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1.
J Fluoresc ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625571

RESUMEN

For the first time, clemastine was estimated in this work utilizing two validated resonance Rayleigh scattering (RRS) and fluorimetric methods. The methods relied on forming an association complex in an acidic medium between eosin Y reagent and clemastine. In the spectrofluorimetric approach, the investigated drug was quantified by quenching the fluorescence-emission intensity of eosin Y at 543.5 nm. The RRS method relied on enhancing the RRS spectrum at 331.8 nm, which is produced when eosin Y interacts with clemastine. Suitable conditions were established for the reaction to achieve maximum sensitivity. The linear values obtained from the spectrofluorimetric approach and the RRS method fall into the ranges of 0.2-1.5 µg mL- 1 and 0.25-2.0 µg mL- 1, respectively. It was established that the detection limits for these methods were 0.045 µg mL- 1 and 0.059 µg mL- 1, respectively. The developed methodologies yielded acceptable recoveries when used to estimate the quantity of clemastine in its pharmaceutical tablet dosage form. Regarding the use of greener solvents that were chosen, the suggested and reported methods were compared with the help of the Green Solvents Selecting (GSST) tool for assessing hazardous solvents to achieve sustainability. Furthermore, analytical Eco scale and comprehensive assessments of whiteness, blueness, and greenness were carried out utilizing Modified NEMI, ComplexGAPI, and AGREE evaluation tools. Additionally, recently developed tools such as BAGI and RGB 12 were applied to assess the blueness and the whiteness of the suggested methods.

2.
J Fluoresc ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976089

RESUMEN

The diagnosis of prostate cancer has been evolving in the current decade, with expected mortality rates of 499,000 death by the year 2030. Apalutamide (APL) has been approved in 2018 as the first drug for the controlling of prostate cancer. APL significant success warrantied its high global sales, which are expected to surpass 58% of segment market sales (together with another drug; enzalutamide). Therefore, new, fast and environmentally friendly analytical methods are required for its determination for the quality control and biological monitoring purposes. The proposed research designs and evaluates the first fluorimetric approach based on novel porous green boron-doped carbon quantum dots (B@CDs) for the determination of APL in biopharmaceutical matrices. The synthetic approach has high quantum yield (31.15%). B@CDs were characterized using several tools, including transmission electron microscopy (TEM), dynamic light scattering (DLS), FTIR and Energy dispersive X-ray spectroscopy (EDX) which proved their improved surface properties with an average nano-diameter of 3.0 nm. The interaction between B@CDs and APL led to enhancement their fluorescence at 441 nm (excitation at 372 nm). The approach was validated for the determination of APL within concentration range of 15.0-700.0 ng mL- 1 with quantification limit LOQ 4.37 ng mL- 1 and detection limit LOD 1.44 ng mL- 1. The approach was successfully applied for the determination of APL in human plasma and pharmaceutical monitoring of its marketed tablet form. Then, the approach was assessed for its environmental impact using different metrics and proved its ecological greenness.

3.
Luminescence ; 39(5): e4777, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38785072

RESUMEN

This study introduces a practical and cost-effective method for tracking diltiazem (DLZ) analytically. It utilizes a fluorimetric approach that relies on the modulation of fluorescence intensity of a dye called erythrosine B. Through a one-pot experiment performed in an acidic environment, a complex is rapidly formed between DLZ and erythrosine B. By observing the decrease in erythrosine B emission, a linear calibration plot is established, enabling the detection and quantification of DLZ concentrations ranging from 40 to 850 ng/ml. The estimated limits of detection and quantitation were 10.5 and 32.1 ng/ml, respectively. The variables affecting the DLZ-dye complex system were carefully adjusted. The validity of the approach was confirmed through a thorough evaluation based on the criteria set by ICH guidelines. The accuracy and precision of the methodology were evaluated, and the standard deviation and relative standard deviation were below 2. The strategy was successfully employed to analyze DLZ in tablets and capsules, and no significant variation between the proposed and reported methods as the values of the estimated t-test and F-test at five determinations were below 2.306 and 6.338, respectively. Notably, the method adheres to the principle of green chemistry by utilizing distilled water as the dispersing medium.


