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1.
Food Res Int ; 183: 114175, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760120

RESUMO

Lactose hydrolysed concentrated milk was prepared using ß-galactosidase enzyme (4.76U/mL) with a reaction period of 12 h at 4 °C. Addition of polysaccharides (5 % maltodextrin/ß-cyclodextrin) to concentrated milk either before or after lactose hydrolysis did not result in significant differences (p > 0.05) in degree of hydrolysis (% DH) of lactose and residual lactose content (%). Three different inlet temperatures (165 °C, 175 °C and 185 °C) were used for the preparation of powders which were later characterised based on physico-chemical and maillard browning characteristics. Moisture content, solubility and available lysine content of the powders decreased significantly, whereas, browning parameters i.e., browning index, 5-hydroxymethylfurfural, furosine content increased significantly (p < 0.05) with an increase in inlet air temperature. The powder was finally prepared with 5 % polysaccharide and an inlet air temperature of 185 °C which reduced maillard browning. Protein-polysaccharide interactions were identified using Fourier Transform infrared spectroscopy, fluorescence spectroscopy and determination of free amino groups in the powder samples. Maltodextrin and ß-cyclodextrin containing powder samples exhibited lower free amino groups and higher degree of graft value as compared to control sample which indicated protein-polysaccharide interactions. Results obtained from Fourier Transform infrared spectroscopy also confirmed strong protein-polysaccharide interactions, moreover a significant decrease in fluorescence intensity was also observed in the powder samples. These interactions between the proteins and polysaccharides reduced the maillard browning in powders.


Assuntos
Furaldeído , Lactose , Reação de Maillard , Leite , Polissacarídeos , Pós , Lactose/química , Polissacarídeos/química , Leite/química , Animais , Espectroscopia de Infravermelho com Transformada de Fourier , Furaldeído/análogos & derivados , Furaldeído/química , beta-Galactosidase/metabolismo , beta-Ciclodextrinas/química , Hidrólise , Secagem por Atomização , Temperatura , Lisina/química , Lisina/análogos & derivados , Solubilidade , Espectrometria de Fluorescência , Proteínas do Leite/química , Manipulação de Alimentos/métodos
2.
ACS Appl Bio Mater ; 7(5): 3460-3468, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38703374

RESUMO

Trimethylamine N-oxide (TMAO), a molecule produced by the microbiota, has been associated with human health and illness. Its early discovery in body fluids may affect our understanding of the pathophysiology and treatment of many illnesses. Therefore, our knowledge of the pathophysiology and diagnostics of disorders associated with TMAO might be enhanced by the creation of dependable and fast methods for TMAO detection. Therefore, we developed a fluorescent probe for detecting TMAO utilizing an on-off-on strategy. Bovine serum albumin (BSA)@AuNCs luminescence is effectively quenched by Mo4+ because BSA@AuNCs and Mo4+ have a strong binding relationship. Mo4+ ions can substantially decrease the emission intensity of gold nanoclusters by establishing a BSA@AuNCs-Mo system. Then, the luminescence of BSA@AuNCs was restored due to the interaction between Mo4+ and TMAO. A significant linear relationship was seen between the emission intensity and TMAO concentration within the 0-201 µM range, with a detection limit of 1.532 µM. Additionally, the method can measure TMAO in blood and urine samples.


Assuntos
Corantes Fluorescentes , Ouro , Teste de Materiais , Nanopartículas Metálicas , Metilaminas , Tamanho da Partícula , Soroalbumina Bovina , Metilaminas/química , Ouro/química , Soroalbumina Bovina/química , Nanopartículas Metálicas/química , Humanos , Corantes Fluorescentes/química , Materiais Biocompatíveis/química , Bovinos , Animais , Fluorescência , Espectrometria de Fluorescência , Estrutura Molecular
3.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731451

