35,853 results match your criteria gold nanoparticles

Construction of a pH/TGase "Dual Key"-Responsive Gold Nano-radiosensitizer with Liver Tumor-Targeting Ability.

ACS Biomater Sci Eng 2021 Jun 15. Epub 2021 Jun 15.

Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.

The method of tumor microenvironment (TME)-responsive aggregation has become a promising approach to enhance treatment effect by improving the accumulation of nanoparticles in tumors. The enzymatic cross-linking strategy has widely attracted attention owing to its good aggregation stability and biocompatibility. However, the enzymes in nontumor tissue can also catalyze the cross-linking reaction and reduce accumulation of nanoparticles in tumor. Read More

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Rapid Surface-Enhanced Raman Spectroscopy Detection of Chlorothalonil in Standard Solution and Orange Peels with Pretreatment of Ultraviolet Irradiation.

Bull Environ Contam Toxicol 2021 Jun 15. Epub 2021 Jun 15.

State Key Laboratory of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, 214122, Jiangsu, China.

At present, the detection of chlorothalonil is generally based on chromatography and immunoassay; both of which are time-consuming and costly. In this study, Surface-enhanced Raman Spectroscopy (SERS) has been successfully utilized in the detection of chlorothalonil coupled with photochemistry and meanwhile, gold nanoparticles were prepared to enhance the Raman signal. Two Raman peaks (2246 cm and 2140 cm) of chlorothalonil were appeared after ultraviolet (UV) irradiation compared to the original solution. Read More

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Non-invasive SERS serum detection technology combined with multivariate statistical algorithm for simultaneous screening of cervical cancer and breast cancer.

Anal Bioanal Chem 2021 Jun 14. Epub 2021 Jun 14.

First Affiliated Hospital of Xinjiang Medical University, Xinjiang, 830046, Urumqi, China.

Surface-enhanced Raman scattering (SERS), as a rapid, reliable and non-destructive spectral detection technology, has made a series of breakthrough achievements in screening and pre-diagnosis of various cancerous tumors. In this paper, high-performance gold nanoparticles/785 porous silicon photonic crystals (Au NPs/785 PSi PhCs) active SERS substrates were specially designed for serum testing, and realized highly sensitive detection of serum from healthy people, patients with cervical cancer and breast cancer. Based on the SERS spectra of the three groups of serum, the significant differences between the healthy group and cancer group at 1030 cm and 1051 cm were analyzed, and the similar but different serum SERS spectra of cervical cancer and breast cancer patients were compared. Read More

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The membrane-targeting mechanism of host defense peptides inspiring the design of polypeptide-conjugated gold nanoparticles exhibiting effective antibacterial activity against methicillin-resistant .

J Mater Chem B 2021 Jun 15. Epub 2021 Jun 15.

State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. and Key Laboratory for Ultrafine Materials of Ministry of Education, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China.

Multidrug-resistant bacterial infections are a grand challenge to global medical and health systems. Therefore, it is urgent to develop versatile antibacterial strategies that can combat bacterial resistance without displaying toxicity. Here, we synthesize antibacterial polypeptide-conjugated gold nanoparticles that exhibit potent antibacterial activities against clinically isolated multiple drug resistance Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus, and excellent in vitro and in vivo biocompatibility. Read More

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Wall teichoic acids govern cationic gold nanoparticle interaction with Gram-positive bacterial cell walls.

Chem Sci 2020 Mar 23;11(16):4106-4118. Epub 2020 Mar 23.

Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA

Molecular-level understanding of nanomaterial interactions with bacterial cell surfaces can facilitate design of antimicrobial and antifouling surfaces and inform assessment of potential consequences of nanomaterial release into the environment. Here, we investigate the interaction of cationic nanoparticles with the main surface components of Gram-positive bacteria: peptidoglycan and teichoic acids. We employed intact cells and isolated cell walls from wild type and two mutant strains differing in wall teichoic acid composition to investigate interaction with gold nanoparticles functionalized with cationic, branched polyethylenimine. Read More

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Sodium caseinate as a particulate emulsifier for making indefinitely recycled pH-responsive emulsions.

Chem Sci 2020 Mar 16;11(15):3797-3803. Epub 2020 Mar 16.

