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oe1(光电查) - 科学论文

12 条数据
?? 中文(中国)
  • Colorimetric detection of normetanephrine, a pheochromocytoma biomarker, using bifunctionalised gold nanoparticles

    摘要: A simple and effective colorimetric method for the detection of normetanephrine (NMN), an O-methylated metabolite of norepinephrine, using functionalised gold nanoparticles is described. This metabolite is an important biomarker in the diagnosis of adrenal tumours such as pheocromocytoma or paraganglioma. The colorimetric probe consists of spherical gold nanoparticles (AuNPs) functionalised with two different ligands, which specifically recognize different functional groups in normetanephrine. Thus, a benzaldehyde-terminated ligand was used for the recognition of the amino alcohol moiety in NMN, by forming the corresponding oxazolidine. On the other hand, N-acetyl-cysteine was chosen for the recognition of the phenolic hydroxyl group through the formation of hydrogen bonds. The selective double molecular recognition between the probe and the hydroxyl and the amino-alcohol moieties of normetanephrine led to interparticle-crosslinking aggregation resulting in a change in the color of the solution, from red to blue, which could be observed by naked eye. The probe was highly selective towards normetanephrine and no color changes were observed in the presence of other neurotransmitter metabolites such as homovanillic acid (HVA) (dopamine metabolite), 5-hydroxyindoleacetic acid (5-HIAA) (serotonin metabolite), or other biomolecules present in urine such as glucose (Glc), uric acid (U.A), and urea. Finally, the probe was evaluated in synthetic urine with constituents that mimic human urine, where a limit of detection of 0.5 mM was achieved.

    关键词: Gold nanoparticles,Aggregation,Pheocromocytoma,Normetanephrine,Colorimetric detection

    更新于2025-09-23 15:23:52

  • Colorimetric detection of copper ions using gold nanorods in aquatic environment

    摘要: On the basis of that Cu2+ can accelerate the leaching rate of Au by thiosulfate, a colorimetric, unlabeled and non-aggregating gold nanorod (GNR) probe has been developed for the determination of trace-level Cu2+ in aqueous solutions. Our study demonstrates a high sensitivity and rapid response towards Cu2+ with a detectable range (20–200 nM). E?ect factors such as the ratio of NH3/NH4Cl, the concentration of S2O3 2?, the bath temperature and the heating time were researched to investigate the in?uences on the copper detection process by GNRs sensor. The method studied in this project is highlighted by its high selectivity and high tolerance to interferences, which can be used to detect trace amounts of Cu2+ ions in water samples quickly and sensitively, indicating the potential suitability of copper detection in various applications.

    关键词: Gold nanorods,Copper ions,Catalytic leaching,Colorimetric detection

    更新于2025-09-23 15:22:29

  • Development of Ion Exchange Ligands with High Separation Performance and Colorimetric Analysis Using Gold Nanoparticles Decorated with The Functional Ligands

    摘要: Development of metal separating reagents with high selectivity is necessary for efficient separation and recovery of valuable metals contained in industrial wastes, and removal and detection of toxic metals. We have developed novel metal separating ligands with a diglycolamic acid (DGAA) framework. The ligands have a tridentate coordination structure consisting of an amide group and a carboxy group connected by an ether chain and provide a metal separation ability superior to that of commercial ligands. Since the ligands can be synthesized simply in one step, this helps to reduce the production costs of the ligands. In the present review article, we report the extraction characteristics of DGAA-type ligand for 56 kinds of metal ions, extraction separation of rare-earth metal ions, and removal of toxic metal ions. Furthermore, a one-pot biological approach to fabricate DGAA-decorated gold nanoparticles has been developed using the DGAA-type ligand fused to the N-terminus of a gold-binding peptide. It was found that the DGAA-decorated gold nanoparticles can act as a high-sensitive colorimetric sensor for detecting toxic metal ions with color change.