RESUMO

A novel second-generation blue fluorescent polyamidoamine dendrimer peripherally modified with sixteen 4-N,N-dimethylaninoethyloxy-1,8-naphthalimide units was synthesized. Its basic photophysical characteristics were investigated in organic solvents of different polarity. It was found that in these solvents, the dendrimer is colorless and emitted blue fluorescence with different intensities depending on their polarity. The effect of the pH of the medium on the fluorescence intensity was investigated and it was found that in the acidic medium, the fluorescence is intense and is quenched in the alkaline medium. The ability of the dendrimer to detect metal ions (Pb2+, Zn2+, Mg2+, Sn2+, Ba2+, Ni2+, Sn2+, Mn2+, Co2+, Fe3+, and Al3+) was also investigated, and it was found that in the presence of Fe3+, the fluorescent intensity was amplified more than 66 times. The antimicrobial activity of the new compound has been tested in vitro against Gram-positive B. cereus and Gram-negative P. aeruginosa. The tests were performed in the dark and after irradiation with visible light. The antimicrobial activity of the compound enhanced after light irradiation and B. cereus was found slightly more sensitive than P. aeruginosa. The increase in antimicrobial activity after light irradiation is due to the generation of singlet oxygen particles, which attack bacterial cell membranes.


Assuntos
Dendrímeros , Testes de Sensibilidade Microbiana , Naftalimidas , Poliaminas , Naftalimidas/química , Naftalimidas/farmacologia , Dendrímeros/química , Dendrímeros/farmacologia , Poliaminas/química , Poliaminas/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Fluorescência , Pseudomonas aeruginosa/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Bacillus cereus/efeitos dos fármacos , Luz , Corantes Fluorescentes/química , Espectrometria de Fluorescência
4.
Mikrochim Acta ; 191(6): 310, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38714566

RESUMO

A ratiometric fluorescence sensor has been established based on dual-excitation carbon dots (D-CDs) for the detection of flavonoids (morin is chosen as the typical detecting model for flavonoids). D-CDs were prepared using microwave radiation with o-phenylenediamine and melamine and exhibit controllable dual-excitation behavior through the regulation of their concentration. Remarkably, the short-wavelength excitation of D-CDs can be quenched by morin owing to the inner filter effect, while the long-wavelength excitation remains insensitive, serving as the reference signal. This contributes to the successful design of an excitation-based ratiometric sensor. Based on the distinct and differentiated variation of excitation intensity, morin can be determined from 0.156 to 110 µM with a low detection limit of 0.156 µM. In addition, an intelligent and visually lateral flow sensing device is developed for the determination  of morin content in real samples with satisfying recoveries, which indicates the potential application for human health monitoring.


Assuntos
Carbono , Flavonoides , Limite de Detecção , Nitrogênio , Impressão Tridimensional , Pontos Quânticos , Espectrometria de Fluorescência , Flavonoides/análise , Flavonoides/química , Carbono/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Nitrogênio/química , Corantes Fluorescentes/química , Humanos , Flavonas
5.
Anal Chim Acta ; 1307: 342642, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719399

RESUMO

BACKGROUND: Similar to hypochlorous acid (HClO), hypobromous acid (HBrO) is one of the most notable reactive oxygen species (ROS). Overexpression of HBrO is linked to various diseases causing organ and tissue loss. Due to HBrO's role in the oxidation of micropollutants, real-time monitoring of HBrO in water-based systems is essential. Tetraphenylethylene (TPE)-based organic aggregation-induced emission luminophores (AIEgens) are an emerging category of fluorescent probe materials that have attracted considerable attentions. However, AIE probes are rarely applied to detect HBrO. Developing faster, more precise, and more sensitive AIE probes is thus crucial for detecting biological and environmental HBrO. RESULTS: A small molecule fluorescent probe 4-(1,2,2-triphenylvinyl)benzamidoxime (SWJT-21) was synthesized for the sensitive and selective detection of hypobromous acid (HBrO) based on aggregation-induced emission (AIE). The amidoxime unit of SWJT-21 would undergo an oxidation reaction with HBrO, leading to a structure differentiation between the probe and the product, and therefore the turn-on fluorescence by the AIE effect. The probe could recognize hypobromous acid rapidly (less than 3 s) in high aqueous phase (99 % water) with a turn-on fluorescence response. It was determined that the limit of detection for HBrO was 5.47 nM. Moreover, SWJT-21 demonstrates potential as a test strip for the detection of HBrO. SWJT-21 was also successfully used for the monitoring of HBrO in water samples and for the detection of endogenous/exogenous HBrO in living cells and zebrafish. SIGNIFICANCE: A special AIE fluorescence turn-on probe SWJT-21 based on tetraphenylethylene was designed for detecting HBrO in the environmental and biological systems. This probe has an extremely low detection limit of 5.47 nM and is able to detect HBrO in 99 % aqueous phase in less than 3 s.