Asunto(s)
Diltiazem , Eritrosina , Diltiazem/análisis , Diltiazem/química , Eritrosina/química , Eritrosina/análisis , Espectrometría de Fluorescencia , Comprimidos/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Cápsulas/química , Colorantes Fluorescentes/química , Formas de Dosificación
4.
Luminescence ; 39(5): e4766, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38785095

RESUMEN

In this work, two validated approaches were used for estimating hydroxyzine HCl for the first time using resonance Rayleigh scattering (RRS) and spectrofluorimetric techniques. The suggested approaches relied on forming an association complex between hydroxyzine HCl and 2,4,5,7-tetraiodofluorescein (erythrosin B) reagent in an acidic media. The quenching in the fluorescence intensity of 2,4,5,7-tetraiodofluorescein by hydroxyzine at 551.5 nm (excitation = 527.5 nm) was used for determining the studied drug by the spectrofluorimetric technique. The RRS approach is based on amplifying the RRS spectrum at 348 nm upon the interaction of hydroxyzine HCl with 2,4,5,7-tetraiodofluorescein. The spectrofluorimetric methodology and the RRS methodology produced linear results within ranges of 0.15-1.5 µg ml-1 and 0.1-1.2 µg ml-1, respectively. LOD values for these methods were determined to be 0.047 µg ml-1 and 0.033 µg ml-1, respectively. The content of hydroxyzine HCl in its pharmaceutical tablet was estimated using the developed procedures with acceptable recoveries. Additionally, the application of four greenness and whiteness algorithms shows that they are superior to the previously reported method in terms of sustainability, economics, analytical performance, and practicality.


Asunto(s)
Algoritmos , Hidroxizina , Espectrometría de Fluorescencia , Hidroxizina/análisis , Hidroxizina/química , Antagonistas de los Receptores Histamínicos/análisis , Antagonistas de los Receptores Histamínicos/química , Dispersión de Radiación , Eritrosina/química , Eritrosina/análisis
5.
Luminescence ; 39(4): e4748, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38644515

RESUMEN

In an acidic buffered solution, erythrosine B can react with amiodarone to form an association complex, which not only generates great enhancement in resonance Rayleigh scattering (RRS) spectrum of erythrosine B at 346.5 nm but also results in quenching of fluorescence spectra of erythrosine B at λemission = 550.4 nm/λexcitation = 528.5 nm. In addition, the formed erythrosine B-amiodarone complex produces a new absorbance peak at 555 nm. The spectral characteristics of the RRS, absorbance, and fluorescence spectra, as well as the optimum analytical conditions, were studied and investigated. As a result, new spectroscopic methods were developed to determine amiodarone by utilizing erythrosine B as a probe. Moreover, the ICH guidelines were used to validate the developed RRS, photometric, and fluorimetric methods. The enhancements in the absorbance and the RRS intensity and the decrease in the fluorescence intensity of the used probe were proportional to the concentration of amiodarone in ranges of 2.5-20.0, 0.2-2.5, and 0.25-1.75 µg/mL, respectively. Furthermore, limit of detection values were 0.52 ng/mL for the spectrophotometric method, 0.051 µg/mL for the RRS method, and 0.075 µg/mL for the fluorimetric method. Moreover, with good recoveries, the developed spectroscopic procedures were applied to analyze amiodarone in its commercial tablets.


Asunto(s)
Amiodarona , Eritrosina , Espectrometría de Fluorescencia , Amiodarona/análisis , Amiodarona/química , Eritrosina/química , Eritrosina/análisis , Antiarrítmicos/análisis , Antiarrítmicos/química , Estructura Molecular
6.
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
7.
Luminescence ; 38(4): 477-486, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36880484

RESUMEN

A sensitive and selective phenothiazine-based sensor (PTZ) has been successfully synthesized. The sensor PTZ displayed specific identification of CN- 'turn-off' fluorescence responses with a quick reaction and strong reversibility in an acetonitrile:water (90:10, V/V) solution. The sensor PTZ for detecting CN- exhibits the marked advantages of quenching the fluorescence intensity, fast response time (60 s), and low value of the detection limit. The concentration that is authorized for drinking water by the WHO (1.9 µM) is far higher than the detection limit, which was found to be 9.11 × 10-9 . The sensor displays distinct colorimetric and spectrofluorometric detection for CN- anion due to the addition of CN- anion to the electron-deficient vinyl group of PTZ, which reduces intramolecular charge transfer efficiencies. The 1:2 binding mechanism of PTZ with CN- was validated by fluorescence titration, Job's plot, HRMS, 1 H NMR, FTIR analysis, and density functional theory (DFT) investigations, among other methods. Additionally, the PTZ sensor was successfully used to precisely and accurately detect cyanide anions in actual water samples.


