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1.
J Environ Sci (China) ; 148: 139-150, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095153

RESUMEN

Herein, a modified screen printed carbon electrode (SPCE) based on a composite material, graphene oxide-gold nanoparticles (GO-AuNPs), and poly(3-aminobenzoic acid)(P3ABA) for the detection of paraquat (PQ) is introduced. The modified electrode was fabricated by drop casting of the GO-AuNPs, followed by electropolymerization of 3-aminobenzoic acid to achieve SPCE/GO-AuNPs/P3ABA. The morphology and microstructural characteristics of the modified electrodes were revealed by scanning electron microscopy (SEM) for each step of modification. The composite GO-AuNPs can provide high surface area and enhance electroconductivity of the electrode. In addition, the presence of negatively charged P3ABA notably improved PQ adsorption and electron transfer rate, which stimulate redox reaction on the modified electrode, thus improving the sensitivity of PQ analysis. The SPCE/GO-AuNPs/P3ABA offered a wide linear range of PQ determination (10-9-10-4 mol/L) and low limit of detection (LOD) of 0.45 × 10-9 mol/L or 0.116 µg/L, which is far below international safety regulations. The modified electrode showed minimum interference effect with percent recovery ranging from 96.5% to 116.1% after addition of other herbicides, pesticides, metal ions, and additives. The stability of the SPCE/GO-AuNPs/P3ABA was evaluated, and the results indicated negligible changes in the detection signal over 9 weeks. Moreover, this modified electrode was successfully implemented for PQ analysis in both natural and tapped water with high accuracy.


Asunto(s)
Técnicas Electroquímicas , Electrodos , Oro , Grafito , Nanopartículas del Metal , Paraquat , Grafito/química , Paraquat/análisis , Oro/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Límite de Detección , Carbono/química , Contaminantes Químicos del Agua/análisis , Herbicidas/análisis
2.
Sensors (Basel) ; 24(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39275446

RESUMEN

Particle plasmon resonance (PPR), or localized surface plasmon resonance (LSPR), utilizes intrinsic resonance in metal nanoparticles for sensor fabrication. While diffraction grating waveguides monitor bioaffinity adsorption with out-of-plane illumination, integrating them with PPR for biomolecular detection schemes remains underexplored. This study introduces a label-free biosensing platform integrating PPR with a diffraction grating waveguide. Gold nanoparticles are immobilized on a glass slide in contact with a sample, while a UV-assisted embossed diffraction grating is positioned opposite. The setup utilizes diffraction in reflection to detect changes in the environment's refractive index, indicating biomolecular binding at the gold nanoparticle surface. The positional shift of the diffracted beam, measured with varying refractive indices of sucrose solutions, shows a sensitivity of 0.97 mm/RIU at 8 cm from a position-sensitive detector, highlighting enhanced sensitivity due to PPR-diffraction coupling near the gold nanoparticle surface. Furthermore, the sensor achieved a resolution of 3.1 × 10-4 refractive index unit and a detection limit of 4.4 pM for detection of anti-DNP. The sensitivity of the diffracted spot was confirmed using finite element method (FEM) simulations in COMSOL Multiphysics. This study presents a significant advancement in biosensing technology, offering practical solutions for sensitive, rapid, and label-free biomolecule detection.


Asunto(s)
Técnicas Biosensibles , Oro , Nanopartículas del Metal , Resonancia por Plasmón de Superficie , Resonancia por Plasmón de Superficie/métodos , Oro/química , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Refractometría , Análisis de Elementos Finitos , Límite de Detección
3.
Artículo en Inglés | MEDLINE | ID: mdl-39285705

RESUMEN

Artificial intelligence and human-computer interaction advances demand bioinspired sensing modalities capable of comprehending human affective states and speech. However, endowing skin-like interfaces with such intricate perception abilities remains challenging. Here, we have developed a flexible piezoresistive artificial ear (AE) sensor based on gold nanoparticles, which can convert sound signals into electrical signals through changes in resistance. By testing the sensor's performance at both frequency and sound pressure level (SPL), the AE has a frequency response range of 20 Hz to 12 kHz and can sense sound signals from up to 5 m away at a frequency of 1 kHz and an SPL of 126 dB. Furthermore, through deep learning, the device achieves up to 96.9% and 95.0% accuracy in classification and recognition applications for seven emotional and eight urban environmental noises, respectively. Hence, on one hand, our device can monitor the patient's emotional state by their speech, such as sudden yelling and screaming, which can help healthcare workers understand patients' condition in time. On the other hand, the device could also be used for real-time monitoring of noise levels in aircraft, ships, factories, and other high-decibel equipment and environments.

