Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros













Base de datos
Intervalo de año de publicación
1.
Luminescence ; 39(6): e4801, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38855811

RESUMEN

Atopic dermatitis (AD) is a persistent, inflammatory skin condition that impacts approximately 15 to 20% of children and 1 to 3% of adults globally. Common skin manifestations include papules, papulovesicular, and brown or red patches with swelling, crusting, and flaking. Therefore, the drug abrocitinib (ABR) was approved by the US FDA as an oral treatment for atopic dermatitis. The present study outlines the development of innovative, thermostable, and pH-stable organic solvent-free nitrogen-doped carbon dots (N@CQDs) synthesized through a one-step method for evaluating ABR with a notable quantum yield of 33.84% to minimize the use of organic solvents. Their cost-effectiveness, eco-friendly characteristics, and outstanding photocatalytic properties have established them as a promising alternative to conventional luminescent techniques like fluorescent dyes and luminous derivatization technique. The reaction of ABR with N@CQDs led to a significant decrease in the luminescent response of the produced green and stable carbon quantum dots at 513 nm. The detection range was determined to be 1.0-150.0 ng mL-1, with a lower limit of quantitation (LOQ) equal to 0.52 ng mL-1 based on the linear graph. The green method effectively used for analysis of ABR in pharmaceutical tablets and pharmacokinetic study with high sensitivity.


Asunto(s)
Carbono , Nitrógeno , Puntos Cuánticos , Puntos Cuánticos/química , Carbono/química , Nitrógeno/química , Humanos , Pirimidinas/química , Pirimidinas/sangre , Pirimidinas/síntesis química , Fluorometría , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Solventes/química , Estructura Molecular
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124470, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-38761476

RESUMEN

Recently, nanomaterials have attracted a lot of attention due to their potential as effective fluorescent nano-sensor probes. They were distinguishing substitutes for other luminescent techniques, such as fluorescent dyes and luminous derivatization, because of their affordability, environmental friendliness, and special photocatalytic properties. In the suggested work, a straightforward method was used to create boron and nitrogen carbon dots (B@CDs) with a good quantum yield value of 31.15 % utilizing boric acid and di-sodium EDTA. For the purpose of characterizing QDs, a variety of instruments were employed, such as transmission electron microscopy, fluorescence spectroscopy, X-ray FTIR, and UV-VIS spectroscopy. Nebivolol (NEB) is a cardiovascular medication used globally to treat congestive heart failure and hypertension, is in the meantime. For this reason, a brand-new, environmentally friendly analytical technique was created to determine the amount of human plasma, uniformity test, and commercial nebivolol (NEB) tablets. After gradually adding NEB, the response of B@CQDs was enhanced at 438 nm (excitation at 371 nm). The calibration graph ranged between 20 and 500 ng mL-1 with a quantification limit (LOQ) of 2.50 ng mL-1 and a detection limit (LOD) of 0.82 ng mL-1.


Asunto(s)
Boro , Carbono , Nebivolol , Puntos Cuánticos , Nebivolol/sangre , Nebivolol/análisis , Humanos , Carbono/química , Puntos Cuánticos/química , Boro/química , Tecnología Química Verde/métodos , Espectrometría de Fluorescencia/métodos , Límite de Detección , Espectroscopía Infrarroja por Transformada de Fourier , Comprimidos , Espectrofotometría Ultravioleta
4.
RSC Adv ; 14(15): 10445-10451, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38567336

RESUMEN

Avapritinib (AVA) is the first medication authorized by the US-FDA in 2020 for the management of gastrointestinal stromal tumours (GISTs) that can't be treated by surgery. Cancer is among the most common causes of death worldwide and is the second most common cause of death after cardiovascular disease. Therefore, a quick, easy, sensitive, and straightforward fluorimetric approach was used to analyse AVA in pharmaceutical materials and blood plasma (pharmacokinetic). The suggested technique relies on 2% sodium dodecyl sulphate (SDS, pH 4) micellar system augmentation of the fluorescence of the tested drug. The technique demonstrated high relative fluorescence intensity (RFI) at 430 nm after excitation at 340 nm. Concentrations ranging from 20.0-400.0 ng mL-1 with a limit of quantitation of 9.47 ng mL-1 were used to obtain luminescence data for the studied medicine. In addition, the quantum yield of the AVA fluorescence was increased with the gradual addition of a surfactant at a concentration above its critical micellar level. This knowledge has been exploited to enhance the effectiveness of a spectrofluorometric technique for the estimation of AVA in human plasma (98.95 ± 1.22%) and uniformity tests with greenness assessments. The conditions for enhanced fluorescence were optimized and fully validated using US-FDA and International Conference on Harmonization (ICH) rules. This innovative strategy was expanded for AVA stability research in human plasma across various circumstances. This approach is an eco-friendly solution compared to traditional testing methods that use hazardous chemicals.

