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- 摘要
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- 实验方案
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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
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A colorimetric and fluorometric oligothiophene-indenedione-based sensor for rapid and highly sensitive detection of cyanide in real samples and bioimaging in living cells
摘要： A new simple oligothiophene-indenedione-based sensor 3TI has been synthesized for the highly reactive and selective detection of cyanide anion (CN?) in 70% aqueous media. The sensor 3TI displays distinct colorimetric and fluorometric detection of CN? due to the addition of CN? to the electron-deficient indenedione-vinyl group of 3TI, which hampers intramolecular charge transfer (ICT) efficiencies. The recognition mechanism of 3TI for CN? was confirmed by the optical measurements, 1H NMR titration, FTIR spectra, HRMS analysis, and TD-DFT calculations. The sensor 3TI for CN? shows the outstanding advantages of high fluorescence brightness, fast response time (30 s), low detection limit (31.3 nM), minimal pH dependence in the physiologically relevant range, and excellent selectivity in presence of other competitive anions. Encouraged by these desirable sensing properties, the 3TI has been successfully used for determination of CN? in real water and food samples, silica-based sensing kits and fluorescence imaging in living cells with satisfactory results.
关键词： Fluorometric sensor,Cyanide,Oligothiophene-indenedione,Colorimetric sensor,Real sample,Live-cell imaging
更新于2025-09-23 15:23:52
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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
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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
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A novel colorimetric and ratiometric fluorescent probe for cysteine based on conjugate addition-cyclization-elimination strategy with a large Stokes shift and bioimaging in living cells
摘要： Based on conjugate addition-cyclization reaction of Cys with acrylate and subsequent 1,6-elimination of p-hydroxybenzyl moiety, a novel colorimetric and ratiometric fluorescent probe 1 was designed and synthesized. Upon addition of Cys to the solution of 1, the absorption spectra changed from 508 nm to 452 nm (?56 nm) and afforded visible color change from pink to yellow. Meanwhile, the emission spectra shifted from 644 nm to 539 nm (?105 nm) with remarkable changes in the emission ratio of F539 nm/F644 nm (R/R0 up to 760-fold), accompanying with an obvious fluorescence change from orange to green under illumination with a 365 nm UV lamp. In addition, 1 exhibited a large Stokes shift (136 nm), high sensitivity (detection limit of 46.7 nM), and excellent selectivity to Cys over Hcy and GSH. Moreover, 1 can discriminate Cys from Hcy and GSH by fluorescence spectra, even obvious visible and fluorescence color changes. Importantly, 1 can be used to image Cys in living cells by dual emission channels.
关键词： Fluorescent probe,Cysteine,Ratiometric,Bioimaging,Colorimetric
更新于2025-09-23 15:22:29
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Optical aptasensor based on silver nanoparticles for the colorimetric detection of adenosine
摘要： A new and straightforward optical sensor for the colorimetric determination of adenosine (AD) in human urine samples was developed. The sensor comprised silver nanoparticles (AgNPs) as colorimetric elements and anti-AD aptamer (AP) as a recognition probe. In a solution containing AD and high concentration of NaCl, due to the unique binding of AD with AP, the aggregated metal nanomaterials dispersed in the solution, and the color intensity of the solution was changed accordingly. The absorbance of the solution was monitored for AD quantification. The method was applicable for the determination of AD in the concentration range of 60–280 nM with the detection limit of 21 nM. The relative standard deviation ranged from 4.8 to 8.8% for six replicates. The method showed excellent selectivity toward AD checked over some probable interfering compounds. To investigate the performance of AgNPs, the analytical characteristics of the method including linear range, detection limit, selectivity, and precision were compared with those obtained by a common AuNPs-based aptasensor. The reliability of the method was further ascertained for the detection of AD in urine samples of two lung cancer patients with percentage recoveries in the range of 98–107%.