Research and Development Centre of Food Proteins, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products Safety, South China University of Technology Guangzhou 510640 P. R. China

pH-responsive emulsions are one of the simplest and most readily implementable stimuli-responsive systems. However, their practical uses have been greatly hindered by cyclability. Here, we report a robust pH-responsive emulsion prepared by utilizing pure sodium caseinate (NaCas) as the sole emulsifier. Read More

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Green Synthesis of Ciprofloxacin-Loaded Cerium Oxide/Chitosan Nanocarrier and Its Activity Against MRSA-Induced Mastitis.

J Pharm Sci 2021 Jun 11. Epub 2021 Jun 11.

Departments of Nanomedicine, California Innovations Corporation, San Diego, CA, USA. Electronic address:

Methicillin-resistant Staphylococcus aureus (MRSA)-induced mastitis is one of the biggest animal welfare issues and economic burdens worldwide. As a possible effective treatment, ciprofloxacin (CIP)-loaded cerium oxide (CeO)/chitosan (CS) nanocomposite was synthesized using an eco-friendly approach, characterized, and evaluated. From 350 mastitis-positive milk samples, 35 mecA-positive MRSA strains were confirmed by antibiotic sensitivity testing and PCR. Read More

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A One-Two-Three Multifunctional System for Enhanced Imaging and Detection of Intracellular MicroRNA and Chemogene Therapy.

ACS Appl Mater Interfaces 2021 Jun 14. Epub 2021 Jun 14.

Weifang Customs, Yuqing East Street, No.15789, High tech District, Weifang 261000, Shandong Province, China.

Simultaneous imaging, diagnosis, and therapy can offer an effective strategy for cancer treatment. However, the complex probe design, poor drug release efficiency, and multidrug resistance remain tremendous challenges to cancer treatment. Here, a novel one-two-three system is built for enhanced imaging and detection of miRNA-21 (miR-21) overexpressed in cancer cell and chemogene therapy. Read More

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Ion shuttling between emulsion droplets by crown ether modified gold nanoparticles.

Nanoscale Adv 2021 Apr 9;3(11):3136-3144. Epub 2021 Apr 9.

University of Liverpool, Department of Chemistry Crown Street Liverpool L69 7ZD UK

Selective unidirectional transport of barium ions between droplets in a water-in-chloroform emulsion is demonstrated. Gold nanoparticles (GNPs) modified with a thiolated crown ether act as barium ion complexing shuttles that carry the ions from one population of droplets () to another (). This process is driven by a steep barium ion concentration gradient between and droplets. Read More

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Green Approach: ''A Forwarding Step for Curing Leishmaniasis-A Neglected Tropical Disease''.

Front Mol Biosci 2021 28;8:655584. Epub 2021 May 28.

Department of Biosciences, Manipal University Jaipur, Jaipur, India.

The present review focuses on a dreaded vector-mediated leishmaniasis, with the existing therapeutic approaches including a variety of drugs along with their limitations, the treatment with natural compounds, and different types of metal/metal oxide nanoparticles (NPs). As evidenced, various metallic NPs, comprising silver, silver oxide, gold, zinc oxide, titanium, lead oxide, , played a curative role to treat leishmaniasis, are also presented. Keeping in view the advance success of vaccines against the prevalent dreaded diseases in the past and the present scenario, efforts are also being made to develop vaccines based on these NP formulations. Read More

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Nanogold Functionalized With Lipoamide-DGR: A Simple, Robust and Versatile Nanosystem for αvβ3-Integrin Targeting.

Front Chem 2021 28;9:690357. Epub 2021 May 28.

Tumor Biology and Vascular Targeting Unit, Division of Experimental Oncology, IRCCS San Raffaele Scientific Institute, Milan, Italy.

Gold nanoparticles functionalized with DGR, a tripeptide motif that recognizes αvβ3 integrin overexpressed in tumor vessels, have been used as nano-vectors for the delivery of cytokines to tumors. Functionalization of nanogold with this peptide has been achieved by coating nanoparticles with a peptide-albumin conjugate consisting of heterogeneous molecules with a variable number of linkers and peptides. To reduce nanodrug heterogeneity we have designed, produced and preclinically evaluated a homogeneous and well-defined reagent for nanogold functionalization, consisting of a head-to-tail cyclized CGDGRG peptide () coupled its thiol group to maleimide-PEG-lipoamide (LPA). Read More

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reversible tuning of chemical interface damping in single gold nanorod-based recyclable platforms through manipulation of supramolecular host-guest interactions.

