ACS Applied Nano Materials最新文献

Last decade has witnessed impressive progress in the fields of medicine and bioengineering with the aid of nanomaterials. Nanomaterials are favoured for their improved bio-chemical as well as mechanical properties with tremendous applications in biomedical domains such as disease diagnosis, targeted drug delivery, medical imaging, in vitro diagnostics, designing innovatory cross-functional implants and regenerative tissue engineering. The current situation insists upon crafting nanotools that are capable of catering to biological needs and construct more efficient biomedical strategies. In the recent years, surface functionalization and capping with biomolecules has initiated substantial interest towards research. In this regard, search of suitable biofunctionalized nanoparticles seem to be like finding pearls from ocean. Conjugating biological molecules with inorganic materials has paved the way for unravelling innovative functional materials with dramatically improved properties and a wide range of uses. Inorganic nanoparticles such as metals, metal oxides, as well as quantum dots have been hybridised or conjugated with biomolecules such as proteins, peptides, carbohydrates, and nucleic acids. The present review reports on various biomolecule functionalized inorganic nanomaterials highlighting the biomolecule-inorganic nanoparticle interaction studies, the mechanism of functionalization, antimicrobial efficacy of the functionalised nanoconjugates and its use in various biomedical applications.

High-grade serous ovarian cancer (HG-SOC), accounting for 70-80% of ovarian cancer deaths, is characterized by a widespread and rapid metastatic nature, influenced by diverse cell types, cell-cell interactions, and acellular components of the tumour microenvironment (TME). Within this tumour type, autocrine and paracrine activation of the endothelin-1 receptors (ET-1R), expressed in tumour cells and stromal elements, drives metastatic progression. The lack of three-dimensional models that faithfully recapitulate the unique HG-SOC TME has been the bottleneck in performing drug screening for personalized medicine. Herein, we developed HG-SOC tumouroids by engineering a dense central artificial cancer mass (ACM) containing HG-SOC cells, nested within a compressed hydrogel recapitulating the stromal compartment comprising type I collagen, laminin, fibronectin, and stromal cells (fibroblasts and endothelial cells). ET-1-stimulated HG-SOC cells in the tumouroids showed an altered migration pattern and formed cellular aggregates, mimicking micrometastases that invaded the stroma. Compared with control cells, ET-1-stimulated tumouroids showed a higher number of invasive bodies, which were reduced by treatment with the dual ET-1 receptor (ET-1R) antagonist macitentan. In addition, ET-1 increased the size of the invading aggregates compared with control cells. This study establishes an experimental 3D multicellular model eligible for mechanical research, investigating the impact of matrix stiffness and TME interactions, which will aid drug screening to guide therapeutic decisions in HG-SOC patients.

A light-responsive covalent-organic framework (COF) nanozyme, which integrates the advantages of the COF structure and light-stimulated nanozyme catalysis, is a class of sensing star materials with wide application prospects. However, the sensing methods based on light-responsive COF nanozymes are relatively single at present. Therefore, it is necessary to develop new sensing strategies to broaden its application in chemical sensing and achieve highly efficient detection. Here, a Cu²⁺-modified COF composite material (TpDA-Cu) was rationally designed. The addition of Cu significantly inhibits the excellent light-responsive nanozyme activity of TpDA itself. However, because of the restoration of the enzyme activity by thiram (Tr) and the oxidase mimic activity of the newly formed Cu/Tr complex, TpDA-Cu/Tr exhibits stronger light-responsive nanozyme activity. Enzyme kinetic data show that compared with TpDA, TpDA-Cu/Tr has a larger V_max value, which can achieve efficient catalytic oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). In addition, the strong coordination effect of Tr and TpDA-Cu also plays a key role in achieving ultrafast, sensitive, and selective colorimetric detection of Tr. This work develops a dual activity regulation strategy of light-responsive COF nanozymes based on analyte induction and provides a new perspective for the application of light-responsive COF nanozymes in the field of sensing.

There is a potential synergistic effect between nonsteroidal anti-inflammatory drugs and hydrogen sulfide (H₂S), but direct evidence for the study is lacking. With a single fluorescence detection method, it is difficult to accurately confirm the effectiveness of the synergistic effect. In this study, the fluorescent probe and the nonsteroidal anti-inflammatory drug naproxen were combined via different self-immolative spacer groups to obtain a diagnostic and therapeutic integrated fluorescent probe Nap-NP-NSB, which can release H₂S. The quantitative release of H₂S by Nap-NP-NSB was evaluated in vitro and in cells, and the synergistic effect of H₂S and naproxen was confirmed by monitoring the treatment process of cellular inflammation and oxidative damage of gastric mucosa cells. Finally, in vivo fluorescence imaging and mass spectrometry imaging of the liver and stomach tissues and their sections were performed in the mouse model of acute hepatitis. The dual-modal detection method not only confirmed that Nap-NP-NSB had better anti-inflammatory activity and less gastric mucosal damage, but also enabled a more accurate visualization of the drug synergistic effect of naproxen and H₂S. This work provides a dual visualization imaging method combining fluorescence and mass spectrometry imaging and develops a new idea for studying drug synergies based on self-immolative structures.

