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1.
BMC Chem ; 18(1): 164, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252071

RESUMO

Recently, phytochemicals play an important role in cancer management. Curcumin (CUR), a natural phytochemical, has been co-administered with widespread chemotherapeutic agents such as doxorubicin (DOX) due to its excellent antitumor activity and the ability to lower the adverse reactions and drug resistance cells associated with DOX use. The present study aims to determine DOX and CUR utilizing a label-free, selective, sensitive, and precise synchronous spectrofluorimetric method. The obvious overlap between the emission spectra of DOX and CUR prevents simultaneous estimation of both analytes by conventional spectrofluorimetry. To solve such a problem, synchronous spectrofluorimetric measurements were recorded at Δλ = 20 nm, utilizing ethanol as a diluting solvent. Curcumin was recorded at 442.5 nm, whereas DOX was estimated at 571.5 nm, each at the zero-crossing point of the other one. The developed method exhibited linearity over a concentration range of 0.04-0.40 µg/mL for CUR and 0.05-0.50 µg/mL for DOX, respectively. The values of limit of detection (LOD) were 0.009 and 0.012 µg/mL, while the values of limit of quantitation (LOQ) were 0.028 and 0.037 µg/mL for CUR and DOX, respectively. The adopted approach was carefully validated according to the guidelines of ICH Q2R1. The method was utilized to estimate CUR and DOX in laboratory-prepared mixtures and human biological matrices. It showed a high percentage of recoveries with minimal RSD values. Additionally, three different tools were utilized to evaluate the greenness of the proposed approach.

2.
Luminescence ; 38(3): 291-301, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36702460

RESUMO

Novel, selective, facile, and precise spectroscopic approaches were validated to determine nilotinib hydrochloride, a tyrosine kinase inhibitor used to treat patients with chronic myeloid leukemia. These approaches depend on the reaction of the tertiary amine group of nilotinib with erythrosine B in the Britton-Robinson buffer at pH 4. Method I, depends on measuring the absorbance of the formed complex at 551 nm. The absorbance concentration plot showed linearity over the concentration range of 1.0 to 9.0 µg/ml. Method II, involved the measurement of the quenching of the native fluorescence of erythrosine B by adding nilotinib in an acidic medium. The fluorescence quenching of erythrosine B was measured at 549 nm after excitation at 528 nm. This approach showed excellent linearity in the concentration range of 0.04 to 0.7 µg/ml. The limit of detection values for Method I and Method II were 0.225 and 0.008 µg/ml, respectively, while the limit of quantitation values for Method I and Method II were 0.68 and 0.026 µg/ml, respectively. To get the optimal conditions, factors that may affect the formation of the ion-pairing complex were thoroughly examined. The two approaches were carefully validated following the International Conference of Harmonization (ICH Q2R1) guidelines. Statistical assessment of the results achieved using the suggested and previously published comparison approaches showed no significant difference. The approaches were successful in determining nilotinib in a pharmaceutical dosage form as well as spiked human plasma samples. The eco-friendly properties of the methods were evaluated by three different tools.


Assuntos
Eritrosina , Humanos , Pós , Espectrometria de Fluorescência/métodos , Eritrosina/química , Cápsulas
3.
Curr Org Synth ; 17(7): 567-575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32600235

