H 2 S. Moreover, the probe was suitable for the ratiometric determination of H 2 S in different actual water samples, providing a promising platform for convenient, stable, and universal analysis of H 2 S.

The synergistic nanotheranostics of reactive oxygen species (ROS) augment or phototherapy has been a promising method within synergistic oncotherapy. However, it is still hindered by sophisticated design and fabrication, lack of a multimodal synergistic effect, and hypoxia-associated poor photodynamic therapy (PDT) efficacy. Herein, a kind of porous shuttle-shape platinum (IV) methylene blue (Mb) coordination polymer nanotheranostics-loaded 10-hydroxycamptothecin (CPT) is fabricated to address the abovementioned limitations. Our nanoreactors possess spatiotemporally controlled O2 self-supply, self-sufficient singlet oxygen (1O2), and outstanding photothermal effect. Once they are taken up by tumor cells, nanoreactors as a cascade catalyst can efficiently catalyze degradation of the endogenous hydrogen peroxide (H2O2) into O2 to alleviate tumor hypoxia. The production of O2 can ensure enhanced PDT. Subsequently, under both stimuli of external red light irradiation and internal lysosomal acidity, nanoreactors can achieve the on-demand release of CPT to augment in situ mitochondrial ROS and highly efficient tumor ablation via phototherapy. Moreover, under the guidance of near-infrared (NIR) fluorescent imaging, our nanoreactors exhibit strongly synergistic potency for treatment of hypoxic tumors while reducing damages against normal tissues and organs. Collectively, shuttle-shape platinum-coordinated nanoreactors with augmented ROS capacity and enhanced phototherapy efficiency can be regarded as a novel tumor theranostic agent and further promote the research of synergistic oncotherapy.

Although substantial efforts have been made toward the synthesis of noble metal-semiconductor heteronanostructures, direct in situ synthesis of two-dimensional (2D) core-shell semiconductor@noble metal heterostructured nanosheets remains largely unexplored. Herein, we report the synthesis of a novel 2D core-shell CuFeSe@Au heterostructured nanosheet with an amorphous core and a crystalline shell based on the reversed growth of Au nanosheets on the CuFeSe frameworks under near-infrared (NIR) illumination. The nanosheet exhibits strong absorbance in the NIR region, and the valence band top of CuFeSe@Au nanosheets is higher than the oxidation potential of O/HO. Owing to the unique structural features, the resulting nanosheets show excellent photocatalytic activity and high stability toward water oxidation with an O generation rate up to 3.48 mmol h g compared to those of the constituent materials under NIR light irradiation (λ > 850 nm). This work brings new opportunities to prepare 2D core-shell semiconductor@noble metal heterostructured nanosheets, which can be applied as photocatalysts toward water splitting and solar energy conversion at long wavelengths.

A photochemical strategy using photoinduced methylene blue radicals for the green synthesis of ultrathin Au nanosheets. The resulting Au nanosheets show highly sensitive recognition of cancer cells and efficient activity and selectivity toward the hydrogenation of α,β-unsaturated aldehydes.

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Sub-10 nm monodisperse alkaline-earth sulfide nanodots (ASNDs) with bright near-infrared (NIR)-excitation fluorescence and adjustable emission wavelength were prepared by a thermal decomposition method for the first time. The ASNDs exhibited high NIR-to-vis conversion efficiency and served as multicolor fluorescent labels in the proposed miR-224 assay. Targeted detection of the miR-224 level and single-nucleotide variation in miR-224 was carried out on a smartphone-based platform using a hybridization chain reaction (HCR) amplification strategy. In the presence of miR-224, the ASND-labeled HCR probes self-assembled on the surface of the diagnosis kits, generating strong fluorescent signals linearly proportional to miR-224 contents in the range of 10− 2000 fM. Significantly, mutations in miR-224 led to the variation in the fluorescence intensity ratio in RGB channels. Simultaneously, evident changes of fluorescent brightness and color were easily visualized by the naked eye, which enabled on-site discrimination of miR-224 with different mutant loci. This work provides a novel preparation approach for ultrasmall NIR excitation sulfide nanodots and reveals the potential of the as-synthesized ASNDs in point-of-care (POC) nucleic acid testing. Further, it may provide a handheld platform for miRNA single-nucleotide polymorphism analysis.