5.
Appl Spectrosc ; 78(3): 329-339, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38166449

RESUMEN

Terbium- and nitrogen-doped carbon quantum dots (Tb,N@CQDs) were greenly created employing microwave synthesis from plum juice with terbium nitrate. The synthesis of Tb,N@CQDs was fast (7 min) with a high quantum yield (35.44%). Tb,N@CQDs were fully characterized using transmission electron microscopy, Zeta potential analysis, fluorescence, and ultraviolet spectroscopy. Omadacycline (OMC) is a broad-spectrum tetracycline that has been recently approved by the United States Food and Drug Act (FDA) in October 2018. OMC is the first oral aminomethylcycline class antibiotic drug that was authorized for the treatment of acute skin structure infections and community-acquired pneumonia. Tb,N@CQDs exhibited emission at 440 nm after excitation at 360 nm, where their fluorescence intensity showed a reduction upon addition of OMC. The experimental parameters were further studied and optimized. The linear range was between 40 and 60 parts per billion (ppb), with (limit of quantitation) equal to 34.78 ppb. The proposed approach was validated for bioanalytical purposes using FDA guidelines and proved to be straightforward, cheap, highly sensitive, and very selective, which can be used in clinical studies. The developed approach proved to be green using some current assessment metrics and was applied successfully for the determination of OMC in human plasma, milk, and pharmaceutical formulations as well as pharmacokinetic study.


Asunto(s)
Puntos Cuánticos , Humanos , Puntos Cuánticos/química , Terbio/química , Tetraciclinas , Carbono/química , Nitrógeno
6.
Anal Bioanal Chem ; 415(22): 5529-5538, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37432444

RESUMEN

Copper (Cu) plays a role in maintaining healthy nerve cells and the immune system. Osteoporosis is a high-risk factor for Cu deficiency. In the proposed research, unique green, fluorescent cysteine-doped MnO2 quantum dots (Cys@MnO2 QDs) were synthesized and assessed for the determination of Cu in different food and hair samples. The developed quantum dots were synthesized with the help of cysteine using a straightforward ultrasonic approach to create 3D fluorescent Cys@MnO2 QDs. The resulting QDs' morphological and optical characteristics were carefully characterized. By adding Cu ions, the intensity of fluorescence for the produced Cys@MnO2 QDs was found to be dramatically reduced. Additionally, the applicability of Cys@MnO2 QDs as a new luminous nanoprobe was found to be strengthened by the quenching effect grounded on the Cu-S bonding. The concentrations of Cu2+ ions were estimated within the range of 0.06 to 7.00 µg mL-1, with limit of quantitation equal to 33.33 ng mL-1 and detection limit equal to 10.97 ng mL-1. The Cys@MnO2 QD technique was applied successfully for the quantification of Cu in a variety of foods, including chicken meat, turkey, and tinned fish, as well as in human hair samples. The chance that this novel technique could be a useful tool for figuring out the amount of cysteine in bio-samples is increased by the sensing system's remarkable advantages, which include being rapid, simple, and economical.


Asunto(s)
Puntos Cuánticos , Cobre/química , Puntos Cuánticos/química , Cisteína/química , Espectrometría de Fluorescencia/métodos , Factores de Tiempo
7.
Luminescence ; 38(9): 1632-1638, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37417422

RESUMEN

Avapritinib (AVP) was the first precision drug to be approved by the US Food and Drug Administration (FDA) in 2020 for patients suffering from metastatic gastrointestinal stromal tumors (GISTs) and progressive systemic mastocytosis. The analysis of AVP in pharmaceutical tablets and human plasma was then carried out using a fast, efficient, sensitive, and simple fluorimetric method using a fluorescamine reagent. The procedure is based on the interaction between fluorescamine as a fluorogenic reagent and the primary aliphatic amine moiety in AVP using borate buffer solution at pH 8.8. The produced fluorescence was measured at 465 nm (Excitation at 395 nm). The calibration graph's linearity range was discovered to be 45.00-500.0 ng mL-1 . Utilizing the International Council for Harmonization (ICH) and US-FDA recommendations, the research technique was validated and bioanalytically validated. The proposed approach was effectively employed for determining the stated pharmaceuticals in plasma with a high percentage of recovery ranging from 96.87 to 98.09 and pharmaceutical formulations with a percentage of recovery equal to 102.11% ± 1.05%. In addition, the study was extended to a pharmacokinetic study of AVP with 20 human volunteers as a step for AVP management in therapeutic cancer centers.