Assuntos
Bromatos , Corantes Fluorescentes , Estilbenos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Bromatos/análise , Bromatos/química , Estilbenos/química , Animais , Humanos , Peixe-Zebra , Espectrometria de Fluorescência , Limite de Detecção , Estrutura Molecular
6.
Luminescence ; 39(5): e4738, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719576

RESUMO

A spectrofluorimetric method using fluorescent carbon dots (CDs) was developed for the selective detection of azelnidipine (AZEL) pharmaceutical in the presence of other drugs. In this study, N-doped CDs (N-CDs) were synthesized through a single-step hydrothermal process, using citric acid and urea as precursor materials. The prepared N-CDs showed a highly intense blue fluorescence emission at 447 nm, with a photoluminescence quantum yield of ~21.15% and a fluorescence lifetime of 0.47 ns. The N-CDs showed selective fluorescence quenching in the presence of all three antihypertensive drugs, which was used as a successful detection platform for the analysis of AZEL. The photophysical properties, UV-vis light absorbance, fluorescence emission, and lifetime measurements support the interaction between N-CDs and AZEL, leading to fluorescence quenching of N-CDs as a result of ground-state complex formation followed by a static fluorescence quenching phenomenon. The detection platform showed linearity in the range 10-200 µg/ml (R2 = 0.9837). The developed method was effectively utilized for the quantitative analysis of AZEL in commercially available pharmaceutical tablets, yielding results that closely align with those obtained from the standard method (UV spectroscopy). With a score of 0.76 on the 'Analytical GREEnness (AGREE)' scale, the developed analytical method, incorporating 12 distinct green analytical chemistry components, stands out as an important technique for estimating AZEL.


Assuntos
Ácido Azetidinocarboxílico , Carbono , Di-Hidropiridinas , Pontos Quânticos , Espectrometria de Fluorescência , Di-Hidropiridinas/análise , Di-Hidropiridinas/química , Carbono/química , Ácido Azetidinocarboxílico/análise , Ácido Azetidinocarboxílico/análogos & derivados , Ácido Azetidinocarboxílico/química , Pontos Quânticos/química , Química Verde , Comprimidos/análise , Corantes Fluorescentes/química , Preparações Farmacêuticas/química , Preparações Farmacêuticas/análise , Estrutura Molecular
7.
Luminescence ; 39(5): e4769, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720528

RESUMO

Fluorene nucleus derivatives show great potential for building outstanding fluorescence probes. In this paper, a novel fluorescent probe was developed by reacting with fluorene core with azacyclobutane, which exhibits typical solvation chromogenic effect in solvent. The fluorescence of the probe quenched in highly polar solvent. Based on this phenomenon, a novel fluorescence system for trace water was constructed. The response of this probe was fast (30 s) and sensitive for the detection of trace water in organic solvents, and the detection limit of water content in DMSO reached 0.13%. In addition, the probe can also be made as a test strip combined with homemade portable device and a smartphone for rapid detection of trace water. The luminescence mechanism of the probe is theoretically calculated based on time-contained density functional theory (TDDFT). To showcase its practicality, it has been applied for the detection of trace water in honey and alcohol by dipstick. This method provides a new idea for designing efficient fluorescent probes based on dipstick and mobile phone rapid detection.