RESUMO

BACKGROUND: 3-Cyanopyridine analogues are significant moieties with a variety of biological effects such as antioxidant, antimicrobial, anti-inflammatory and cytotoxic agents. In addition, they could be applied in the treatment of several diseases. OBJECTIVE: The study conducted cyclo-addition of 3a-e derivatives with malononitrile to yield the corresponding 6-(4-((3-cyano-pyridinyl) amino) phenyl)-4-phenylnicotinonitriles 4a-e. MATERIALS AND METHODS: Physical and spectral analyses were performed to demonstrate the proper structures of all incorporated analogues. The in vitro antimicrobial activity of the preps derivatives was investigated by testing them with a panel of pathogenic strains of bacteria and fungi. The anti-tuberculosis activity was observed against the Mycobacterium tuberculosis H37Rv strain. When examining cytotoxic agents for four different cell lines, researchers found that their activity was persuasive compared with that of standard antibiotics. In addition, the antioxidant activity of the synthesized analogues was evaluated using the DPPH method. RESULTS AND DISCUSSIONS: The synthesized analogues were examined to determine their activity against the M. tuberculosis H37Rv strain. Derivatives 2c, 2e, 3d and 3e had good inhibition. Further screening was done for the highest potency against M. tuberculosis to determine the MICs. The antioxidant efficacy was evaluated via the DPPH technique matched with vitamin C as a positive control. The prospective results showed that the derivatives did not display scavenging efficacies in comparison with the standard. CONCLUSION: Some synthesized derivatives displayed good potency against bacterial activity and M. Tuberculosis. However, the antioxidant performance of these derivatives did not display scavenging efficacies compared to vitamin C. The cytotoxic activity of the synthesized derivatives was examined against various cell lines to display good cytotoxic activity in the order 4a-e > 2a-e > 3a-b.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Nitrilas/farmacologia , Piridinas/farmacologia , Antibacterianos/síntese química , Antineoplásicos/síntese química , Bactérias/efeitos dos fármacos , Reação de Cicloadição , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrilas/síntese química , Piridinas/síntese química , Relação Estrutura-Atividade
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117430, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382228

RESUMO

Five Selective, rapid and sensitive spectrofluorimetric methods were performed in this study for the simultaneous estimation of amlodipine besylate (AML) and atorvastatin (ATR) in their binary mixtures and combination polypills that are used for management of cardiovascular conditions. The first method depends on micelle-enhanced first derivative synchronous fluorimetric analysis (method I) and the other four methods are multivariate analysis techniques based on the use of factor-based calibration prediction methods comprising partial least squares (PLS), Principal Component Regression (PCR), genetic algorithm PLS (GA-PLS) and genetic algorithm PCR (GA-PCR). The synchronous fluorescence spectra of the solutions were measured at a constant wavelength difference; Δλ = 100 nm. The magnitudes of the peaks of the first derivative spectra (1D) were measured at 292 nm and 387 nm for ATR, and AML correspondingly. The multivariate models were constructed utilizing fifteen mixtures as a calibration set and ten mixtures as a validation set. The linearity of all the methods was in the concentration ranges of (0.1-4.0 µg mL-1, 0.4-10.0 µg mL-1) for AML and ATR, correspondingly. Statistical analysis revealed no significant difference between the proposed methods and the reference method. The validity of the proposed methods allows their suitability for quality control work. All the analysis settings were optimized and all the suggested procedures were applied productively for the determination of both drugs in synthetic mixtures, validation set, and combination polypills.


Assuntos
Anlodipino/análise , Atorvastatina/análise , Micelas , Espectrometria de Fluorescência/métodos , Algoritmos , Modelos Lineares , Análise Multivariada , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
R Soc Open Sci ; 6(4): 190310, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31183153

RESUMO

This study is concerned with two sensitive, fast and reproducible approaches; namely, second-derivative synchronous fluorimetry (method I) and reversed phase high-performance liquid chromatography with fluorimetric detection (method II) for synchronized evaluation of losartan (LOS) and amlodipine besylate (AML). Method I is based on measuring second-derivative synchronous fluorescence spectra of LOS and AML at Δλ = 80 nm in water. The experimental factors influencing the synchronous fluorescence of the considered compounds were sensibly adjusted. The chromatographic analysis was executed on a Nucleodur MN-C18 column of dimensions; 250 × 4.6 mm i.d. and 5 µm particle size). The fluorimetric detection was time-programmed at λem = 440 nm for AML (0.0-7.5 min) and at λem = 400 nm for LOS (7.5-10 min) after excitation at λex = 245 nm. The mobile phase is a blend of acetonitrile with 0.02 M phosphate buffer in a proportion of 45 : 55, pH 4.0, pumped using a flow rate of 1 ml min-1. The calibration plots were established to be 0.1-4.0 µg ml-1 for both drugs in method I and 0.05-4.0 µg ml-1 for both drugs in method II. The study was extended to the evaluation of the two drugs in their co-formulated tablets.

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