Widespread concern over surface water pollution has led to interest in developing easy-to-use accurate tools for citizen-based measurements that provide high spatial and temporal resolution while maintaining accuracy. Excessive anthropogenic phosphate significantly contributes to global eutrophication and necessitates regular on-site phosphate monitoring in surface waters. Traditional instrumentation for quantifying phosphate is labor-intensive, expensive, and performed in laboratories. Existing on-site testing methods relying on phosphomolybdenum blue (PMB) have limited sensitivity and stability under ambient conditions. To overcome these limitations, a novel low-cost, rapid, and user-friendly sensor for citizen-led phosphate monitoring in surface water is introduced and demonstrated with a global sampling campaign. The fast-flow microfluidic device provides user-friendly operation, achieving an environmentally relevant limit of detection (LoD) of 190 ppb, which is near the EPA-recommended maximum for phosphate. The dip-and-read operation reduces procedural steps while delivering accurate sample volume, making it well-suited for citizen-led science initiatives. This sensor exhibits high selectivity and prolonged stability for two months under ambient conditions. The sensor's performance was validated using the industry-standard UV-Vis method with 90% correlation. More than 1000 sensors were deployed in different continents, facilitating phosphate mapping in diverse water sources across multiple continents. The initiative covered much of the globe, including Thailand, Nepal, Brazil, Chile, the USA, and Germany. In some cases, phosphate levels exceeded legislative guidelines by 100-fold. Through the collaboration of citizen scientists, we analyzed regional topography and socioeconomic practices near water sources, identifying potential sources that could contribute to eutrophication in these areas.

The rapid and accurate identification of pathogenic bacteria is crucial for combating the growing threat of antibiotic resistance, nosocomial infections, and food safety concerns. This study presents a novel and comprehensive comparison of two vibrational spectroscopic techniques - attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and a low-cost miniature near-infrared (NIR) spectrometer - for distinguishing Gram-positive and Gram-negative bacterial samples grown using the same stock media solution. This is the first report of NIR spectroscopy being applied to differentiate Gram-positive and Gram-negative bacteria, as well as the first direct comparison of ATR-FTIR and NIR for the combined multimodal analysis of clinical bacterial isolates. Using a data set of five Gram-positive and seven Gram-negative species and recording spectra in triplicate, the study employed advanced data fusion and multivariate analysis techniques to classify the spectra and facilitate NIR band assignment. 2D correlation analysis revealed strong positive correlations between key spectral markers identified in both modalities. Partial least-squares- and support vector machine discriminant analysis models were validated using a methodology based on 100 repeated random sampling of calibration and test sets. Models demonstrated that both the standalone ATR-FTIR and the combined ATR-FTIR/NIR approach achieved exceptional classification accuracy (>98%) in differentiating the two bacterial groups. Differences observed in the spectra were attributed to the distinct cell wall compositions of Gram-Positive and Gram-negative bacteria. Notably, the low-cost NIR technique also showed promising performance, with classification accuracy values above 90%. The findings highlight the potential of these rapid, noninvasive, and cost-effective vibrational spectroscopic techniques, particularly the NIR method, for point-of-care applications in clinical microbiology and food safety monitoring. The combination of ATR-FTIR and NIR data further enhances the robustness and reliability of bacterial identification, paving the way for broader adoption of these advanced analytical tools in various healthcare and food safety settings.

Heat shock seriously affects the normal functioning of an organism and can lead to damage and even death in severe cases. To prevent or treat heat shock-related diseases, we require a better understanding of the mechanism of thermocytotoxicity. Here, we designed a functionalized dual-response fluorescent probe (HCy-SO₂-HClO) that could individually or simultaneously detect hypochlorous acid (HClO) and sulfur dioxide (SO₂) without interfering with each other and achieved the simultaneous tracing of both during the heat shock process for the first time. The introduction of the sulfonate group greatly increased the water solubility of the probe. Furthermore, the probe could effectively accumulate in the mitochondrial region. HCy-SO₂-HClO could respond to HClO and SO₂ within 10 s and 20 min, respectively, realizing a double whammy detection of both on the time scale. HCy-SO₂-HClO exhibited high specificity and sensitivity for HClO and SO₂. The highly biocompatible probe HCy-SO₂-HClO successfully achieved the detection of endogenous and exogenous SO₂ and HClO in living cells and in zebrafish. Moreover, the simultaneous detection of HClO and SO₂ in heat shock cells and mouse intestines was realized for the first time. This probe has achieved the detection of dual markers, which enhanced the accuracy and precision of disease detection and could serve as an effective research tool to prevent heat stroke-related diseases.