Assuntos
Fluorenos , Corantes Fluorescentes , Espectrometria de Fluorescência , Água , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Fluorenos/química , Água/química , Estrutura Molecular , Limite de Detecção , Teoria da Densidade Funcional , Fluorescência , Poluentes Químicos da Água/análise
8.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731924

RESUMO

Förster resonance energy transfer (FRET) spectrometry is a method for determining the quaternary structure of protein oligomers from distributions of FRET efficiencies that are drawn from pixels of fluorescence images of cells expressing the proteins of interest. FRET spectrometry protocols currently rely on obtaining spectrally resolved fluorescence data from intensity-based experiments. Another imaging method, fluorescence lifetime imaging microscopy (FLIM), is a widely used alternative to compute FRET efficiencies for each pixel in an image from the reduction of the fluorescence lifetime of the donors caused by FRET. In FLIM studies of oligomers with different proportions of donors and acceptors, the donor lifetimes may be obtained by fitting the temporally resolved fluorescence decay data with a predetermined number of exponential decay curves. However, this requires knowledge of the number and the relative arrangement of the fluorescent proteins in the sample, which is precisely the goal of FRET spectrometry, thus creating a conundrum that has prevented users of FLIM instruments from performing FRET spectrometry. Here, we describe an attempt to implement FRET spectrometry on temporally resolved fluorescence microscopes by using an integration-based method of computing the FRET efficiency from fluorescence decay curves. This method, which we dubbed time-integrated FRET (or tiFRET), was tested on oligomeric fluorescent protein constructs expressed in the cytoplasm of living cells. The present results show that tiFRET is a promising way of implementing FRET spectrometry and suggest potential instrument adjustments for increasing accuracy and resolution in this kind of study.


Assuntos
Estudos de Viabilidade , Transferência Ressonante de Energia de Fluorescência , Microscopia de Fluorescência , Transferência Ressonante de Energia de Fluorescência/métodos , Microscopia de Fluorescência/métodos , Humanos , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/química , Espectrometria de Fluorescência/métodos , Proteínas Luminescentes/química , Proteínas Luminescentes/metabolismo , Fluorescência
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124317, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38692102

RESUMO

Nitroxyl (HNO), the single-electron reduction product of nitric oxide (NO), has attracted great interest in the treatment of congestive heart failure in clinical trials. In this paper, we describe the first coumarin-based compound N-hydroxy-2-oxo-2H-chromene-6-sulfonamide (CD1) as a dualfunctional HNO donor, which can release both an HNO signaling molecule and a fluorescent reporter. Under physiological conditions (pH 7.4 and 37 °C), the CD1 HNO donor can readily decompose with a half-life of ∼90 min. The corresponding stoichiometry HNO from the CD1 donor was confirmed using both Vitamin B12 and phosphine compound traps. In addition to HNO releasing, specifically, the degradation product 2-oxo-2H-chromene-6-sulfinate (CS1) was generated as a fluorescent marker during the decomposition. Therefore, the HNO amount released in situ can be accurately monitored through fluorescence generation. As compared to the CD1 donor, the fluorescence intensity increased by about 4.9-fold. The concentration limit of detection of HNO releasing was determined to be ∼0.13 µM according to the fluorescence generation of CS1 at physiological conditions. Moreover, the bioimaging of the CD1 donor was demonstrated in the cell culture of HeLa cells, where the intracellular fluorescence signals were observed, inferring the site of HNO release. Finally, we anticipate that this novel coumarin-based CD1 donor opens a new platform for exploring the biology of HNO.


Assuntos
Cumarínicos , Corantes Fluorescentes , Óxidos de Nitrogênio , Cumarínicos/química , Humanos , Corantes Fluorescentes/química , Óxidos de Nitrogênio/química , Óxidos de Nitrogênio/análise , Espectrometria de Fluorescência , Células HeLa
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124349, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38692107