    关键词: Ion-exchange materials,Gold nanoparticles,Diglycolamic acid,Colorimetric detection,Metal separating reagents,Separation and recovery

    更新于2025-09-23 15:22:29

  • Biosensing Technologies for the Detection of Pathogens - A Prospective Way for Rapid Analysis || Development of HRPzyme-Integrated PCR Platform for Colorimetric Detection of Foodborne Pathogens

    摘要: In recent years, foodborne illnesses have become the most significant public health issue in both developed and developing countries. The World Health Organization (WHO) reported that in 2010, around 1.8 million people died due to foodborne illness. Therefore, the development of a cost-effective, sensitive, and selective detection method for identifying and monitoring foodborne pathogens is necessary for improved public health. Here, we describe a simple and ultrasensitive colorimetric method for the detection of foodborne pathogens based on HRPzyme-integrated PCR using PC-based ImageJ software. We present insights into different aspects of this method such as the importance of 16S rRNA detection, the modification of traditional PCR primers with a unique functional sequence for generating a color signal, and the application of ImageJ in colorimetric image data acquisition. The performance of the proposed strategy in detecting various foodborne pathogens is comparable to that of the commercial UV-Vis spectrophotometer Tecan Infinite 200 Pro. This detection platform exhibits linearity over wide range, high sensitivity, and high selectivity. The diagnostic capability of this colorimetric system to detect foodborne pathogens was demonstrated with spiked fruit and vegetable samples. This low-cost and effective colorimetric method can be conveniently employed for the analysis of DNA sequences arising from pathogenic bacteria.

    关键词: PCR,HRPzyme,primer,16S rRNA,colorimetric detection,foodborne pathogens

    更新于2025-09-23 15:21:21

  • Design, synthesis, crystal structure and cytotoxicity studies of colorimetric fluorescent “OFF-ON” probes for rapid detection of hydrogen sulfide based on Cu(II) complex

    摘要: Four colorimetric fluorescent probes based on copper(II) complexes were synthesized and the molecular structures were characterized by X-ray diffraction, ESI-HRMS and elemental analysis. When exposed to HS–, the synthesized probes showed significant color changes from yellow to red and remarkable increase of fluorescence intensity (over 80-fold). What’s more, the interaction of host-guest could be completed in 2 minutes. However, no clear color and fluorescence intensity changes were observed in the presence of other anions (AcO–, H2PO4–, F–, Cl–, Br–, I–, SO42-, SO32-, CO32-, Cys and GSH). The synthesized colorimetric fluorescent probes could detect HS– rapidly and conveniently. Cytotoxicity studies indicated that the synthesized fluorescent probes were low cytotoxicity in Hela cells and may be used to detect H2S level in vivo.

    关键词: hydrogen sulfide,copper complex crystal,fluorescent probe,colorimetric detection,cytotoxicity

    更新于2025-09-23 15:21:01

  • Metallic nanoparticles enabled sensing of drug-of-abuse, an attempt to forensic application

    摘要: Gamma-hydroxybutyric acid (GHB) functions as depressant on the central nerve systems and serves as pharmaceutical agent in the treatment of narcolepsy and alcohol withdraw. In recent year, GHB has been misused as recreational drug due to its ability to induce euphoric feelings. Moreover, it has gained increasing attentions as a popular drug of abuse which is frequently related to drug-facilitated sexual assaults. By now, chromatography exhibit detection methods based on extraordinary sensitivity for GHB sensing. However, such techniques require complicated sample treatment prior to analysis. Optical sensors provide an alternative approach for rapid and simple analysis of GHB samples. Unfortunately, currently reported probes are mostly based on hydrogen bonding to recognize GHB, which may raise concern such as lack of specificity. In this work, we reported a bioinspired strategy for selective sensing of GHB. Such method is based on specific enzyme recognition to allow highly selective detection of GHB with minimum interference even in complex sample matrix (e.g. simulated urine). In addition, the result can be obtained by either quantitative spectroscopy analysis as well as colormetric change observed by naked-eye demonstrating the potential application in drug screening and forensic analysis.

    关键词: drug sensing,Au NPs,colorimetric detection

    更新于2025-09-23 15:19:57

  • Dual-Color Plasmonic Nanosensor for Radiation Dosimetry

    摘要: Radiation dosimeters are critical for accurately assessing the levels of radiation exposure of tumor sites and surrounding tissues and for optimizing therapeutic interventions as well as for monitoring environmental exposure. To fill the need for a simple, user-friendly and inexpensive dosimeter, we designed an innovative colorimetric nanosensor-based assay for detecting ionizing radiation. We show that hydroxyl radicals generated by ionizing radiation can be used to etch gold nanorods (AuNRs) and silver nanoprisms (AgNPRs), yielding reproducible color changes for radiation dose detection in the range of 50-2000 Rad, broad enough to cover doses used in hyperfractionated, conventional, and hypofractionated radiotherapy. This range of doses detected by this assay correlates with radiation induced DNA damage response in mammalian cells. Furthermore, this AuNR- and AgNPR-based sensing platform has been established in a paper format that can be readily adopted for a wide range of applications and translation.