Asunto(s)
Cianuros , Agua Potable , Cianuros/química , Aniones/química , Agua Potable/análisis , Espectrofotometría , Colorimetría/métodos
8.
Luminescence ; 38(2): 92-98, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36427249

RESUMEN

Indigo Carmine is a hazardous dye and produces an allergic action for humans despite the excessive use of the dye in several industrial fields. A sensitive and simple fluorescent assay for determining Indigo Carmine relying on quenching of the fluorescent europium-doped carbon dots by the action of inner filter effect was developed. This sensing platform involved the preparation of europium-doped carbon dots from the hydrothermal carbonization of tannic acid and europium chloride, which was used as fluorescent reagent with a distinctive excitation/emission wavelength at 307/340 nm. Both excitation and emission fluorescence of prepared carbon dots can be successfully quenched by adding Indigo Carmine dye. The developed spectrofluorimetric method exhibits good linearity with the concentration of Indigo Carmine dye in the range of 1.5 to 10.0 µg/ml and provided a limit of detection (LOD) value of 0.40 µg/ml. Furthermore, the prepared carbon nanoparticles were identified and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and ultraviolet (UV)-spectrophotometer techniques. In addition, the developed detecting approach was applied to determine Indigo Carmine in juice samples with acceptable recovery.


Asunto(s)
Carmin de Índigo , Puntos Cuánticos , Humanos , Carbono , Carmín , Europio , Colorantes , Taninos , Colorantes Fluorescentes
9.
Luminescence ; 38(10): 1836-1843, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37555794

RESUMEN

Naftidrofuryl is a vasodilator medication used for treating cerebral and peripheral vascular diseases. In this study, two spectroscopical techniques, spectrofluorimetric and resonance Rayleigh scattering (RRS), were utilized to quantify naftidrofuryl in its pharmaceutical samples. The developed methodologies in this study rely on a facile process of forming an association complex between erythrosine B reagent and naftidrofuryl under acidic conditions. The fluorimetric assay is based on the ability of naftidrofuryl to quench and decrease the native fluorescence intensity of the reagent when measured at λ emis . = 550 nm ( λ excit . = 526 nm). Under similar reaction conditions, the RRS method relies on the observed amplification in the RRS spectrum of the reagent at a wavelength of 577 nm following its interaction with naftidrofuryl. The methods exhibited linearity within the ranges 0.2-1.6 µg/ml (r2  = 0.999) and 0.1-1.4 µg/ml (r2  = 0.9994), with limit of quantitation values of 0.146 and 0.099 µg/ml, and limit of detection values of 0.048 and 0.032 µg/ml, for the fluorometric and the RRS methods, respectively. Moreover, the quenching between the dye and naftidrofuryl was studied using Stern-Volmer analysis, and the methodologies were experimentally optimized and validated. Additionally, acceptable recoveries were achieved when the procedures were applied to determine naftidrofuryl in pharmaceutical samples.


Asunto(s)
Eritrosina , Nafronil , Nafronil/análisis , Espectrometría de Fluorescencia/métodos , Dispersión de Radiación , Preparaciones Farmacéuticas
10.
Luminescence ; 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081623

RESUMEN

In this study, netilmicin (NTM) was selectively assessed in its dosage forms after a facile derivatization reaction. The proposed approach was based on the interaction between NTM and o-phthalaldehyde/2-mercaptoethanol (Roth's reagent). The reaction product was fluorometrically measured at λemission of 434 nm after λexcitation of 338 nm. All reaction conditions for achieving the optimum fluorescence switch-on activity were visualized and monitored. Moreover, the method was validated under ICH guidelines, and was linear over the range 30-210 ng/ml after plotting netilmicin concentrations against the corresponding fluorescence intensity values. In addition, the selectivity of the developed method was investigated against either the co-formulated drug (dexamethasone) or a common ophthalmic drop excipient (benzalkonium chloride) without interference from either of them. Furthermore, the developed method was applied to assay netilmicin in various samples of pharmaceutical eye drops with good recovery. Finally, multicriteria greenness and whiteness metrics were used to evaluate the sustainability, greenness, and whiteness of the approach. The applied tools were the AGREE algorithm, the RGB 12 algorithm, and HEXAGON.