DNA walkers have emerged as a powerful tool in bioanalysis; however, many existing approaches are still restricted by low reaction kinetics and inaccurate single-mode detection. Herein, a fluorescence (FL) and electrochemical (EC) dual-mode biosensor was proposed based on a multispatially localized DNA walker (m-DNA walker) coupling covalent organic framework (COF) using the walking-recycling-conversion strategy. Specifically, the functionalized COF not only served as a three-dimensional nanocarrier but also acted as an effective quencher of the walking tracks. In the presence of the target, the activated m-DNA walker moved fast along the numerous quenching tracks, leading to the cleavage of Cy3-H1 and the recovery of the FL signal. To further improve the detection sensitivity, the Cy3-H1 fragments' recycling process was implemented with the generation of a large amount of S1 and S2, which caused the assembly of DNA-Fe³⁺-polydopamine network amplifiers on the electrode. The rapid electrochemical conversion was introduced to convert DNA-Fe³⁺-polydopamine into electroactive Prussian Blue, providing a significant EC signal output. Using nucleocapsid protein (N-protein) as the model target, the designed biosensing platform produced a FL/EC dual-mode readout with the detection limits of 65.0 fg/mL for FL mode and 2.3 fg/mL for EC mode, which could eliminate the interference from different reactive pathways and improve the detection accuracy, holding potential application in early disease diagnosis and treatment.

Mitochondria play a pivotal role in maintaining normal physiological functions. Mitochondrial autophagy, namely, mitophagy, is a selective catabolic disposal of impaired mitochondria through an autophagic mechanism during episodes of mitochondrial harm. This selective removal, e.g., mitophagy, is essential for mitochondrial quality control and is closely related to the pathogenesis of many diseases. The abnormal buildup of defective mitochondria in vivo was used as a target to prevent the development of cancer. The mitochondrial autophagy process of disease-related cells is usually accompanied by a decrease in polarity and pH, and the fluorescence sensing effects caused by these two factors are usually contradictory. Here, we propose a reinventing strategy to develop a dual-channel and dual-responsive fluorescent probe HDTVB that is capable of tracking mitochondrial autophagy by monitoring fluctuations in mitochondrial pH and polarity. Based on the aggregation-induced emission (AIE) moiety and hemicarpine moiety push-pull system with activated near-infrared (NIR) emission and pH-activatable cyclization reaction, HDTVB was able to differentiate tumors from normal sites via polarity- and acidity-triggered structural changes of the probe in the course of mitochondrial autophagy. HDTVB is expected to be applied to clinical diagnosis and tumor excision guided by fluorescence, offering a new route in physiological and biochemical research.

Uneven energy distribution of femtosecond lasers presents a significant challenge for single-spot analysis, which often leads to concave ablation craters. This study assesses the performance of a femtosecond laser ablation system for in situ analysis using novel galvanometer scanners. A galvanometer rapidly moved the laser beam focus to create craters with a small beam spot. We first examined the inductively coupled plasma mass spectrometry (ICP-MS) signal sensitivity to laser parameters, establishing a strong linear correlation with the laser energy, repetition rate, scanning ablation area, and galvanometer scanning frequency. Elemental fractionation analysis of NIST SRM 610 suggests minimal bias, with fractionation indices of different elements approaching unity. Subsequently, the elemental concentration of six reference material glasses was measured by fsLA-ICP-MS to evaluate the elemental quantification capabilities of the Galvo-femtosecond laser (Galvo-fsLA). The laser's capability for in situ U-Pb dating was demonstrated by concordant U-Pb ages of five zircon reference materials that are highly consistent with the ID-TIMS ages reported previously. Finally, the reliability of the new Galvo-fsLA for isotope analysis was verified by the accurate determination of radiogenic Hf, Pb isotopes, and stable Cu isotopes, all agreeing well with their reference values within uncertainties. These assessments underscore the significant potential of Galvo-fsLA for enhanced accuracy and precision of single-spot in situ analysis.