ACS Nano最新文献

Exposure to micro- and nanoplastics (MNPs) has been implicated in potential cardiotoxicity. However, in vitro models based on cardiomyocyte cell lines lack crucial cardiac characteristics, while interspecies differences in animal models compromise the reliability of the conclusions. In addition, current research has predominantly focused on single-time point exposures to MNPs, neglecting comparative analyses of cardiac injury across early and late stages. Moreover, there remains a large gap in understanding the susceptibility to MNPs under pathological conditions. To address these limitations, this study integrated cardiac organoids (COs) and organ-on-a-chip (OoC) technology to develop the cardiac organoid-on-a-chip (COoC), which was validated for cardiotoxicity evaluation through multiple dimensions. Based on COoC, we conducted a dynamic observation of the cardiac damage caused by short- and long-term exposure to polystyrene nanoplastics (PS-NPs). Oxidative stress, inflammation, disruption of calcium ion homeostasis, and mitochondrial dysfunction were confirmed as the potential mechanisms of PS-NP-induced cardiotoxicity and the crucial events in the early stages, while cardiac fibrosis emerged as a prominent feature in late stages. Notably, low-dose exposure exacerbated myocardial infarction symptoms under pathological states, despite no significant cardiotoxicity shown in healthy models. In conclusion, these findings further deepened our understanding of PS-NP-induced cardiotoxic effects and introduced a promising in vitro platform for assessing cardiotoxicity.

Due to their good wearability, smart fabrics have gradually developed into one of the important components of multifunctional flexible electronics. Nevertheless, function integration is typically accomplished through the intricate stacking of diverse modules, which inevitably compromises comfort and elevates processing complexities. The integration of these discrete functional modules into a unified design for smart fabrics represents a superior solution. Here, we put forward a rational approach to functional integration for the typical challenges of thermal management, energy supply, and surface contamination in smart fabrics. This sandwich-structured multilayer fabric (MLF) is obtained by continuous electrospinning of two layer P(VDF-HFP) fabric and one layer P(VDF-HFP) fabric functionalized with core-shell SiO₂/ZnO/ZIF-8 (SZZ) nanoparticles. Specifically, MLFs achieve effective and stable energy harvesting in triboelectric nanogenerators (TENGs) with hydrophobicity and antibacterial properties. Meanwhile, MLFs also have high mid-infrared emissivity and sunlight reflectivity, successfully realizing radiative cooling under different climates, and have been applied in wearing clothing, roof shading, and car covers. This work may contribute to the design and manufacturing of next-generation thermal comfort smart fabrics and wearable electronics, particularly in terms of the rational design of multifunctional devices.

Spin-helical Dirac Fermions at a doped topological insulator's boundaries can support Majorana quasiparticles when coupled with s-wave superconductors, but in n-doped systems, the requisite induced Cooper pairing in topological states is often buried at heterointerfaces or complicated by degenerate coupling with bulk conduction carriers. Rarely probed are p-doped topological structures with nondegenerate Dirac and bulk valence bands at the Fermi level, which may foster long-range superconductivity without sacrificing Majorana physics. Using ultrahigh-resolution photoemission, we report proximity pairing with a large decay length in p-doped topological Sb₂Te₃ on superconducting Nb. Despite no momentum-space degeneracy, the topological and bulk states of Sb₂Te₃/Nb exhibit the same isotropic superconducting gaps at low temperatures. Our results unify principles for realizing accessible pairing in Dirac Fermions relevant to topological superconductivity.

Hypoxia is one of the most typical features among various types of solid tumors, which creates an immunosuppressive tumor microenvironment (TME) and limits the efficacy of cancer treatment. Alleviating hypoxia becomes a key strategy to reshape hypoxic TME which improves cancer immunotherapy. However, it remains challenging to perform tumor precision therapy with controllable switches through hypoxia-activated gene editing and prodrugs to alleviate hypoxia. In this study, silica-coated second near-infrared window (NIR-II) emitting silver sulfide quantum dots are used as the carrier to load the Clustered Regularly Interspaced Short Palindromic Repeats/Cas9 (CRISPR/Cas9) system to target hypoxia-inducible factor-1 (HIF-1α) and guide tumor-targeted imaging. To reduce the off-target effects in nontumor cells and better control safety risks, a TME-triggered cascade-activation nanodiagnostic and therapeutic platform (AA@Cas-H@HTS) is designed, which achieves the hypoxia activation of prodrug tirapazamine (TPZ) and spatiotemporal release of CRISPR/Cas9 ribonucleoprotein. Tumor hypoxia is greatly alleviated by the synergistic function of HIF-1α depletion by gene editing and TPZ activation. Importantly, targeting HIF-1α disrupts the programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) signaling pathway, which effectively reshapes the immune-suppressive TME and activates T cell-mediated antitumor immunity. Taken together, we have provided a TME-triggered cascade-activation nanoplatform to alleviate hypoxia for improved cancer immunotherapy.

The phenotype of circulating tumor cells (CTCs) offers valuable insights into monitoring cancer metastasis and recurrence. While microfluidics presents a promising approach for capturing these rare cells in blood, the phenotypic profiling of CTCs remains technically challenging. Herein, we developed a nanoporous micropillar array chip enabling highly efficient capture and in situ phenotypic analysis of CTCs through enhanced and tunable on-chip immunoaffinity binding. The nanoporous micropillar array addresses the fundamental limits in fluidic mass transfer, surface stagnant flow boundary effect, and interface topographic and multivalent reactions simultaneously within a single device, resulting in a synergistic enhancement of CTC immunocapture efficiency. The CTC capture efficiency increased by approximately 40% for cancer cells with low surface marker expressing. By manipulating fluidic velocity (hydrodynamic drag force) on the chip, a cell adhesion gradient was generated in the capture chamber, enabling individual CTCs with varying expression levels of epithelial cellular adhesion molecules to be immunocaptured at the corresponding spatial locations where equilibrium drag force is provided. The clinical utility of the nanoporous micropillar array was demonstrated by accurately distinguishing early and advanced stages of breast cancer and further longitudinally monitoring treatment response. We envision that the nanoporous micropillar array chip will provide an in situ capture and molecular profiling approach for CTCs and enhance the clinical application of CTC liquid biopsy.

Understanding the influence of precursor pressures is crucial for optimizing the properties of MoS₂ grown through the chemical vapor deposition (CVD) process. In this study, we use kinetic Monte Carlo (KMC) simulations to investigate how varying the pressures of molybdenum (P_Mo) and sulfur (P_S) impacts the structural properties of MoS₂, such as grain shape and edge configurations. The simulations differentiate three distinct regimes─growth, steady-state, and etching─each defined by specific P_Mo, P_S, and the most probable atomic sites for filling or etching. We further explore how these regimes influence the atomic configuration of MoS₂, particularly the formation of different edge structures like sulfur zigzag (ZZ_S), molybdenum zigzag (ZZ_Mo), and their respective derivatives. A pressure diagram based on the equations of state and most probable atomic sites was constructed for each regime and validated by comparing predicted ZZ-derived edges to experimental observations. Additionally, the study examines the impact of etching on various line defects, providing insights into the evolution of the MoS₂ edges during the CVD process. These findings underscore the importance of controlling both growth and cessation phases in the CVD process to customize edge configurations, with significant implications for chemical functionalization, catalysis, and the electronic properties of transition metal dichalcogenides.