关键词： Adenosine,Silver nanomaterials,Colorimetric,UV–vis absorption spectroscopy,Aptamer
更新于2025-09-23 15:22:29
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A novel ratiometric and colorimetric fluorescent probe for hydrazine based on ring-opening reaction and its applications
摘要： In recent years, with the increasing awareness of environmental protection, the detection of industrial emissions has become more and more strict. Hydrazine, as a common reactive group, the excessive emissions by the widespread use is inevitably harmful to the environment and human beings. To respond positively to environment protection policies at home and abroad, the development of a convenient and effective hydrazine probe has become an important subject for many research groups. In this work, a derivative containing lactone ring was synthesized based on naphthalimide. This probe displayed a fast colorimetric and ratiometric fluorescent response for hydrazine with high selectivity and sensitivity based on the ring-opening reaction. The detection limit of the probe for hydrazine is about 0.2032 μM (< 10 ppb). It is worth mentioning that the probe can successfully apply to detect gaseous hydrazine when the probe is loaded on the periopaper. Furthermore, the results of biological imaging experiment indicated that the probe can detect the hydrazine at the cellular level.
关键词： Cell imaging,Lactone ring,Hydrazine,Ring-opening,Ratiometric and colorimetric
更新于2025-09-23 15:22:29
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High-performance and Multifunctional Colorimetric Humidity Sensors Based on Mesoporous Photonic Crystals and Nanogels
摘要： Colorimetric sensors, as a key branch of the application of photonic crystals (PCs), sets off enthusiasm of scientists to make research. Here, simple mesoporous and structurally colored one-dimensional photonic crystals (1DPCs) constructed by alternating assembly of poly(acrylamide-N,N'-methylene bisacrylamide) (P(AM-MBA)) nanogels and TiO2 nanoparticles are reported as high-performance colorimetric humidity sensors. The sensors with bright colors display rapid response to relative humidity (RH) change and reach sensing balance in 0.5 s. By varying RH from 47.0% to 89.3%, stopband of a sensor changes from 426 nm to 668 nm, almost spanning the whole visible range. Meanwhile, visual sensing of RH possesses good reversibility and repeatability. Moreover, the sensors with delicate patterns are facilely fabricated by partial UV photodegradation of the polymer layers with nano TiO2 as catalyst. The delicate patterns and backgrounds show different colors, and change color simultaneously and quickly by varying the ambient humidity. Accurate QR code pattern is also realized on the PC sensor, it is found successful reading of the data is only achieved by increasing RH to realize high color contrast between the code and background. Given their excellent properties, the porous hybrid PCs are promising as high-performance humidity sensors with potential display, decoration, information-storage and encryption functions.
关键词： colorimetric humidity sensors,photonic crystals,nanogels,patterning,mesoporous structure
更新于2025-09-23 15:21:21
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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
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A nanomolar detection of mercury(II) ion by a chemodosimetric rhodamine-based sensor in an aqueous medium: Potential applications in real water samples and as paper strips
摘要： A new promising rhodamine based colorimetric and fluorometric chemosensor, RDV has been designed and synthesized for specific detection of Hg2+ ion. It acts as highly selective “turn-on” fluorescent chemosensor for Hg2+ ion without interference from other competitive metal ions in aqueous acetonitrile medium. The drastic color change with addition of Hg2+, from colorless to pink, indicates RDV can acts as “naked-eye” indicator for Hg2+. The Hg2+ promoted selective hydrolysis of appended vinyl ether group in RDV followed by Hg2+ chelated complex formation with concomitant opening of spirolactam ring is the plausible sensing mechanism. The detailed absorption, fluorescence, 1H NMR, 13C NMR and mass spectrometry confirms the proposed sensing mechanism. The limit of detection (LOD) of Hg2+ by RDV is 136 nM indicating the high sensitivity towards Hg2+. The RDV shows consistent spectroscopic response in biological pH range 4-10. In addition to explore practical applicability of RDV, its paper strips have been made and used to detect Hg2+ in pure water solution up to 10 ppm level. Furthermore, the potential application of RDV for the sensing of Hg2+ in real water samples (tap water and drinking waters from different sources) were also monitored and demonstrated.
关键词： Paper strip application,Oxymercuration,Colorimetric,Chemodosimeter,Fluorescent
更新于2025-09-23 15:21:21