RESUMO

Fluorine (F) is a pivotal element in the formation of human dental and skeletal tissues, and the consumption of water and tea constitutes a significant source of fluoride intake. However, prolonged ingestion of water and tea with excessive fluoride content can lead to fluorosis, which poses a serious health hazard. In this manuscript, a novel turn-on fluorescent probe DCF synthesized by bis-coumarin and tert-butyldiphenylsilane (TBDPS) was introduced for detecting F- in potable water and tea infusions. By leveraging the unique chemical affinity between fluoride and silicon, F- triggers the silicon-oxygen bond cleavage in DCF, culminating in a conspicuous emission of yellow fluorescence. Validated through a succession of optical tests, this probe exhibits remarkable advantages in terms of superior selectivity, a low detection limit, a large Stokes shift, and robust interference resistance when detecting inorganic fluoride. Moreover, it can serve as portable test strips for on-site real-time identification and quantitative analysis of F-. Furthermore, the application of DCF for in-situ monitoring and imaging of F- in zebrafish and soybean root tissues proved its significant value for F- detection in both animal and plant systems. This probe potentially functions as an efficient instrument for delving into the toxic mechanisms of fluoride in physiological processes.


Assuntos
Cumarínicos , Corantes Fluorescentes , Chá , Peixe-Zebra , Corantes Fluorescentes/química , Animais , Cumarínicos/química , Chá/química , Água Potável/análise , Espectrometria de Fluorescência/métodos , Flúor/análise , Flúor/química , Fluoretos/análise , Glycine max/química , Limite de Detecção , Imagem Óptica/métodos
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124357, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38692110

RESUMO

This study described the preparation of an azide covalent organic framework-embedded molecularly imprinted polymers (COFs(azide)@MIPs) platform for urea adsorption and indirect ethyl carbamate (EC) removal from Chinese yellow rice wine (Huangjiu). By modifying the pore surface of COFs using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, COFs(azide) with a high fluorescence quantum yield and particular recognition ability were inventively produced. In order to selectively trap urea, the COFs(azide) were encased in an imprinted shell layer via imprinting technology. With a detection limit (LOD) of 0.016 µg L-1 (R2 = 0.9874), the COFs(azides)@MIPs demonstrated a good linear relationship with urea in the linear range of 0-5 µg L-1. Using real Huangjiu samples, the spiking recovery trials showed the viability of this sensing platform with recoveries ranging from 88.44 % to 109.26 % and an RSD of less than 3.40 %. The Huangjiu processing model system achieved 38.93 % EC reduction by COFs(azides)@MIPs. This research will open up new avenues for the treatment of health problems associated with fermented alcoholic beverages, particularly Huangjiu, while also capturing and removing hazards coming from food.


Assuntos
Polímeros Molecularmente Impressos , Ureia , Uretana , Vinho , Uretana/análise , Uretana/química , Polímeros Molecularmente Impressos/química , Ureia/análise , Ureia/química , Vinho/análise , Espectrometria de Fluorescência/métodos , Azidas/química , Limite de Detecção , Adsorção , Estruturas Metalorgânicas/química , Impressão Molecular/métodos
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124372, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38703408

RESUMO

Here, a novel fluorescence strategy was established for the detection of mirabegron (MBG) sensitively on the basis of hantzsch dihydropyridine synthesis. The developed method adopts turn-on fluorescence of MBG for the first time, permitting its selective determination in spiked human plasma at 486 nm after excitation at 410 nm. The developed method exhibited a good linear range from 0.5 µgmL-1 to 2.0 µgmL-1 with detection and quantification limits of 0.05 and 0.2 (µgmL-1), respectively. The profitable applicability of the developed method in spiked human plasma samples was demonstrated, achieving limit of detection below the previously levels reported by spectroscopic methods, allowing application of the developed method for selective determination of MBG in its tablets and spiked human plasma samples with good recovery.


Assuntos
Acetanilidas , Limite de Detecção , Espectrometria de Fluorescência , Tiazóis , Humanos , Tiazóis/sangue , Tiazóis/química , Acetanilidas/sangue , Acetanilidas/química , Espectrometria de Fluorescência/métodos , Reprodutibilidade dos Testes
13.
Mikrochim Acta ; 191(6): 303, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709340