Chem Sci 2021 Apr 15;12(20):7115-7124. Epub 2021 Apr 15.

Department of Chemistry, University of Ulsan 93 Daehak-ro, Nam-gu Ulsan 44610 Republic of Korea +82 52 712 8002 +82 52 712 8012.

Recently, chemical interface damping (CID) has been proposed as a new plasmon damping pathway based on interfacial hot-electron transfer from metal to adsorbate molecules. It has been considered essential, owing to its potential implications in efficient photochemical processes and sensing experiments. However, thus far, studies focusing on controlling CID in single gold nanoparticles have been very limited, and reversible tuning has remained a considerable challenge. Read More

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An interparticle relatively motional DNA walker and its sensing application.

Chem Sci 2020 Jun 30;11(28):7415-7423. Epub 2020 Jun 30.

School of Chemistry and Chemical Engineering, Shandong University 250100 Jinan P. R. China

DNA molecular machines are DNA self-assemblies that perform quasi-mechanical movement at the micro-nano scale, and have attracted increasing attention in the fields of biosensing, drug delivery and biocomputing. Herein, we report the concept and operation of an interparticle relatively motional DNA walker. The walker is composed of walking particles (WPs) and track particles (TPs). Read More

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Protease-responsive mass barcoded nanotranslators for simultaneously quantifying the intracellular activity of cascaded caspases in apoptosis pathways.

Chem Sci 2020 May 4;11(20):5280-5288. Epub 2020 May 4.

State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China

Quantitatively delineating the activation network of multiple proteases that participate in cellular processes is highly essential for understanding the physiological and pathological states of cells. In this study, protease-responsive mass barcoded nanotranslators (PRMNTs) were engineered for revealing the activity of cascaded caspases in apoptosis in a multiplex and quantitative manner. In the PRMNTs, a series of mass tag-decorated gold nanoparticles (AuNPs) were tethered onto magnetic FeO nanospheres a linker containing the substrate peptide of the target protease to form a "one-to-many" core-satellite structure. Read More

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Nanomaterials and their composite scaffolds for photothermal therapy and tissue engineering applications.

Sci Technol Adv Mater 2021 Jun 4;22(1):404-428. Epub 2021 Jun 4.

Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan.

Photothermal therapy (PTT) has attracted broad attention as a promising method for cancer therapy with less severe side effects than conventional radiation therapy, chemotherapy and surgical resection. PTT relies on the photoconversion capacity of photothermal agents (PTAs), and a wide variety of nanomaterials have been employed as PTAs for cancer therapy due to their excellent photothermal properties. The PTAs are systematically or locally administered and become enriched in cancer cells to increase ablation efficiency. Read More

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Gold and silver nanoparticles: Green synthesis, microbes, mechanism, factors, plant disease management and environmental risks.

Saudi J Biol Sci 2021 Jun 9;28(6):3624-3631. Epub 2021 Apr 9.

Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.

Metal nanoparticles were being used in different processes of developmental sectors like agriculture, industry, medical and pharmaceuticals. Nano-biotechnology along with sustainable organic chemistry has immense potential to reproduce innovative and key components of the systems to support surrounding environment, human health, and industry sustainably. Different unconventional methods were being used in green chemistry to synthesize gold and silver nanoparticles from various microbes. Read More

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A deep learning approach to gold nanoparticle quantification in computed tomography.

Phys Med 2021 Jun 11;87:83-89. Epub 2021 Jun 11.

Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA 01854, United States.

Introduction: Deep learning (DL) is used to classify, detect, and quantify gold nanoparticles (AuNPs) in a human-sized phantom with a clinical MDCT scanner.

Methods: AuNPs were imaged at concentrations between 0.0274 and 200 mgAu/mL in a 33 cm phantom. Read More

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Colorimetry and SERS dual-mode sensing of serotonin based on functionalized gold nanoparticles.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Jun 5;261:120057. Epub 2021 Jun 5.

College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun 130012, China. Electronic address:

In this study, we reported a colorimetry and SERS dual-mode sensing of serotonin (5-HT) based on functionalized gold nanoparticles (AuNPs). Based on the amino and hydroxyl groups in 5-HT can react with dithiobis succinimidyl propionate (DSP) and N-acetyl-L-cysteine (NALC) respectively, we synthesized two kinds of functionalized AuNPs (DSP-AuNPs and NALC-AuNPs). A double interaction between functionalized nanoparticles and the hydroxyl and the amino group of serotonin led to interparticle-crosslinking aggregation. Read More

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In situ reduction triggers the highly sensitive detection of pesticide by classic gold nanoparticle and quantum dots nanocomposite.