Asunto(s)
Fluorescamina , Humanos , Indicadores y Reactivos , Preparaciones Farmacéuticas/análisis , Espectrometría de Fluorescencia/métodos
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 298: 122808, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37163899

RESUMEN

Type 2 diabetes can be cured by using tradjenta (also known as Linagliptin), a new therapeutic drug that is an inhibitor of the dipeptidyl peptidase-4 enzyme. Tradjenta is administered orally alone or in combination with metiguanide or empagliflozin. An easy and specific fluorimetric analysis of Tradjenta was developed and demonstrated in the present investigation. The Hantzsch reaction method, which generates a fluorescent dihydropyridine derivative, is the basis of this assay. In a Toerell-Stenhagen buffered solution, the unsubstituted amine group of Tradjenta interacted with 2,4-Pentadione/Oxomethane. Spectrofluorimetry was utilized for this investigation at an excitation/emission wavelength of 421/480 nm. When comparing the Tradjenta concentration to the tracked fluorimetric signal, the method revealed linearity over the concentration range of 0.05 to 1.2 µg/mL. By strictly altering system parameters and analyzing the validation factors following International Council for Harmonisation (ICH) requirements, the outcomes were achieved. Finally, the proposed approach was successfully applied to assay the drug not only in its raw form and prescribed formulations but also to evaluate the tablet's uniformity of content.


Asunto(s)
Diabetes Mellitus Tipo 2 , Linagliptina , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Colorantes Fluorescentes , Fluorometría , Espectrometría de Fluorescencia/métodos
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 292: 122399, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36724684

RESUMEN

The purpose of the present work was to establish a fast and convenient strategy for lomefloxacin analysis using a fluorimetric approach. The methodology was based on the complex formation of the drug with aluminum ion to give a product having high fluorescence. Adding sodium dodecyl sulfate led to further boosting the intensity of fluorescence which was recorded at 429 nm after excitation at 332 nm. The relationship of emission intensity with lomefloxacin concentration was linear at 10-130 ng mL-1 with a correlation coefficient of 0.9996. The quantitation limit was 11.4 ng mL-1 and detection limit was 3.8 ng mL-1. The reaction conditions were carefully studied which included the pH, buffer type, its concentration, the type and concentration of surfactant and the diluting solvent. The method was utilized to quantify the aforementioned drug in tablet formulations and in real human plasma with high accuracy and reliability.


Asunto(s)
Fluoroquinolonas , Metales , Humanos , Espectrometría de Fluorescencia/métodos , Reproducibilidad de los Resultados , Fluoroquinolonas/análisis , Solventes
10.
Luminescence ; 38(2): 166-175, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36609821

RESUMEN

Mitoxantrone (MXN) is a synthetic anthracenedione oncogenic therapy. It is often prescribed as an anticancer agent to manage a variety of cancers. A green, fast, and easy fluorimetric technique for the assay of MXN as a topoisomerase type II enzyme suppressor. An investigation of MXN's fluorescence behavior in various media and solvents constituted the basis for this new technique. Methanol was shown to enhance the intrinsic fluorescence considerably. After excitation at 610 nm, the highest fluorescence intensity was found at 675 nm. Various experimental parameters, such as media, solvents, and pH levels, were tested and adjusted. ICH (International Conference on Harmonization) guidelines were followed when validating procedures. It was possible to achieve linearity in the 0.02-1.50 µg ml-1 with the method. The sensitivity (in terms of limit of detection and limit of quantification) was 0.003 and 0.008 µg ml-1 , indicating low toxicity. As a result, the current technology has a remarkable recovery for detecting residues in diverse bodily fluids. Also, the quantum yield was estimated for the designed system. Finally, the method was rated by eco-scale scoring.