11.
Luminescence ; 37(3): 448-454, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35023289

RESUMEN

In this study, a fluorescence azothiazol-benzenesulfonamide derivative (M-sensor) was prepared for the determination of Mg2+ ions in different samples. The utilized M-sensor exhibited an emission fluorescence activity at 587 nm upon excitation at 537 nm. The developed method was based on the quenching effect of Mg2+ ions on the fluorescence intensity of the M-sensor with the above-mentioned fluorescence features. Furthermore, the utilized M-sensor was complexed with Mg2+ ions in the molar ratio of 1:1 (Mg2+ to M-sensor) and the selectivity of M-sensor toward Mg2+ against other metals ions, and the reversibility and reusability of the sensor were studied and verified. After optimization of the fluorometric detection, the quenching effect was directly proportional to the increase in the concentration of Mg2+ in the linear range 100-600 ng ml-1 with a limit of detection value of 18 ng ml-1 . The fluorescence sensor was successfully applied with good recovery for the determination of Mg2+ in water samples and different pharmaceutical samples (ampoules and suspension) without any interference from aluminium.


Asunto(s)
Magnesio , Agua , Iones , Espectrometría de Fluorescencia/métodos , Sulfonamidas , Bencenosulfonamidas
12.
Luminescence ; 37(6): 1001-1008, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35412020

RESUMEN

Selective fluorometric detection and determination of uranium ions is provided here using a novel fluorescent reagent, namely (E)-4-([4-hydroxynaphthalen-1-yl]diazenyl)-N-(5-methyleisoxazol-3-yl) benzenesulfonamide (UVI reagent). The UVI reagent offers a selective fluorescence enhancement behaviour at emission wavelength = 557 nm. The parameters affecting fluorometric detection of uranium ions, such as the pH, solvent type, ligand concentration, interaction time, and interfering ions, were investigated and adjusted. The proposed UVI reagent can detect and determine uranium ions even at low concentrations, for which the obtained limit of detection was 0.1 ppm. Additionally, this proposed determination protocol was successfully used to detect, monitor, and determine uranium ions in actual water samples.


Asunto(s)
Uranio , Iones , Espectrometría de Fluorescencia , Sulfonamidas , Agua , Bencenosulfonamidas
13.
Luminescence ; 36(6): 1544-1552, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34080773

RESUMEN

In this study, rapid resonance Rayleigh scattering (RRS), spectrophotometric, and spectrofluorimetric methods were performed for facile quantitation of daclatasvir dihydrochloride without interference from sofosbuvir (a co-formulated anti-hepatitis C virus drug). The proposed approaches were based on forming a binary complex between daclatasvir dihydrochloride and merbromin reagent at pH 4.1. The binary complex was measured spectrophotometrically at λmax = 544 nm. The spectrofluorimetric approach relied on the quenching effect of daclatasvir dihydrochloride on the fluorescence strength of merbromin at λEmission = 545 nm. The RRS approach depended on augmentation in the merbromin RRS spectrum at 363 nm upon addition of daclatasvir dihydrochloride. The presented methodologies were linear over the concentration ranges 2.5-15.0, 0.2-1.6 and 0.15-3.0 µg ml-1 with detection limits of 0.45, 0.046, and 0.036 µg ml-1 for the spectrophotometric approach, the spectrofluorometric approach, and RRS approach, respectively. Current approaches were validated in compliance with International Council for Harmonisation guidelines and utilized practically to estimate daclatasvir dihydrochloride either in binary mixtures with sofosbuvir or in its commercial tablet dosage form with good results. Moreover, the test for content uniformity was applied successfully on commercial tablets using the current spectroscopic approaches.