Anal Chim Acta 2021 Aug 24;1172:338679. Epub 2021 May 24.

College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China; Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, China. Electronic address:

Fluorescence "turn on" method is always preferable for target detection under the urgent demand to develop point-of-care portable sensors in practical applications due to its higher selectivity and less false positives. However, there is only few reports of pesticide monitoring based on this strategy so far most probably ascribed to its poor hydrophilicity and reactivity. In this work, triggered by reductant tris (2-carboxyethyl) phosphine hydrochloride (TCEP), initially fluorescence-quenched gold nanoparticles (Au NPs)-decorated quantum dots (QDs)-embedded nanobead shows obvious fluorescence "turn on" signal response to thiram with concentration response range of 0. Read More

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Biosynthesis of gold nanoparticles for the treatment of osteoarthritis alone or in combination with Diacerein in a rat model.

Inflammopharmacology 2021 Jun 11. Epub 2021 Jun 11.

Department of Food Toxicology and Contaminants, National Research Center, Dokki, Cairo, Egypt.

Gold (Au) compounds were used as an effective therapeutic agent for various inflammatory diseases; however, the use of Au compounds becomes limited because of its association with several side effects. Hence, gold nanoparticles (AuNPs) were developed as a new option for the medical proposes. However, the safety evaluation of gold nanoparticles (AuNPs) in osteoarthritis (OA) treatment remains vague. Read More

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Fabrication and measurement of fiber optic localized surface plasmon resonance sensor based on gold nanoparticle dimer.

Spectrochim Acta A Mol Biomol Spectrosc 2021 May 29;261:120034. Epub 2021 May 29.

Department of Electronics and Electrical Engineering, Dankook University, Yongin 16890, South Korea. Electronic address:

Fiber optic localized surface plasmon resonance (FO LSPR) sensors capable of portable, real-time, and remote sensing are emerging with the progress of lab-on-fiber technology. However, the small area of the substrate by the optical fiber often restricts the sensitivity of the FO LSPR sensors. To improve the performance of the FO LSPR sensors, it is necessary to enhance the interactions between incident light and plasmonic nanostructures within a defined region. Read More

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Interference-free photoelectrochemical immunoassays using carboxymethylated dextran-coated and gold-modified TiO nanotube arrays.

Anal Bioanal Chem 2021 Jun 11. Epub 2021 Jun 11.

Institute of Surface Analysis and Chemical Biology, University of Jinan, Jinan, Shandong, 250022, People's Republic of China.

An interference-free photoelectrochemical (PEC) immunoassay was developed for cardiac troponin I (cTnI) detection. Covalent linkage of cTnI antibody to carboxymethylated (CM-) dextran pre-immobilized onto a gold nanoparticles (AuNPs)-modified TiO nanotube array (NTA) affords five consecutive analyte captures with surface regenerations in between. Changes in the photocurrents at this photoanode before and after cTnI captures can be well fitted with the Langmuir isotherm from 0. Read More

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Anticancer activity of indapamide adsorbed on gold nanoparticles: DFT, in-silico, and in-vitro analysis.

J Mol Recognit 2021 Jun 11:e2920. Epub 2021 Jun 11.

Centre for Advanced Functional Materials, Department of Physics, Bishop Moore College, Mavelikara, Kerala, 690110, India.

The adsorption properties of the lung cancer agent indapamide (IND) on gold nanoparticles (AuNPs), were studied with the help of surface-enhanced Raman scattering techniques. The structure-activity of the IND and INDA molecule has been studied using DFT/B3LYP methodology. NBO analysis reveals that, both the molecules are stabilized by a C─H O intramolecular hydrogen bonding, apart from the conjugative and intramolecular charge transfer interactions. Read More

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Taqman-MGB nanoPCR for Highly Specific Detection of Single-Base Mutations.

Int J Nanomedicine 2021 28;16:3695-3705. Epub 2021 May 28.

Department of Transfusion Medicine, Southwest Hospital, Third Military Medical University, Army Medical University, Chongqing, 400038, People's Republic of China.