RESUMO

A platform was designed based on Fe3O4 and CsPbBr3@SiO2 for integrated magnetic enrichment-fluorescence detection of Salmonella typhimurium, which significantly simplifies the detection process and enhances the working efficiency. Fe3O4 served as a magnetic enrichment unit for the capture of S. typhimurium. CsPbBr3@SiO2 was employed as a fluorescence-sensing unit for quantitative signal output, where SiO2 was introduced to strengthen the stability of CsPbBr3, improve its biomodificability, and prevent lead leakage. More importantly, the SiO2 shell shows neglectable absorption or scattering towards fluorescence, making the CsPbBr3@SiO2 exhibit a high quantum yield of 74.4%. After magnetic enrichment, the decreasing rate of the fluorescence emission intensity of the CsPbBr3@SiO2 supernatant at 527 nm under excitation light at UV 365 nm showed a strong linear correlation with S. typhimurium concentration of 1 × 102~1 × 108 CFU∙mL-1, and the limit of detection (LOD) reached 12.72 CFU∙mL-1. This platform has demonstrated outstanding stability, reproducibility, and resistance to interference, which provides an alternative for convenient and quantitative detection of S. typhimurium.


Assuntos
Corantes Fluorescentes , Limite de Detecção , Salmonella typhimurium , Dióxido de Silício , Salmonella typhimurium/isolamento & purificação , Dióxido de Silício/química , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Chumbo/química , Sistemas Automatizados de Assistência Junto ao Leito , Sulfetos/química , Nanopartículas de Magnetita/química , Humanos
14.
Mikrochim Acta ; 191(6): 299, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709371

RESUMO

Gold nanoclusters are a smart platform for sensing potassium ions (K+). They have been synthesized using bovine serum albumin (BSA) and valinomycin (Val) to protect and cap the nanoclusters. The nanoclusters (Val-AuNCs) produced have a red emission at 616 nm under excitation with 470 nm. In the presence of K+, the valinomycin polar groups switch to the molecule's interior by complexing with K+, forming a bracelet structure, and being surrounded by the hydrophobic exterior conformation. This structure allows a proposed fluorometric method for detecting K+ by switching between the Val-AuNCs' hydrophilicity and hydrophobicity, which induces the aggregation of gold nanoclusters. As a result, significant quenching is seen in fluorescence after adding K+. The quenching in fluorescence in the presence of K+ is attributed to the aggregation mechanism. This sensing technique provides a highly precise and selective sensing method for K+ in the range 0.78 to 8 µM with LOD equal to 233 nM. The selectivity of Val-AuNCs toward K+ ions was investigated compared to other ions. Furthermore, the Val-AuNCs have novel possibilities as favorable sensor candidates for various imaging applications. Our detection technique was validated by determining K+ ions in postmortem vitreous humor samples, which yielded promising results.


Assuntos
Corantes Fluorescentes , Ouro , Nanopartículas Metálicas , Potássio , Soroalbumina Bovina , Valinomicina , Ouro/química , Valinomicina/química , Potássio/análise , Potássio/química , Nanopartículas Metálicas/química , Soroalbumina Bovina/química , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Animais , Interações Hidrofóbicas e Hidrofílicas , Bovinos
15.
Mikrochim Acta ; 191(6): 304, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710810

RESUMO

Dual-emissive fluorescence probes were designed by integrating porphyrin into the frameworks of UiO-66 for ratiometric fluorescence sensing of amoxicillin (AMX). Porphyrin integrated UiO-66 showed dual emission in the blue and red region. AMX resulted in the quenching of blue fluorescence component, attributable to the charge neutralization and hydrogen bonds induced energy transfer. AMX was detected using (F438/F654) as output signals. Two linear relationships were observed (from 10 to 1000 nM and 1 to 100 µM), with a limit of detection of 27 nM. The porphyrin integrated UiO-66 probe was used to detect AMX in practical samples. This work widens the road for the development of dual/multiple emissive fluorescence sensors for analytical applications, providing materials and theoretical supporting for food, environmental, and human safety.