Asunto(s)
Merbromina , Sofosbuvir , Carbamatos , Imidazoles , Pirrolidinas , Espectrometría de Fluorescencia , Comprimidos , Valina/análogos & derivados
14.
Luminescence ; 36(3): 651-657, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33179860

RESUMEN

In this study, spectrofluorimetric and resonance Rayleigh scattering techniques were applied for the first time for determination of rupatadine through two validated methods. The proposed methods were based on a facile association complex formation between rupatadine and erythrosin B reagent in acidic medium. Spectrofluorimetric determination relied on the quenching effect of rupatadine on the fluorescence intensity of erythrosin B at 556 nm (excitation = 530 nm). Conversely, the resonance Rayleigh scattering (RRS) method relied on enhancement in the resonance Rayleigh scattering spectrum of erythrosin B at 344 nm after the addition of rupatadine. The developed methods produced linear results over ranges 0.15-2.0 µg/ml and 0.1-1.5 µg/ml, with detection limits of 0.030 µg/ml and 0.018 µg/ml for the spectrofluorimetric method and the RRS method, respectively. All reaction conditions for rupatadine-erythrosin B formation were optimized experimentally and both methods were validated according to International Council for Harmonisation guidelines. The developed methods were applied to estimate rupatadine content in its pharmaceutical tablet dosage form with acceptable recoveries. Furthermore, a content uniformity test for the commercial rupatadine tablets was successfully applied by the suggested spectroscopic methods according to United States Pharmacopeia guidelines.


Asunto(s)
Eritrosina , Ciproheptadina/análogos & derivados , Indicadores y Reactivos , Dispersión de Radiación , Espectrometría de Fluorescencia , Comprimidos
15.
Luminescence ; 35(7): 1048-1055, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32350964

RESUMEN

A validated thin-layer chromatography (TLC) method combined with fluorescence detection mode was developed for the selective determination of a recently approved anti-hepatitis C virus (HCV) drug (velpatasvir). The separation was performed on silica gel 60 F254 plates using ethylacetate:methanol:triethylamine (48:1.5:1.0, v/v/v) as a mobile phase. Plates were scanned in the fluorescence mode after excitation at 335 nm. This method provided an excellent separation of velpatasvir from sofosbuvir with RF values of 0.22 and 0.46 for velpatasvir and sofosbuvir, respectively, after scanning the developed plates in the ultraviolet detection mode at 335 nm. The calibration curve was linear over the range 4-40 ng/band with a correlation coefficient of 0.9994. The developed procedure was validated according to ICH guidelines with a detection limit of 1.30 ng/band and quantitation limit of 3.95 ng/band. The suggested method could selectively determine velpatasvir with high sensitivity in a synthetic tablet powder containing a co-formulated anti-HCV drug (sofosbuvir) without any interference from excipients or sofosbuvir. In addition, the method was successfully applied for determination of velpatasvir in spiked human plasma with adequate % recovery.


Asunto(s)
Cromatografía en Capa Delgada , Hepacivirus , Hepatitis C , Antivirales , Carbamatos , Compuestos Heterocíclicos de 4 o más Anillos , Humanos , Límite de Detección , Reproducibilidad de los Resultados
16.
Luminescence ; 35(4): 486-492, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31869004

RESUMEN

A fast, low-cost, sensitive, and selective spectrofluorimetric method for the determination of ledipasvir was developed and validated. The method is based on an enhancement in the native fluorescence intensity of ledipasvir by 500% of its original value by the formation of hydrogen bonds between the cited drug and Tween-20 in the micellar system (pH = 5.0). All fluorescence measurements were carried out at 425 nm and 340 nm for emission and excitation wavelengths, respectively. A linear relationship between the concentration of ledipasvir and the observed fluorescence intensity was achieved in the range of 0.1-2.0 µg ml-1 with 0.028, 0.084 µg ml-1 , for detection and quantitation limits, respectively. The acquired selectivity and sensitivity using the proposed method facilitate the analysis of ledipasvir in spiked human plasma with sufficient percentage recovery (95.36-99.30%). The proposed method was developed and validated according to International Council for Harmonisation (ICH) guidelines. Moreover, the cited drug was successfully determined in its pharmaceutical dosage form using the proposed method. In addition, the validity of the proposed results was statistically confirmed using Student's t-test, variance ratio F-test, and interval hypothesis test.