Asunto(s)
Antineoplásicos , Mitoxantrona , Límite de Detección , Espectrometría de Fluorescencia/métodos , Solventes/química
11.
Luminescence ; 38(2): 145-151, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36579943

RESUMEN

Mercury (Hg2+ ) is a natural element present in foods such as fish, water and soil. Exposure to mercury leads to severe toxic effects on the nervous, digestive, and immune systems. Here, a novel, green, and environmentally friendly fluorescent probe decorated with cysteine/MnO2 quantum dots (Cys@MnO2 QDs) was synthesized. This synthesis was carried out using a simple ultrasound technique with the aid of cysteine for fabricating Cys@MnO2 QDs to estimate Hg levels in fish and water samples. In this morphological study, Cys@MnO2 QDs were fully characterized using high-resolution transmission electron microscopy, zeta potential analysis, fluorescence, ultraviolet-visible and infrared spectroscopy. The fluorescence of the synthesized Cys@MnO2 QDs was significantly quenched by gradually increasing the Hg(II) concentration. The quenching mechanism based on the Hg-S bonds strengthened the utility of the Cys@MnO2 QDs as a novel luminescent nanoprobe. The estimation of Hg was linear in the concentration range 0.7-100.0 ng mL-1 with a limit of quantitation equal to 0.30 ng mL-1 . The Cys@MnO2 QDs are fluorescent probes with various benefits such as speed, ease of use, cost- effective, and being environmentally friendly; they are easily applied in food manufacturing and for public health improvement.


Asunto(s)
Mercurio , Puntos Cuánticos , Animales , Cisteína/análisis , Agua/química , Óxidos , Espectrometría de Fluorescencia/métodos , Compuestos de Manganeso , Mercurio/análisis , Puntos Cuánticos/química , Colorantes Fluorescentes/química
12.
J Fluoresc ; 33(3): 1101-1110, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36576682

RESUMEN

The neuro-stimulant anti-narcoleptic drug as modafinil (MOD) is used to treatment neurological conditions caused by COVID-19. MOD was used to treatment narcolepsy, shift-work sleep disorder, and obstructive sleep apnea-related sleepiness. So, an innovative, quick, economical, selective, and ecologically friendly procedure was carried out. A highly sensitive N@CQDs technique was created from green Eruca sativa leaves in about 4 min using microwave synthesis at 700 w. The quantum yield of the synthesized N@CQDs was found to be 41.39%. By increasing the concentration of MOD, the quantum dots' fluorescence intensity was gradually quenched. After being excited at 445 nm, the fluorescence reading was recorded at 515 nm. The linear range was found to be in the range 50 - 700 ng mL-1 with lower limit of quantitation (LOQ) equal to 45.00 ng mL-1. The current method was fully validated and bio analytically according to (US-FDA and ICH) guidelines. Full characterization of the N@CQDs has been conducted by high resolution transmission electron microscope (HRTEM), Zeta potential measurement, fluorescence, UV-VIS, and FTIR spectroscopy. Various experimental variables including pH, QDs concentration and the reaction time were optimized. The proposed study is simply implemented for the therapeutic drug monitoring system (TDMS) and various clinical laboratories for further pharmacokinetic research.


Asunto(s)
COVID-19 , Puntos Cuánticos , Humanos , Puntos Cuánticos/química , Modafinilo , Carbono/química , Nitrógeno/química , Microondas , Colorantes Fluorescentes/química
13.
BMC Chem ; 16(1): 58, 2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35922841

RESUMEN

Elagolix (ELX) is an orally administered non-peptidic GnRH antagonist that has been approved by the Food and Drug Administration in 2018 for the treatment of endometriosis pain. A sensitive and selective method for estimating elagolix (ELX) in human plasma and content uniformity was developed and validated. The spectrofluorimetric technique was used to investigate ELX utilizing boron-doped carbon quantum dots (B@CQDs). After gradually adding ELX, the quantum dots fluorescence was enhanced with LOQ of 1.74 ng mL-1, the calibration curve between ELX and corresponding fluorescence intensity was found over a range of 4-100 ng mL-1. The method was successfully applied in real human plasma with pharmacokinetic study and content uniformity test. The pharmacokinetic parameters as Cmax were found to be 570 ± 5.32 ng. mL-1 after 1 h, t1/2 was found to be 6.50 h, and AUC was found to be 1290 ± 30.33 ng. h. mL-1. B@CQDs were characterized using variety of instruments. The strategy is simple to implement in clinical labs and therapeutic drug monitoring systems.