Assuntos
Amoxicilina , Antibacterianos , Corantes Fluorescentes , Leite , Porfirinas , Espectrometria de Fluorescência , Leite/química , Porfirinas/química , Antibacterianos/análise , Antibacterianos/química , Amoxicilina/análise , Amoxicilina/química , Corantes Fluorescentes/química , Animais , Espectrometria de Fluorescência/métodos , Limite de Detecção , Estruturas Metalorgânicas/química , Resíduos de Drogas/análise , Contaminação de Alimentos/análise
16.
Anal Chim Acta ; 1306: 342581, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692785

RESUMO

Cancer detection is still a major challenge in public health. Identification of oncogene is the first step toward solving this problem. Studies have revealed that various cancers are associated with miRNA expression. Therefore, the sensitive detection of miRNA is substantially important to solve the cancer problem. In this study, let-7a, a representative substance of miRNA, was selected as the detection target. With the assistance of magnetic beads commonly used in biosensors and self-synthesized graphene oxide materials, specificity and sensitivity detection of the target gene let-7a were achieved via protease-free signal amplification. The limit of detection (LOD) was as low as 15.015pM. The fluorescence signal intensity showed a good linear relationship with the logarithm of let-7a concentration. The biosensor could also detect let-7a in complex human serum samples. Overall, this fluorescent biosensor is not only simple to operate, but also strongly specificity to detect let-7a. Therefore, it has substantial potential for application in the early diagnosis of clinical medicine and biological research.


Assuntos
Técnicas Biossensoriais , Grafite , Limite de Detecção , MicroRNAs , Técnicas Biossensoriais/métodos , Humanos , Grafite/química , MicroRNAs/análise , MicroRNAs/sangue , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Neoplasias/diagnóstico , Neoplasias/sangue
17.
Anal Chim Acta ; 1306: 342586, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692787

RESUMO

BACKGROUND: Early prostatic cancer (PCa) diagnosis significantly improves the chances of successful treatment and enhances patient survival rates. Traditional enzyme cascade-based early cancer detection methods offer efficiency and signal amplification but are limited by cost, complexity, and enzyme dependency, affecting stability and practicality. Meanwhile, sarcosine (Sar) is commonly considered a biomarker for PCa development. It is essential to develop a Sar detection method based on cascade reactions, which should be efficient, low skill requirement, and suitable for on-site testing. RESULTS: To address this, our study introduces the synthesis of organic-inorganic self-assembled nanoflowers to optimize existing detection methods. The Sar oxidase (SOX)-inorganic hybrid nanoflowers (Cu3(PO4)2:Ce@SOX) possess inherent fluorescent properties and excellent peroxidase activity, coupled with efficient enzyme loading. Based on this, we have developed a dual-mode multi-enzyme cascade nanoplatform combining fluorescence and colorimetric methods for the detection of Sar. The encapsulation yield of Cu3(PO4)2:Ce@SOX reaches 84.5 %, exhibiting a remarkable enhancement in catalytic activity by 1.26-1.29 fold compared to free SOX. The present study employing a dual-signal mechanism encompasses 'turn-off' fluorescence signals ranging from 0.5 µM to 60 µM, with a detection limit of 0.226 µM, and 'turn-on' colorimetric signals ranging from 0.18 µM to 60 µM, with a detection limit of 0.120 µM. SIGNIFICANCE: Furthermore, our study developed an intelligent smartphone sensor system utilizing cotton swabs for real-time analysis of Sar without additional instruments. The nano-platform exhibits exceptional repeatability and stability, rendering it well-suited for detecting Sar in authentic human urine samples. This innovation allows for immediate analysis, offering valuable insights for portable and efficient biosensors applicable to Sar and other analytes.