    关键词: Radiation dosimetry,gold nanorods,silver nanoprisms,dual-color nanosensor,colorimetric detection

    更新于2025-09-23 15:19:57

  • Smartphone coupled with a paper-based optode: Towards a selective cyanide detection

    摘要: A low-cost on-paper sensor based on 5,10,15-tritolylcorrolatocobalt(III) triphenylphosphine, CoTTCorr(PPh3), was developed for cyanide detection in aqueous solutions. The sensor was coupled to a smartphone and used a home-written color intensity analysis software in order to record and interpret the colorimetric response. The detection of cyanide was possible down to 0.053 mg/L, an order of magnitude lower than the value of 0.5 mg/L set by the World Health Organization (WHO) for safe short-term exposure of cyanide in potable water. The colorimetric sensor had selectivity toward cyanide ions over the anions Cl-, Br, F-, NO2, SCN-, OAc-,ClO4- while the influence of NO3 ions on the sensor optical response towards cyanide was overcome by optimization of the ionophore/anion-exchanger ratio inside the sensing material. The best performance was obtained for the optode with an ionophore to exchanger ratio of 1:3. The optimized optodes were employed for quantification of cyanide content added to potable water and saliva.

    关键词: 5,cyanide sensor,15-tritolyl corrolate Co(III) triphenylphosphine,colorimetric detection,10

    更新于2025-09-19 17:13:59

  • Highly Sensitive Detection of Salbutamol by ALP-mediated Plasmonic ELISA Based on Controlled Growth of AgNPs

    摘要: Salbutamol (SAL), a short-acting β-2 adrenergic receptor agonist, is an undesirable addition to livestock farming and used to improve the growth rates. A direct competitive colorimetric immunoassay for SAL was developed. The alkaline phosphatase (ALP)-mediated controlled growth of the prereduction silver nanoparticles (AgNPs) was used to achieve the highly sensitive, colorimetric detection of SAL through the plasmonic ELISA. Click chemistry reaction was used to synthesize salbutamol biotin label (SAL-Bio) to achieve signal amplification and specific binding with antibody. ALP can efficiently hydrolyze sodium L-ascorbyl-2-phosphate and generate L-ascorbic acid, thereby reducing Ag+ and forming AgNPs. The plasmon resonance absorption signals of AgNPs were enhanced along with a distinct color change. The limit of detection of SAL can be decreased to 26.14 pg/mL. The method offers a good technique for the detection of many small molecular contaminants, such as pesticide residues and veterinary drug residues in food and edible water.

    关键词: Salbutamol,alkaline phosphatase,colorimetric detection,direct competitive immunoassay,plasmonic ELISA,silver nanoparticles

    更新于2025-09-19 17:13:59

  • [IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Mobile Based in Situ Detection of Live/Dead and Antibiotic Resistant Bacteria by Silver Nanorods Array Sensor Fabricated by Glancing Angle Deposition

    摘要: The rapid in-situ detection of viability of bacteria is essential for human health and environmental care. It has become one of the biggest needs in biological and medical sciences to prevent infections and diseases, which usually occur in hospitals and field clinics. Nowadays, antibiotic resistance (ABR) has been grown as one of the world’s acutest public health problems, which requires a quick and efficient solution. Here, we demonstrate an easy, sensitive, user-friendly, portable, cost effective and time saving approach for detection of live, dead and drug resistant bacteria. Most of the organisms are found to produce H2S gas by their metabolism system. The endogenous H2S evolution was targeted to differentiate between live and dead as well as ABR bacteria. The silver nanorods (AgNRs) arrays sensors were fabricated by glancing angle deposition technique. The colorimetric and water wettability (contact angle) features of as-synthesized AgNRs were found to be highly sensitive and selective for hydrogen sulfide (H2S) gas. E.coli, P. aeruginosa, B. subtilis and S. aureus were used as the model organisms for this study. A drastic visible change in color as well as wetting properties of AgNRs array was observed. To make it easy, a user friendly and field deployable android based mobile app ‘Colorimetric Detector’ was developed. This dual mode detection is facile, inexpensive and can be easily scaled-up in the field of disease diagnosis.

    关键词: mobile app,colorimetric detection,silver nanorods,antibiotic resistance,bacteria detection,H2S gas

    更新于2025-09-11 14:15:04