Purpose: Detection of single-base mutations is important for real-time monitoring of tumor progression, therapeutic effects, and drug resistance. However, the specific detection of single-base mutations from excessive wild-type background sequences with routine PCR technology remains challenging. Our objective is to develop a simple and highly specific qPCR-based single-base mutation detection method. Read More

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Large scale self-assembly of plasmonic nanoparticles on deformed graphene templates.

Sci Rep 2021 Jun 10;11(1):12232. Epub 2021 Jun 10.

Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.

Hierarchical heterostructures of two-dimensional (2D) nanomaterials are versatile platforms for nanoscale optoelectronics. Further coupling of these 2D materials with plasmonic nanostructures, especially in non-close-packed morphologies, imparts new metastructural properties such as increased photosensitivity as well as spectral selectivity and range. However, the integration of plasmonic nanoparticles with 2D materials has largely been limited to lithographic patterning and/or undefined deposition of metallic structures. Read More

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Measurement of Navier Slip on Individual Nanoparticles in Liquid.

Nano Lett 2021 Jun 10. Epub 2021 Jun 10.

ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia.

The Navier slip condition describes the motion of a liquid relative to a neighboring solid surface, with its characteristic Navier slip length being a constitutive property of the solid-liquid interface. Measurement of this slip length is complicated by its small magnitude, expected to be in the nanometer range based on molecular simulations. Here, we report an experimental technique that interrogates the Navier slip length on individual nanoparticles immersed in liquid with subnanometer precision. Read More

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Surface Plasmon Resonance Assay for Identification of Small Molecules Capable of Inhibiting Aβ Aggregation.

ACS Appl Mater Interfaces 2021 Jun 10. Epub 2021 Jun 10.

Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore 117599, Singapore.

Toxic aggregates of amyloid-beta (Aβ) have importance in the pathology of Alzheimer's disease, and inhibition of aggregate formation is considered to be a promising strategy for drug development. Here, we report a simple and rapid surface plasmon resonance (SPR) assay method that can identify potential Aβ aggregation inhibitors. Our assay is based on the SPR shifting of the Aβ-gold nanoparticle (Aβ-GNP) aggregates by size under the influence of an Aβ aggregation inhibitor. Read More

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Biodegradable Polymers and Gold Nanoparticle-Decorated Skin Substitutes: Synthesis, Characterization, and In Vitro Biological Activities.

Appl Biochem Biotechnol 2021 Jun 10. Epub 2021 Jun 10.

Department of Chemistry, Avinashilingam Institute for Home Science and Higher Education for Women, 641043, Coimbatore, India.

Skin substitutes are a restorative material used to treat many skin injuries by replacing or masking the wound. It is also capable of producing an original skin type. In this study, gold nanoparticle-aided skin substitutes were prepared using biodegradable materials (chitosan, sodium alginate, and gelatin) under the magnetic stirring method. Read More

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Optimization of plasmonic metal structures for improving the hydrogen production efficiency of metal-organic frameworks.

Nanoscale 2021 Jun 10. Epub 2021 Jun 10.

Department of Chemistry, School of Science, Beijing Jiaotong University, Beijing 100044, People's Republic of China.

The introduction of plasmonic metals of gold (Au) nanoparticles onto metal-organic frameworks (MOFs) has been testified as an efficient approach to boost the H2 evolution ability because the excited Au particles can generate hot electrons that can then be injected into MOFs to inhibit the recombination of charges. Generally, Au particles possess two modes of polarization, which are transverse and longitudinal polarizations. However, which of the two modes is more efficient remains unclear and is yet to be disclosed. Read More

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Bimetallic Au-Ag on a Patterned Substrate Derived from Discarded Blu-ray Discs: Simple, Inexpensive, Stable, and Reproducible Surface-Enhanced Raman Scattering Substrates.

Langmuir 2021 Jun 10. Epub 2021 Jun 10.

National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani 12120, Thailand.

A simple and reproducible surface enhanced Raman scattering (SERS) substrate of bimetallic gold-silver (Au-Ag) based on discarded a Blu-ray disc read only memory (BD-ROM) was developed by simply incorporating electrochemical (EC) treatment and chemical reaction. The resurfaced AgBD-ROM substrate (r-AgBD-ROM) was fabricated by EC treatment on a Ag film layer in BD-ROM (AgBD-ROM) to generate silver nanoparticles (AgNPs) on the indented pattern surface. Then, galvanic displacement reaction of Au and Ag was carried out to prepare the bimetallic Au-Ag structure (Au-r-AgBD-ROM). Read More

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