Assuntos
Colorimetria , Oxirredução , Sarcosina , Smartphone , Sarcosina/urina , Sarcosina/análise , Sarcosina/química , Humanos , Nanoestruturas/química , Limite de Detecção , Espectrometria de Fluorescência , Neoplasias da Próstata/diagnóstico , Fluorescência , Técnicas Biossensoriais , Sarcosina Oxidase/química
18.
Luminescence ; 39(5): e4743, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692854

RESUMO

A unique luminescent lanthanide metal-organic framework (LnMOF)-based fluorescence detection platform was utilized to achieve sensitive detection of vomitoxin (VT) and oxytetracycline hydrochloride (OTC-HCL) without the use of antibodies or biomolecular modifications. The sensor had a fluorescence quenching constant of 9.74 × 106 M-1 and a low detection limit of 0.68 nM for vomitoxin. Notably, this is the first example of a Tb-MOF sensor for fluorescence detection of vomitoxin. We further investigated its response to two mycotoxins, aflatoxin B1 and ochratoxin A, and found that their Stern-Volmer fluorescence quenching constants were lower than those of VT. In addition, the fluorescence sensor realized sensitive detection of OTC-HCL with a detection limit of 0.039 µM. In conclusion, the method has great potential as a sensitive and simple technique to detect VT and OTC-HCL in water.


Assuntos
Estruturas Metalorgânicas , Oxitetraciclina , Térbio , Oxitetraciclina/análise , Oxitetraciclina/química , Térbio/química , Estruturas Metalorgânicas/química , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Água/química , Fluorescência , Poluentes Químicos da Água/análise
19.
Luminescence ; 39(5): e4752, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38697778

RESUMO

Prucalopride (PCD), is a modern medication approved by the United States in 2018 to alleviate constipation caused by motility issues. PCD demonstrates a strong affinity and selectivity toward the 5-HT4 receptor. The study here introduces a feasible, direct, non-extractive, and affordable pathway for PCD analytical tracking. The fluorimetric study is based on the on-off effect on the emission amplitude of fluorone-based dye (pyrosin B). In a one-pot experiment, the complex between PCD and pyrosin B is formed instantly in an acidic medium. Correlation between decreased pyrosin B emission and PCD concentrations provides a linear calibration plot from 50 to 900 ng/mL. PCD-dye complex system affecting variables were meticulously tuned. The values of the estimated limit of quantitation and limit of detection for the current methodology were 47.5 and 15.7 ng/mL, respectively. Conformity of the strategy validity was achieved by a comprehensive study of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use criteria. The method was convincingly applied for PCD assay in tablets and content uniformity investigation. Furthermore, PCD tracking in the spiked biological fluid was applied. Finally, the method uses distilled water as dispersing medium which rise accommodation with the green chemistry principle.


Assuntos
Benzofuranos , Corantes Fluorescentes , Benzofuranos/química , Benzofuranos/análise , Corantes Fluorescentes/química , Humanos , Espectrometria de Fluorescência , Estrutura Molecular , Limite de Detecção
20.
Sci Rep ; 14(1): 10066, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698009

RESUMO

The global threat of antibiotic resistance has increased the importance of the detection of antibiotics. Conventional methods to detect antibiotics are time-consuming and require expensive specialized equipment. Here, we present a simple and rapid biosensor for detecting ampicillin, a commonly used antibiotic. Our method is based on the fluorescent properties of chitosan-coated Mn-doped ZnS micromaterials combined with the ß-lactamase enzyme. The biosensors exhibited the highest sensitivity in a linear working range of 13.1-72.2 pM with a limit of detection of 8.24 pM in deionized water. In addition, due to the biological specificity of ß-lactamase, the proposed sensors have demonstrated high selectivity over penicillin, tetracycline, and glucose through the enhancing and quenching effects at wavelengths of 510 nm and 614 nm, respectively. These proposed sensors also showed promising results when tested in various matrices, including tap water, bottled water, and milk. Our work reports for the first time the cost-effective (Mn:ZnS)Chitosan micromaterial was used for ampicillin detection. The results will facilitate the monitoring of antibiotics in clinical and environmental contexts.


Assuntos
Ampicilina , Técnicas Biossensoriais , Quitosana , Manganês , Sulfetos , Compostos de Zinco , Ampicilina/análise , Ampicilina/química , Quitosana/química , Técnicas Biossensoriais/métodos , Compostos de Zinco/química , Manganês/química , Sulfetos/química , Antibacterianos/análise , Antibacterianos/química , beta-Lactamases/análise , beta-Lactamases/metabolismo , beta-Lactamases/química , Leite/química , Limite de Detecção , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Animais
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