4.
J Taibah Univ Med Sci ; 19(4): 901-909, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39280190

RESUMEN

Objective: This study aimed to assess the cytotoxic effects of an extract from Pelargonium graveolens leaves and green-synthesized gold nanoparticles (AuNPs) in a mouthwash when used as a substitute for commercial mouthwashes. Human dermal fibroblasts from neonates (HDFn) were used in this study that done in vitro, because their characteristics were nearly identical to those of human gingival fibroblasts. Method: In this study, the green synthesis of AuNPs using extracts from P. graveolens leaves was investigated as a sustainable and economical method. Then, using a range of analytical techniques, the physicochemical properties were evaluated, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), and ultraviolet visible absorption spectroscopy (UV-Vis), so the preparations and analytical techniques of P. graveolens gold nanoparticles (AuNPs) take little time is about 10 days. The current study used the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl-tetrazolium bromide Mosmann's Tetrazolium Toxicity (MTT) to study the cytotoxic effects of P. graveolens leaf extract with P. graveolens gold nanoparticles (AuNPs) utilizing a human fibroblast-derived standard cell line. Results: Various doses (1000, 500, 250, 100, 50, 25, 12.5, 6.25, and 3.125 µg/mL) of P. graveolens AuNPs were used to assess cytotoxicity, demonstrating little cytotoxic effects (approximately below 20% toxicity). A high level of biocompatibility was observed between the P. graveolens AuNPs and normal human fibroblasts. Conclusion: The mouthwash made using green synthetic AuNPs obtained from P. graveolens leaf extract show high level of biocompatibility and has low cytotoxicity. Therefore, herbal mouthwash formulations can serve as a viable substitute for chemical mouthwashes.

5.
Anal Chim Acta ; 1326: 343094, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39260911

RESUMEN

In response to the growing demand for biomolecular diagnostics, metasurface (MS) platforms based on high-Q resonators have demonstrated their capability to detect analytes with smart data processing and image analysis technologies. However, high-Q resonator meta-atom arrays are highly sensitive to the fabrication process and chemical surface functionalization. Thus, spectrum scanning systems are required to monitor the resonant wavelength changes at every step, from fabrication to practical sensing. In this study, we propose an innovative dielectric resonator-independent MS platform that enables spectrometer-less biomolecule detection using artificial intelligence (AI) at a visible wavelength. Functionalizing the focused vortex MS to capture gold nanoparticle (AuNP)-based sandwich immunoassays causes the resulting vortex beam profiles to be significantly affected by the localized surface plasmon resonance (LSPR) occurring between AuNPs and meta-atoms. The convolutional neural network algorithm was carefully trained to accurately classify the AuNP concentration-dependent focused vortex beam, facilitating the determination of the concentration of the targeted diagnostic biomolecule. Successful in situ identification of various biomolecule concentrations was achieved with over 99 % accuracy, indicating the potential of combining an LSPR-susceptible MS platform and AI for continuously tracking various chemical and biological compounds.


