Pu Zhang

AuPd heterostructured nanoplates exhibit high photothermal conversion efficiency (up to 64.7%) for combating drug-resistant bacteria in vitro , a result of optimized electronic synergy and strain at the Au/Pd interface.

Hybrid nanostructures incorporating anisotropic structural components present promising opportunities for developing advanced photothermal agents. Here, we report the controlled synthesis of solid–hollow hybrid nanostructures based on gold–copper (Au–Cu) and demonstrate their photothermal antibacterial properties. Starting from Au nanoplate seeds, we achieve anisotropic deposition to synthesize AuCu and AuAgCu Janus nanostructures. The newly-deposited regions are subsequently transformed into porous architectures via a galvanic replacement reaction mediated by KCl and acetic acid. The introduced nanopores enhance near-infrared (NIR) absorption, thereby improving photothermal conversion efficiency under both 808 nm and 1064 nm laser irradiation and enabling the efficient eradication of multidrug-resistant bacteria. Finite-difference time-domain (FDTD) simulations confirm their optimized plasmonic properties. The current study underscores the potential of morphologically complex hybrid nanostructures for advanced photothermal applications.

In-plane interface engineering of two-dimensional ultrathin CuS–Au and CuS@Au nanohybrids is realized, showcasing the potential in near-infrared photothermal conversion. The synthesis involves creating high-purity ultrathin CuS nanoplates, followed by controlled Au deposition on their edges in two patterns: a layer-by-layer approach for a seamless shell and an island-growth method for isolated nano-islands. This technique precisely manipulates the CuS–Au interface, enhancing their interaction and electronic structure. When irradiated with 808 nm and 1064 nm lasers at 0.4 W m⁻², the optimized CuS–Au hybrids achieve photothermal conversion efficiencies of 67.31% and 32.02%, respectively, along with outstanding photothermal stability. Finite difference time domain (FDTD) simulations suggest that attaching spherical particles to the plate edges significantly boosts electric field strength and temperature distribution under NIR light. Additionally, CuS–Au HNPs-I demonstrated remarkable efficacy in killing prevalent clinical pathogens with 10-minute exposure to near-infrared light, achieving an impressive antibacterial efficiency of over 99.9%. This study provides a versatile strategy for the in-plane interface engineering of two-dimensional hybrid nanostructures, paving the way for efficient photothermal materials.

The effectiveness of photodynamic therapy (PDT) has been greatly restricted by the hypoxic tumor microenvironment and the susceptible resistance of monotherapy. Although nanodrugs based on transition metal complexes capable of integrating PDT with photoactivated chemotherapy (PACT) have garnered tremendous attention as promising candidates for overcoming the above limitations, the therapeutic efficacy of these nanodrugs is still hampered by inadequate loading of active pharmaceutical ingredients (APIs) and the inherent ability of cancer cells to repair damaged DNA. Herein, we developed a photoactivated full-API nanodrug, Ru–T FAND, by one-step self-assembly of RuDPB and TH287. By virtue of its 100 wt% API content and favorable stability in water, the Ru–T FAND exhibited improved cellular uptake behavior and intracellular ¹O₂ generation. Attractively, the Ru–T FAND with triple anti-cancer modalities can photogenerate ¹O₂, photo-release DPB ligand and inhibit the repair of DNA damage, ultimately enhancing its phototherapeutic effect on cancer cells. Importantly, the uncaged DPB ligand from RuDPB emits red fluorescence, enabling real-time monitoring of the drug's absorption, distribution and efficacy. Collectively, the presented photoactivated Ru–T FANDs with multiple anti-cancer mechanisms will expand new horizons for the development of safe, efficient and synergistic tumor phototherapy strategies.

Inorganic pyrophosphate anions (PPi) play a key role in various biological processes and act as an essential indicator for physiological function evaluation and disease diagnosis. However, there is still a lack of available approaches for straightforward, robust, and convenient PPi detection. Herein, we design an on-off-on fluorescent switching nanoprobe employing Fe³⁺-mediated fluorescent sulfur quantum dots (SQDs) for highly robust detection of PPi. The bovine serum protein (BSA)-capped SQDs with fine water dispersibility and good optical stability are synthesized by an H₂O₂-assisted chemical etching reaction. Specifically, Fe³⁺ can strongly induce the aggregation of the SQDs into relatively larger sizes, resulting in aggregation-induced fluorescence quenching behavior. PPi can selectively bind with Fe³⁺ via emulative coordination and in preventing the aggregation of SQDs this is accompanied by recovery of fluorescence. The physicochemical properties of aggregated and disaggregated SQDs have been systematically investigated. Aggregation and disaggregation of the SQDs and the corresponding quenching and recovery of fluorescence occurs and guarantees the high-contrast sensing performance of the SQD system in complex and challenging aquatic environments. Our designed on-off-on nanoswitch holds great potential for the design of elemental quantum dot-based biosensors for the highly robust detection of analytes in the near future.

Aptamer-functionalized Ce⁴⁺-ion-modified C-dots act as catalytic hybrid systems, aptananozymes, catalyzing the H₂O₂ oxidation of dopamine. A series of aptananozymes functionalized with different configurations of the dopamine binding aptamer, DBA, are introduced. All aptananozymes reveal substantially enhanced catalytic activities as compared to the separated Ce⁴⁺-ion-modified C-dots and aptamer constituents, and structure-catalytic functions between the structure and binding modes of the aptamers linked to the C-dots are demonstrated. The enhanced catalytic functions of the aptananozymes are attributed to the aptamer-induced concentration of the reaction substrates in spatial proximity to the Ce⁴⁺-ion-modified C-dots catalytic sites. The oxidation processes driven by the Ce⁴⁺-ion-modified C-dots involve the formation of reactive oxygen species (^•OH radicals). Accordingly, Ce⁴⁺-ion-modified C-dots with the AS1411 aptamer or MUC1 aptamer, recognizing specific biomarkers associated with cancer cells, are employed as targeted catalytic agents for chemodynamic treatment of cancer cells. Treatment of MDA-MB-231 breast cancer cells and MCF-10A epithelial breast cells, as control, with the AS1411 aptamer- or MUC1 aptamer-modified Ce⁴⁺-ion-modified C-dots reveals selective cytotoxicity toward the cancer cells. In vivo experiments reveal that the aptamer-functionalized nanoparticles inhibit MDA-MB-231 tumor growth.