Asunto(s)
Bencimidazoles/sangre , Fluorenos/sangre , Sofosbuvir/química , Composición de Medicamentos , Humanos , Micelas , Estructura Molecular , Sofosbuvir/sangre , Espectrometría de Fluorescencia , Comprimidos/análisis
17.
Luminescence ; 33(7): 1249-1256, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30144265

RESUMEN

Velpatasvir (VLP) is a new, oral, direct-acting antiviral with potent inhibitory activity against all hepatitis C virus (HCV) genotypes. A highly sensitive, simple, fast and specific one fluorometric method for determination of VLP in the presence of sofosbuvir was developed and validated. The fluorescence behavior of VLP in different organic solvents was examined and explained. Methanol was concluded to be the best sensitizing reagent. The native fluorescence intensity of VLP was accomplished at 383 nm with 339 nm for excitation wavelength. The impacts of experimental variables included pH, various organized media, and time of stability were examined and optimized. A linear relationship was achieved between the VLP concentration and the fluorescence intensity in a range of 5 to 5 × 103 ng mL-1 with 0.70 and 0.23 ng mL-1 , for quantitation and detection limits respectively. The proposed method was utilized for analyzing of VLP in human plasma and additionally expanded to examine the stability of VLP after its exposure to various stress conditions, like oxidative, alkaline, acidic, UV, daylight and sunlight conditions, according to ICH guidelines. Furthermore, the kinetics of acidic and oxidative degradations of VLP was examined. Moreover, the half-life times of the reaction (t1/2 ) and the first-order reaction rate constants were estimated. Finally, a suggestion for the degradation pathway was presented.


Asunto(s)
Antivirales/química , Carbamatos/química , Fluorometría/métodos , Compuestos Heterocíclicos de 4 o más Anillos/química , Sofosbuvir/química , Antivirales/sangre , Carbamatos/sangre , Estabilidad de Medicamentos , Fluorescencia , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Hepatitis C/virología , Compuestos Heterocíclicos de 4 o más Anillos/sangre , Humanos , Límite de Detección , Sofosbuvir/sangre
18.
RSC Adv ; 14(24): 16982-16990, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38799220

RESUMEN

In this study, a phenothiazine-thiosemicarbazide (PTZDS) probe was synthesized and characterized. The synthesized PTZDS probe exhibited a yellow color, with a native fluorescence emission at λemission = 550 nm and λexcitation = 450 nm. Over other metal ions, the probe exhibited significant selectivity and sensitivity towards Hg2+ and Cu2+. The probe showed fluorescence quenching along with a minor shift in the absorbance spectra from 400 to 450 nm and 430 nm in the presence of Hg2+ and Cu2+, respectively. In addition, the color of the synthesized probe remarkedly faded with the addition of Hg2+ or Cu2+. Fluorescence measurements, infrared spectroscopy (IR), and density functional theory studies were employed to elucidate the binding process in the PTZDS + Cu2+ and PTZDS + Hg2+ sensor systems. Furthermore, photophysical investigations of the synthesized probe with Hg2+ and Cu2+ were performed. Finally, the probe was successfully employed as a solid-state thin layer chromatography (TLC) optical sensor for detecting Hg2+ and Cu2+ ions.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124596, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38850823

RESUMEN

People frequently administer Tizanidine (TIZ) to treat spasticity resulting from diseases like multiple sclerosis or spinal cord injuries. It also helps prevent muscle spasms. It helps to relax and release tense and stiff muscles by inhibiting specific nerve signals in the brain and spinal cord. The technique employed in this study made use of the unique ability of benzofurazan to confer fluorescent character when reacted with TIZ at specific conditions. This fluorogenic property was harnessed to evolve a remarkably sensitive, affordable, and selective method to quantify TIZ. The resulting yellow fluorescent product was observedat a wavelength beam of 532.9 nm, and an excitation wavelength beam of 474.9 nm was applied. By looking at the response across the TIZ concentration, the calibration chart's linearity was assessed in the range of 40-500 ng/mL. By computation, the approach's detection level (LOD) was determined to be 11.9 ng/mL, while the quantitation level was approximated to be 36 ng/mL. All pertinent factors impacting the strategy's efficacy were thoroughly inspected and adjusted accordingly. The proposed strategy was validated following the guidelines outlined by the ICH. The outcomes confirmed the method's capability for the accurate quantifying of TIZ in tablets, spiked plasma, and pharmaceutical assessing content uniformity.


Asunto(s)
Benzoxazoles , Clonidina , Límite de Detección , Espectrometría de Fluorescencia , Comprimidos , Clonidina/análogos & derivados , Clonidina/análisis , Clonidina/sangre , Espectrometría de Fluorescencia/métodos , Humanos , Benzoxazoles/química , Colorantes Fluorescentes/química , Reproducibilidad de los Resultados , Calibración , Concentración de Iones de Hidrógeno
20.
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
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