Asunto(s)
Inteligencia Artificial , Oro , Nanopartículas del Metal , Resonancia por Plasmón de Superficie , Oro/química , Nanopartículas del Metal/química , Resonancia por Plasmón de Superficie/métodos , Humanos , Inmunoensayo/métodos , Redes Neurales de la Computación , Técnicas Biosensibles/métodos
6.
Nanomaterials (Basel) ; 14(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39269061

RESUMEN

In observing the electrocatalytic current of nanoparticles (NPs) using single-entity electrochemistry (SEE), the surface state of the NPs significantly influences the SEE signal. This study investigates the influence of capping agents on the electrocatalytic properties of gold (Au) NPs using SEE. Two inner-sphere reactions, hydrazine oxidation and glucose oxidation, were chosen to explore the SEE characteristics of Au NPs based on the capping agent presence. The results revealed that "capping agent-free" Au NPs exhibited signal magnitudes and frequencies consistent with theoretical expectations, indicating superior stability and catalytic performance in electrolyte solutions. In contrast, citrate-capped Au NPs showed signals varying depending on the applied potential, with larger magnitudes and lower frequencies than expected, likely due to an aggregation of NPs. This study suggests that capping agents play a crucial role in the catalytic performance and stability of Au NPs in SEE. By demonstrating that minimizing capping agent presence can enhance effectiveness in SEE, it provides insights into the future applications of NPs, particularly highlighting their potential as nanocatalysts in energy conversion reactions and environmental applications.

7.
Nano Lett ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231360

RESUMEN

Optical forces enable noncontact manipulation of micro- and nanoscale objects, offering diverse applications. When a laser beam irradiates multiple nanoparticles in a solvent, it induces the formation of an ordered array with a finite distance between particles due to optical binding, which results from the optical force exerted by scattered light. This scattered light extends beyond the irradiation area, facilitating interactions between spatially separated nanoparticle assemblies under multiple laser beams. However, the extension of optical binding in this context remains underexplored. In this study, we propose a concept of generalized optical binding between particle assemblies using two focal laser beams. Under carefully designed conditions, the scattered light between assemblies leads the particles to stable positions and impedes rotational dynamics driven by the circular polarization of the lasers. We demonstrate the fusion and reordering of two hexagonal assemblies, offering a blueprint for creating on-demand particle arrays through laser beam manipulation.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39253872

RESUMEN

Recent advancements in flexible electronics have highlighted their potential in biomedical applications, primarily due to their human-friendly nature. This study introduces a new flexible electronic system designed for motion sensing in a biomimetic three-dimensional (3D) environment. The system features a self-healing gel matrix (chitosan-based hydrogel) that effectively mimics the dynamics of the extracellular matrix (ECM), and is integrated with a highly sensitive thin-film resistive strain sensor, which is fabricated by incorporating a cross-linked gold nanoparticle (GNP) thin film as the active conductive layer onto a biocompatible microphase-separated polyurethane (PU) substrate through a clean, rapid, and high-precision contact printing method. The GNP-PU strain sensor demonstrates high sensitivity (a gauge factor of ∼50), good stability, and waterproofing properties. The feasibility of detecting small motion was evaluated by sensing the beating of human induced pluripotent stem cell (hiPSC)-derived cardiomyocyte spheroids embedded in the gel matrix. The integration of these components exemplifies a proof-of-concept for using flexible electronics comprising self-healing hydrogel and thin-film nanogold in cardiac sensing and offers promising insights into the development of next-generation biomimetic flexible electronic devices.

9.
Water Res X ; 24: 100239, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39193396

RESUMEN

Per- and polyfluoroalkyl substances (PFASs) are emerging contaminants detected ubiquitously and have negative impacts on human health and ecosystem; thus, developing in-situ sensing technique is important to ensure safety. Herein, we report a novel colorimetric-based sensor with perfluoroalkyl receptor attached to citrate coated gold nanoparticles (Citrate-Au NPs) that can detect several PFASs including perfluorocarboxylates with different chain lengths (PFHxA, PFOA, PFNA, PFDA), perfluorooctanoic sulfonate (PFOS), and perfluorooctanoic phosphonate (PFOPA). The sensor detects PFASs utilizing fluorous interaction between PFASs and the perfluoroalkyl receptor of Citrate-Au NPs in a solution at a fixed salt concentration, inducing changes in nanoparticle dispersity and the solution color. The rate of spectrum shift was linearly dependent on PFASs concentrations. Citrate-Au NPs with size between 29 - 109 nm were synthesized by adjusting citrate/Au molar ratios, and 78 nm showed the best sensitivity to PFOA concentration (with level of detection of 4.96 µM). Citrate-Au NPs only interacted with PFASs with perfluoroalkyl length > 4 and not with non-fluorinated alkyl compound (nonanoic acid). The performance of Citrate-Au NP based sensor was strongly dependent on the chain length of the perfluoroalkyl group and the head functional group; higher sensitivity was observed with longer chain over shorter chain, and with sulfonate functional group over carboxylate and phosphonate. The sensor was tested using real water samples (i.e., tap water, filtered river water), and it was found that the sensor is capable of detecting PFASs in these conditions if calibrated with the corresponding water matrix. While further optimization is needed, this study demonstrated new capability of Citrate-Au NPs based sensor for detection of PFASs in water.

10.
J Pharm Sci ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39151794

RESUMEN

The basis of most neurological syndromes is the accumulation of free radical molecules. Quercetin is a polyphenolic bioflavonoid molecule and it has a very strong antioxidant effect by maintaining oxidative balance. There are many difficulties in the clinical use of quercetin due to its hydrophobic structure, low solubility, instability, poor oral bioavailability, and limited tissue-barrier penetration. Its synergistic use in complex with gold nanoparticles (AuNPs) could overcome these problems. AuNPs have recently emerged as an attractive candidate for delivery applications of various biomolecules and drugs. The aim of this study was to synthesize two different sized gold nanoparticles (AuNP20 and AuNP50) modified with polyethyleneimine (PEI) and quercetin, evaluate their potential neuroprotective effects on the in vitro oxidative stress model using DRG primary sensory neurons. It was shown that the antioxidant and anti-apoptotic ability of the bioflavonoid was preserved after exposure to the designed quercetin modified AuNPs. The PEI surface coating increased the stability and biocompatibility of the AuNPs in both sizes. It also potentially enables additional surface functionalization. This study indicates that designed nanoparticles (AuNP-Q-PEI) with different sizes could be a useful potential platform for the treatment of neurodegenerative syndromes or cancer diseases.

11.
ACS Sens ; 9(8): 4207-4215, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39088458

RESUMEN

ß-Thalassemia is a prevalent type of severe inherited chronic anemia, primarily identified in developing countries. The identification of single nucleotide polymorphisms (SNPs) plays a vital role in the early diagnosis of genetic diseases. Here, we reported the development of an amplification-free fiber optic nanogold-linked sorbent assay method using a fiber optic particle plasmon resonance (FOPPR) biosensor for rapid and ultrasensitive detection of SNPs. Herein, MutS protein was selected as the biorecognition capture probe and immobilized on the sensing region to capture the target mutant DNA, which was hybridized with a single-base mismatched single-stranded DNA labeled by a gold nanoparticle (AuNP). The AuNP acts as a signaling agent to be detected by the FOPPR biosensor when it is bound on the fiber core surface. The method effectively differentiates mismatched double-stranded DNA by MutS protein from perfectly matched/complementary dsDNA. It exhibits an impressively low detection limit for the detection of SNPs at approximately 10-16 M using low-cost sensor chips and devices. By determination of the ratio of mutant DNA to normal DNA in cell-free genomic DNA from blood samples, this method is promising for diagnosing ß-thalassemia in fetuses without invasive testing techniques.


Asunto(s)
Ácidos Nucleicos Libres de Células , Oro , Nanopartículas del Metal , Polimorfismo de Nucleótido Simple , Talasemia beta , Talasemia beta/diagnóstico , Talasemia beta/genética , Talasemia beta/sangre , Humanos , Oro/química , Nanopartículas del Metal/química , Ácidos Nucleicos Libres de Células/sangre , Diagnóstico Prenatal/métodos , Tecnología de Fibra Óptica , Pruebas Genéticas/métodos , Técnicas Biosensibles/métodos , Embarazo , Femenino , Límite de Detección , Resonancia por Plasmón de Superficie/métodos
12.
ACS Appl Bio Mater ; 7(9): 6239-6248, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39155492