14.
J Fluoresc ; 32(5): 1725-1732, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35670919

RESUMEN

Vonoprazan (VON) has been approved recently via US-FDA in 2015 as the first in class of potassium competitive acid blocker group. VON is used for management of GIT ulcer, reflux esophagitis and for eradication of Helicobacter pylori. So, the first spectrofluorimetric method was developed for estimation of VON in real human plasma and content uniformity test. The fluorimetric methodology based on reaction of secondary amine group in VON with benzofurazan (0.05% w/v NBD-Cl) reagent as nucleophilic substitution reaction in alkaline medium (0.1 M borate buffer pH 8.2) to produce highly fluorescent product measure at 530 nm after excitation at 465 nm. The linear calibration range was found 15 to 200 ng mL-1 with lower limit of quantitation (LOQ) equal to 8.57 ng mL-1. The method was successfully applied for estimation of VON in pharmacokinetic (PK) and content uniformity studies. The maximum plasma concentration was found to be (Cmax) 71.03 ng mL-1 after maximum time (tmax) equal to 1.5 ± 0.15 h. The presented strategy also applied to ensure concentration of drug in each tablet using content uniformity test with high percent of recovery 100.05 ± 0.66. The proposed method was established for clinical laboratories and therapeutic drug monitoring studies.


Asunto(s)
Pirroles , Sulfonamidas , Fluorometría , Humanos , Espectrometría de Fluorescencia/métodos
15.
Luminescence ; 37(7): 1215-1222, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35582967

RESUMEN

The interaction of venlafaxine hydrochloride (VLX) with erythrosine B was investigated using a resonance Rayleigh scattering (RRS) spectroscopic technique. In acetate buffer (pH 3.4), erythrosine B reacted with VLX to form a 1:1 ion-pair complex with concomitant enhancement in RRS intensity that was measured at 330 nm. In addition, the stability constant and the change in free energy of the reaction were estimated. Based on this interaction a new method was developed for a sensitive VLX analysis using erythrosine B as a probe. The results indicated that this method had good selectivity in the presence of coexisting compounds. The scattering intensity (ΔIRRS ) was linearly dependent on VLX concentration over the range 0.04-1.0 µg ml-1 with a determination coefficient (r) of 0.9998. The limit of detection and limit of quantitation were 0.01 and 0.03 µg ml-1 , respectively. This method could be suitably used for analysis of VLX in pharmaceutical capsules and human plasma.


Asunto(s)
Eritrosina , Eritrosina/química , Humanos , Preparaciones Farmacéuticas , Dispersión de Radiación , Análisis Espectral/métodos , Clorhidrato de Venlafaxina
16.
Complex Intell Systems ; 8(6): 4897-4909, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35496326

RESUMEN

The increase in people's use of mobile messaging services has led to the spread of social engineering attacks like phishing, considering that spam text is one of the main factors in the dissemination of phishing attacks to steal sensitive data such as credit cards and passwords. In addition, rumors and incorrect medical information regarding the COVID-19 pandemic are widely shared on social media leading to people's fear and confusion. Thus, filtering spam content is vital to reduce risks and threats. Previous studies relied on machine learning and deep learning approaches for spam classification, but these approaches have two limitations. Machine learning models require manual feature engineering, whereas deep neural networks require a high computational cost. This paper introduces a dynamic deep ensemble model for spam detection that adjusts its complexity and extracts features automatically. The proposed model utilizes convolutional and pooling layers for feature extraction along with base classifiers such as random forests and extremely randomized trees for classifying texts into spam or legitimate ones. Moreover, the model employs ensemble learning procedures like boosting and bagging. As a result, the model achieved high precision, recall, f1-score and accuracy of 98.38%.

17.
Luminescence ; 37(8): 1259-1266, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35586926

RESUMEN

Tyramine (TYM) is catecholamine releasing compound and TYM rich food causes hypertensive crisis due to a combination with monoamine oxidase inhibitor (MAOIs). Therefore, analysis of TYM in TYM rich food as (old cheese, cured meat, sausage, pickled olive and canned fish) and the environment is essential for hypertensive patients and to improvement of food industries. In this work, TYM was analyzed in different types of food using novel green synthesis carbon dots from Ficus carica (fig fruits). The gradual addition of TYM to polyamine carbon quantum dots (PA@CQDs) led to enhancement of the quantum dots fluorescence due to formation of hydrogen bonding between quantum dots and TYM. The calibration graph was plotted in the range 5-400 ng mL-1 . The method was applied for the determination of TYM in different types of food as old cheese, cured meat, sausage, pickled olive and canned fish. The lower limit of quantitation (LOQ) was found to be 1.68 ng mL-1 . The method was successfully applied for the quantification of TYM in varying types of food with high sensitivity and high economic effect due to the reusability of the quantum dots. The optical and morphological characters of quantum dots were studied carefully.