RESUMEN

Leishmaniasis, attributed to the protozoan parasite Leishmania, manifests in diverse clinical forms, including cutaneous, mucocutaneous, and visceral leishmaniasis; VL constitutes a significant global health menace. Prevalent in tropical and subtropical regions, this affliction disproportionately impacts individuals below the poverty threshold, transmitted through the bite of female sandflies. Existing treatments, such as pentavalent antimony, miltefosine, and Amphotericin B, exhibit limitations. Despite the emergence of liposomal Amphotericin B (AmBisome) as a promising antileishmanial agent, its utility is impeded by adverse effects, elevated production expenses, and cytotoxicity. To address these challenges, our investigation introduces a potential remedy─a citrate-coated gold Amphotericin B nanoparticle formulation. Characterized using dynamic light scattering and transmission electron microscopy, this pioneering formulation exhibited efficacy against L. donovani Ag83 promastigotes as demonstrated by MTT cell viability testing. Evaluating internal reactive oxygen species (ROS) levels and dual staining with acridine orange and ethidium bromide unveiled its consequential impact on cell death. Significantly, our study discloses this novel nanoformulation's unprecedented inhibition of the trypanothione reductase enzyme. The findings posit the citrate-coated gold Amphotericin B nanoformulation as a promising and targeted antileishmanial agent, representing potential advancements in leishmaniasis therapeutics.


Asunto(s)
Anfotericina B , Antiprotozoarios , Oro , Nanopartículas del Metal , Oro/química , Oro/farmacología , Anfotericina B/farmacología , Anfotericina B/química , Antiprotozoarios/farmacología , Antiprotozoarios/química , Antiprotozoarios/síntesis química , Nanopartículas del Metal/química , Tamaño de la Partícula , Nanoconjugados/química , Ensayo de Materiales , Leishmania donovani/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Supervivencia Celular/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Especies Reactivas de Oxígeno/metabolismo , Humanos
13.
J Control Release ; 373: 652-666, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39089503

RESUMEN

Androgenetic alopecia (AGA) is a non-fatal disease prevalent worldwide. However, mixed efficacy has been observed among different therapies for hair regrowth in AGA patients. Thus, a nano-platform with synergistic treatments based on a hybrid extracellular vesicle encapsulating gold nanoparticles (AuNPs) and finasteride (Hybrid/Au@Fi) was constructed through membrane fusion between hair follicle stem cell (HFSC)-derived extracellular vesicles and liposomes. These hybrid vesicles (HVs) not only fuel hair regrowth by providing cellular signals in extracellular vesicles, but also improve storage stability, follicle retention, and drug encapsulation efficiency (EE%) for finasteride inhibiting 5α-reductase, and nano-size AuNPs that simulate low-level laser therapy (LLLT) with similar photothermal effects in vitro. The EE% of finasteride in these HVs reached 45.33%. The dual administration of these extracellular vesicles and finasteride showed a strong synergistic effect on HFSCs in vitro. In an AGA mouse model, once-daily topical Hybrid/Au@Fi (115.07 ± 0.32 nm, -7.50 ± 1.68 mV) gel led to a faster transition of hair follicles (HFs) from the catagen to the anagen, increased hair regrowth coverage, and higher quality of regrowth hair, compared to once-daily 5% minoxidil treatment. Compared to topical minoxidil, the multifaceted synergistic therapy of Hybrid/Au@Fi through topical administration offers a new option for intractable AGA patients with low side effects.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Alopecia , Vesículas Extracelulares , Finasterida , Oro , Folículo Piloso , Nanopartículas del Metal , Células Madre , Finasterida/administración & dosificación , Oro/química , Oro/administración & dosificación , Alopecia/terapia , Animales , Nanopartículas del Metal/administración & dosificación , Células Madre/citología , Inhibidores de 5-alfa-Reductasa/administración & dosificación , Humanos , Liposomas , Masculino , Ratones , Ratones Endogámicos C57BL , Cabello/crecimiento & desarrollo
14.
ACS Appl Bio Mater ; 7(9): 6127-6137, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39133870

RESUMEN

Rapid detection and classification of pathogenic microbes for food hygiene, healthcare, environmental contamination, and chemical and biological exposures remain a major challenge due to nonavailability of fast and accurate detection methods. The delay in clinical diagnosis of the most frequent bacterial infections, particularly urinary tract infections (UTIs), which affect about half of the population at least once in their lifetime, can be fatal if not detected and treated appropriately. In this work, we have fabricated aluminum (Al) foil integrated pegylated gold nanoparticles (AuNPs) as a potential surface-enhanced Raman scattering (SERS) substrate, which is used for the detection and classification of uropathogens, namely, E. coli, S. aureus, and P. aeruginosa directly from the culture without any pretreatment. The substrate is first drop cast with bacterial pellets and then pegylated AuNPs, and the interaction of two on Al foil base gives identifiable characteristic Raman peaks with good reproducibility. With the use of chemometric methods such as principal component analysis (PCA), the Al foil-based SERS substrate offers a quick, effective detection and classification of three strains of UTI bacteria with the least bacterial concentration (105 cells mL-1) necessary for clinical diagnosis. In addition, this substrate was able to detect E. coli positive clinical samples by giving SERS fingerprint information directly from centrifuged urine samples within minutes. The stability of pegylated AuNPs provides for its application at the point of care with rapid and easy detection of uropathogens as well as the possibility of advancement in healthcare applications.


Asunto(s)
Aluminio , Escherichia coli , Oro , Nanopartículas del Metal , Polietilenglicoles , Espectrometría Raman , Staphylococcus aureus , Oro/química , Nanopartículas del Metal/química , Aluminio/química , Polietilenglicoles/química , Escherichia coli/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación , Tamaño de la Partícula , Propiedades de Superficie , Ensayo de Materiales , Materiales Biocompatibles/química , Pseudomonas aeruginosa/aislamiento & purificación , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/microbiología , Humanos
15.
Nano Lett ; 24(35): 11082-11089, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39171663

RESUMEN

Nanoparticle superlattices are beneficial in terms of providing strong and uniform signals in analysis owing to their closely packed uniform structures. However, nanoparticle superlattices are prone to cracking during physical activities because of stress concentrations, which hinders their detection performance and limits their analytical applications. In this work, template printing methods were used in this study to prepare a patterned gold nanoparticle (AuNP) superlattice film. By adjustment of the size of the AuNP superlattice domain below the critical size of fracture, the mechanical stability of the AuNP superlattice domain is improved. Thus, long-term sustainable high-performance signal output is achieved. The patterned AuNP superlattice film was used to construct a wearable sweat sensor based on surface-enhanced Raman scattering (SERS). The designed sensor showed promise for long-term reliable use in actual scenarios in terms of recommending water replenishment, monitoring hydration states, and tracking the intensity of activity.


Asunto(s)
Oro , Nanopartículas del Metal , Espectrometría Raman , Sudor , Dispositivos Electrónicos Vestibles , Oro/química , Nanopartículas del Metal/química , Sudor/química , Humanos , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Propiedades de Superficie
16.
Drug Dev Ind Pharm ; : 1-14, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39159138

RESUMEN

Lung cancer has become progressively widespread, posing a challenge to traditional chemotherapeutic drugs such as platinum compounds and paclitaxel (PTX) owing to growing resistance. Along with that, the chemotherapeutic drugs infer major side effects. The usage of natural compounds as chemosensitizers to boost the efficacy of these chemotherapeutic drugs and minimizing their toxicity is a plausible approach. In our investigation, we employed PTX as the standard chemotherapeutic agent and utilized chrysin-functionalized gold nanoparticles (CHR-AuNPs) to augment its cytotoxicity. Gold nanoparticles were chosen for their inherent cytotoxic properties and ability to enhance chrysin's bioavailability and solubility. Characterization of CHR-AuNP revealed spherical nanoparticles within the nano-size range (35-70 nm) with a stable negative zeta potential of -22 mV, confirmed by physicochemical analyses including UV-visible spectroscopy, Fourier transform infrared (FTIR) spectral analysis, and visual observation of the wine-red coloration. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay cytotoxicity studies demonstrated CHR-AuNP's superior efficacy compared to CHR alone, with synergistic effects observed in combination with PTX, validated by Compusyn software. Morphological changes indicative of apoptosis were more pronounced with combined treatment, corroborated by acridine orange/ethidium bromide (AO/EtBr) staining and Annexin V assays. Furthermore, the combination treatment amplified reactive oxygen species (ROS) production and destabilized mitochondrial membrane potential, while altering the expression of pro-apoptotic and anti-apoptotic proteins. Exploring the mechanistic pathways, we found that the drugs upregulated PPAR-γ expression while suppressing Akt and overexpressing PTEN, thereby impeding the Wnt/ß-catenin pathway commonly dysregulated in lung cancer. This highlights the potential of low-dose combination therapy with PTX and CHR-AuNP as a promising strategy for addressing lung cancer's challenges.

17.
Angew Chem Int Ed Engl ; : e202409283, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38962888

RESUMEN

Achieving electronic/steric control and realizing selectivity regulation in nanocatalysis remains a formidable challenge, as the dynamic nature of metal-ligand interfaces, including dissolution (metal leaching) and structural reconstruction, poses significant obstacles. Herein, we disclose carboranyls (CBs) as unprecedented carbon-bonded functional ligands (Eads.CB-Au(111)=-2.90 eV) for gold nanoparticles (AuNPs), showcasing their exceptional stabilization capability that is attributed by strong Au-C bonds combined with B-H⋅⋅⋅Au interactions. The synthesized CB@AuNPs exhibit core(Aun)-satellite(CB2Au-) structure, showing high stability towards multiple stimuli (110 °C, pH=1-12, thiol etchants). In addition, different from conventional AuNP catalysts such as triphenylphosphine (PPh3) stabilized AuNPs, dissolution of catalytically active gold species was suppressed in CB@AuNPs under the reaction conditions. Leveraging these distinct features, CB@AuNPs realized outstanding p : o selectivities in aromatic bromination. Unbiased arenes including chlorobenzene (up to >30 : 1), bromobenzene (15 : 1) and phenyl acrylate were examined using CB@AuNPs as catalysts to afford highly-selective p-products. Both carboranyl ligands and carboranyl derived counterions are crucial for such regioselective transformation. This work has provided valuable insights for AuNPs in realizing diverse regioselective transformations.

18.
Mikrochim Acta ; 191(8): 477, 2024 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039391

RESUMEN

A novel biofuel cell (BFC)-based self-powered electrochemical immunosensing platform was developed by integrating the target-induced biofuel release and biogate immunoassay for ultrasensitive 17ß-estradiol (E2) detection. The carbon nanocages/gold nanoparticle composite was employed in the BFCs device as the electrode material, through which bilirubin oxidase and glucose oxidase were wired to form the biocathode and bioanode, respectively. Positively charged mesoporous silica nanoparticles (PMSN) were encapsulated with glucose molecules as biofuel and subsequently coated by the negatively charged AuNPs-labelled anti-E2 antibody (AuNPs-Ab) serving as a biogate. The biogate could be opened efficiently and the trapped glucose released once the target E2 was recognized and captured by AuNPs-Ab due to the decreased adhesion between the antigen-antibody complex and PMSN. Then, glucose oxidase oxidized the glucose to produce a large number of electrons, resulting in significantly increased open-circuit voltage (EOCV). Promisingly, the proposed BFC-based self-powered immunosensor demonstrated exceptional sensitivity for the detection of E2 in the concentration range from 1.0 pg mL-1 to 10.0 ng mL -1, with a detection limit of 0.32 pg mL-1 (S/N = 3). Furthermore, the prepared BFC-based self-powered homogeneous immunosensor showed significant potential for implementation as a viable prototype for a mobile and an on-site bioassay system in food and environmental safety applications.


Asunto(s)
Fuentes de Energía Bioeléctrica , Técnicas Biosensibles , Estradiol , Glucosa Oxidasa , Oro , Límite de Detección , Nanopartículas del Metal , Inmunoensayo/métodos , Estradiol/química , Estradiol/análisis , Oro/química , Glucosa Oxidasa/química , Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Humanos , Electrodos , Glucosa/análisis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/química , Anticuerpos Inmovilizados/inmunología , Dióxido de Silicio/química , Enzimas Inmovilizadas/química
19.
Nano Lett ; 24(29): 8956-8963, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38984788

RESUMEN

Nanoparticle assemblies with interparticle ohmic contacts are crucial for nanodevice fabrication. Despite tremendous progress in DNA-programmable nanoparticle assemblies, seamlessly welding discrete components into welded continuous three-dimensional (3D) configurations remains challenging. Here, we introduce a single-stranded DNA-encoded strategy to customize welded metal nanostructures with tunable morphologies and plasmonic properties. We demonstrate the precise welding of gold nanoparticle assemblies into continuous metal nanostructures with interparticle ohmic contacts through chemical welding in solution. We find that the welded gold nanoparticle assemblies show a consistent morphology with welded efficiency over 90%, such as the rod-like, triangular, and tetrahedral metal nanostructures. Next, we show the versatility of this strategy by welding gold nanoparticle assemblies of varied sizes and shapes. Furthermore, the experiment and simulation show that the welded gold nanoparticle assemblies exhibit defined plasmonic coupling. This single-stranded DNA encoded welding system may provide a new route for accurately building functional plasmonic nanomaterials and devices.

20.
Antibiotics (Basel) ; 13(7)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39061312

RESUMEN

Inhaled colistin is used to treat pneumonia and respiratory infections through nebulization or dry powder inhalers. Nevertheless, the development of a metered-dose inhaler (MDI) for colistin, which could enhance patient convenience and treatment efficacy, has not yet been developed. Colistin is known for its ability to induce cellular toxicity. Gold nanoparticles (AuNPs) can potentially mitigate colistin toxicity. Therefore, this study aimed to evaluate the antimicrobial effectiveness of colistin conjugated with chitosan-capped gold nanoparticles (Col-CS-AuNPs) and their potential formulation for use with MDIs to deliver the aerosol directly to the deep lung. Fourier-transform infrared spectroscopy, nuclear magnetic resonance, and elemental analysis were used to characterize the synthesized Col-CS-AuNPs. Drug release profiles fitted with the most suitable release kinetic model were evaluated. An MDI formulation containing 100 µg of colistin per puff was prepared. The aerosol properties used to determine the MDI performance included the fine particle fraction, mass median aerodynamic diameter, and geometric standard deviation, which were evaluated using the Andersen Cascade Impactor. The delivered dose uniformity was also determined. The antimicrobial efficacy of the Col-CS-AuNP formulation in the MDI was assessed. The chitosan-capped gold nanoparticles (CS-AuNPs) and Col-CS-AuNPs had particle sizes of 44.34 ± 1.02 and 174.50 ± 4.46 nm, respectively. CS-AuNPs effectively entrapped 76.4% of colistin. Col-CS-AuNPs exhibited an initial burst release of up to 60% colistin within the first 6 h. The release mechanism was accurately described by the Korsmeyer-Peppas model, with an R2 > 0.95. The aerosol properties of the Col-CS-AuNP formulation in the MDI revealed a high fine particle fraction of 61.08%, mass median aerodynamic diameter of 2.34 µm, and geometric standard deviation of 0.21, with a delivered dose uniformity within 75-125% of the labeled claim. The Col-CS-AuNP MDI formulation completely killed Escherichia coli at 5× and 10× minimum inhibitory concentrations after 6 and 12 h of incubation, respectively. The toxicity of CS-AuNP and Col-CS-AuNP MDI formulations in upper and lower respiratory tract cell lines was lower than that of free colistin. The stability of the Col-CS-AuNP MDI formulation was maintained for at least 3 months. The Col-CS-AuNP MDI formulation effectively eradicated bacteria over a 12-h period, showing promise for advancing lung infection treatments.

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