Asunto(s)
Ficus , Puntos Cuánticos , Animales , Carbono/química , Colorantes Fluorescentes/química , Puntos Cuánticos/química , Tiramina
18.
Food Chem ; 349: 129160, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33550018

RESUMEN

Indigo carmine (IC) dye is hazardous and allergenic for humans even though it has been excessively used in a wide range of industries. Therefore, the quantitative determination of IC is still challenging. Herein, for the first time, we have developed fluorometric and colorimetric dual-mode nanoprobe derived from the ion-pair association complex between the negatively charged IC and positively charged N@C-dots in pH = 3.0. Consequently, the binding between N@C-dots and IC resulted in cyan blue and quenching of N@C-dots fluorescence. The dependence of the fluorescence response on IC concentrations was linear over the range of 0.73-10.0 µM (R2 = 0.9989) with LOD of 0.24 µM. On the other hand, the linearity of the colorimetric method ranged from 9.97 to 80.0 µM (R2 = 0.9986) with LOD of 3.3 µM. The sensor was applied for estimation of IC in fruit juice and soft drink without the need for exhaustive extraction steps.


Asunto(s)
Bebidas/análisis , Carbono/química , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Carmin de Índigo/análisis , Límite de Detección , Nitrógeno/química , Colorimetría , Fluorometría , Humanos
19.
Anal Bioanal Chem ; 412(6): 1353-1363, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31900540

RESUMEN

The study of biologically important Cu2+ and S2- ions has drawn great attention in the recent years since an abnormal level of these ions is an indication for health impairment. Therefore, a reliable strategy for effective fluorescence determination of Cu2+ and S2- ions was developed. Simply, the method based on economical plant-dependent thermolysis procedure for efficient green synthesis of water dispersible luminescent polyamine-based carbon dots (PA@C-dots) utilizes Vitis vinifera juice as precursor with a high quantum yield (32.1%) and good photo-stability. The fluorescent PA@C-dots were characterized by different spectroscopical, physical, and structural techniques. Furthermore, the synthesized PA@C-dots can be used as an efficient dual functional fluorescent probe for the sensitive and selective estimation of Cu2+ and S2- ions. The incorporation of Cu2+ ions and their adsorption on the surface of PA@C-dot skeleton leads to the respectable fluorescence quenching of C-dots (turn-off mode). The Cu2+-PA@C-dot was found to be sensitive to S2- ions. The addition of S2- recovers the fluorescence (turn-on mode) of Cu2+-PA@C-dots, thanks to its capacity for withdrawing Cu2+ from the shell of PA@C-dots. Fluorescence quenching in the range of 0.07-60 µM Cu2+ was obtained with LOD and LOQ of 0.02 and 0.066 µM, respectively. Sulfide detection provides linearity in the range of 0.8 to 95 µM with LOD and LOQ of 0.24 and 0.79 µM, respectively. The optimal excitation and emission wavelengths for all experiments are 435 nm and 498 nm, respectively. Experiment results elucidate that the proposed method is suitable for Cu2+and S2- ion detection in environmental water samples. Graphical abstract Green synthesis of polyamine-functionalized nanoprobe by thermolysis method from plant source as bifunctional sensing platform for determination of Cu2+ and S2- in environmental water samples.


Asunto(s)
Carbono/química , Cobre/análisis , Tecnología Química Verde , Poliaminas/química , Puntos Cuánticos/química , Azufre/análisis , Límite de Detección , Microscopía Electrónica de Transmisión , Difracción de Polvo , Análisis Espectral/métodos , Vitis/química
20.
RSC Adv ; 10(30): 17506-17514, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35515596

RESUMEN

In recent decades, H2O2 has been promoted as a health indicator because its moderate to high levels can cause some health problems. Herein, we developed a new fluorescent nanoprobe for rapid, selective and sensitive detection of H2O2. The fluorescent nanoprobe is composed of fluorescein dye (FLS) as a fluorescent probe and MnO2 nanosheets (MnO2 NS) as a quencher. In this study, H2O2 can reduce MnO2 NS in the synthesized composite and release FLS, causing sufficient recovery of fluorescent signal related to the concentration of H2O2. The nanoprobe, with λ ex/λ em at 495/515 nm, has a linear range of 0.04-30 µM, with a limit of detection (LOD) of 7.5 nM and a limit of quantitation (LOQ) of 21 nM. The mean relative standard deviation (RSD) was 2.6% and the applicability of the method was demonstrated by the determination of H2O2 in water and cosmetic samples.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA