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1.
Sci Rep ; 13(1): 7209, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37137923

RESUMO

Spraying a tertiary blend of the insecticides (hexythiazox, imidacloprid, and thiamethoxam), on tomato fruits, is a routine in agriculture-attentive countries. A simple green sample preparation technique was developed and applied to the field samples. Specific HP-TLC and RP-HPLC methodologies are established to estimate the residual insecticides and applied to the prepared field specimens. In the planner chromatographic methodology, methanol:chloroform:glacial acetic acid:triethyl amine (8.5:1.5:0.2:0.1, v/v) is recommended as a mobile system. The other one is columnar chromatography; acetonitrile: water (20:80, v/v), pH 2.8, is recommended as a mobile system. The validation parameters were examined following the ICH rules. The means percentages and standard deviations of the accuracy of the HP-TLC method for the determined compounds were 99.66 ± 0.974, 99.41 ± 0.950, and 99.89 ± 0.983, correspondingly. The values were 99.24 ± 0.921, 99.69 ± 0.681, and 99.20 ± 0.692, correspondingly, when they were determined by the RP-HPLC method. The relative standard deviation percentages of the methods' repeatability and intermediate precision ranged from 0.389 to 0.920. Both methods were highly specific having resolution factors of ≥ 1.78 and selectivity factors of ≥ 1.71. They were applied to the field samples perfectly.


Assuntos
Inseticidas , Resíduos de Praguicidas , Solanum lycopersicum , Inseticidas/análise , Projetos de Pesquisa , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos
2.
Foods ; 12(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36900526

RESUMO

Applications of analytical quality by design (QbD) approach for developing HPLC (High Performance Liquid Chromatography) methods for food components assays, and separations of complex natural product mixtures, are still limited. The current study developed and validated, for the first time, a stability-indicating HPLC method for simultaneous determinations of curcuminoids in Curcuma longa extracts, tablets, capsules, and curcuminoids' forced degradants under different experimental conditions. Towards separation strategy, critical method parameters (CMPs) were defined as the mobile phase solvents' percent-ratio, the pH of the mobile phase, and the stationary-phase column temperature, while the peaks resolution, retention time, and the number of theoretical plates were recognized as the critical method attributes (CMAs). Factorial experimental designs were used for method development, validation, and robustness evaluation of the procedure. The Monte Carlo simulation evaluated the developing method's operability, and that ensured the concurrent detections of curcuminoids in natural extracts, commercial-grade pharmaceutical dosage-forms, and the forced degradants of the curcuminoids in a single mixture. The optimum separations were accomplished using the mobile phase, consisting of an acetonitrile-phosphate buffer (54:46 v/v, 0.1 mM) with 1.0 mL/min flow rate, 33 °C column temperature, and 385 nm wavelength for UV (Ultra Violet) spectral detections. The method is specific, linear (R2 ≥ 0.999), precise (% RSD < 1.67%), and accurate (% recovery 98.76-99.89%), with LOD (Limit of Detection) and LOQ (Limit of Quantitation) at 0.024 and 0.075 µg/mL for the curcumin, 0.0105 µg/mL and 0.319 µg/mL for demethoxycurcumin, and 0.335 µg/mL and 1.015 µg/mL for the bisdemethoxycurcumin, respectively. The method is compatible, robust, precise, reproducible, and accurately quantifies the composition of the analyte mixture. It exemplifies the use of the QbD approach in acquiring design details for developing an improved analytical detection and quantification method.

3.
J Pharm Sci ; 111(3): 794-809, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34808217

RESUMO

The present work is concerned with tailoring and appraisal of a novel nano-cargo; bilosomes (BLS) dual laded with doxylamine succinate (DAS) and pyridoxine hydrochloride (PDH), the first treatment option against gestational nausea and vomiting, for intranasal delivery. This bifunctional horizon could surmount constraints of orally-commercialized platforms both in dosage regimen and pharmacokinetic profile. For accomplishing this purpose, DAS/PDH-BLS were elaborated integrating phospholipid, sodium cholate and cholesterol applying thin-film hydration method based on Box-Behnken design. Utilizing Design-Expert® software, the effect of formulation variables on BLS physicochemical features alongside the optimal formulation selection were investigated. Then, the optimum DAS/PDH-BLS formulation was incorporated into a thermally-triggered in situ gelling base. The in vivo pharmacokinetic studies were explored in rats for intranasal DAS/PDH-BLS in situ gel compared with analogous intranasal free in situ gel and oral solution. The optimized BLS disclosed vesicle size of 243.23 nm, ζ potential of -31.33 mV, entrapment efficiency of 59.18 and 41.63%, accumulative % release within 8 h of 63.30 and 85.52% and accumulative permeated amount over 24 h of 347.92 and 195.4 µg/cm2 for DAS/PDH, respectively. Following intranasal administration of the inspected BLS in situ gel, pharmacokinetic studies revealed a 1.64- and 2.3-fold increment in the relative bioavailability of DAS and a 1.7- and 3.73-fold increase for PDH compared to the intranasal free in situ gel and oral solution, respectively besides significantly extended mean residence times for both drugs. Thus, the intranasally exploited DAS/PDH-BLS could be deemed as a promising hybrid nanoplatform with fruitful pharmacokinetics and tolerability traits.


Assuntos
Sistemas de Liberação de Medicamentos , Piridoxina , Administração Intranasal , Animais , Disponibilidade Biológica , Doxilamina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Géis , Tamanho da Partícula , Ratos
4.
J Pharm Sci ; 110(8): 3027-3036, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33940026

RESUMO

In the present study, we aimed to formulate, optimize, and characterize azithromycin chitosan coated niosomes (AZM-CTS-NSM) as a novel colloidal system that increases precorneal residence period, eye permeation, and bioavailability. AZM-NSM was formulated via a modified thin-film hydration strategy and then coated with CTS. We assessed the influence of the cholesterol: surfactant molar ratio, CTS concentration, and surfactant type on particle diameter, entrapment, zeta potential, and NSM adhesion force to the corneal mucosal membrane and employed a central composite design (CCD). The resulting optimized AZM-CTS-NSM has a mean diameter of 376 nm, entrapment of 74.2%, surface charge of 32.1 mV, and mucoadhesion force of 3114 dyne/cm2. The optimized AZM-CTS-NSM demonstrated a prolonged in vitro release behavior. When compared with commercial eye drops, the optimized AZM-CTS-NSM produced a 2.61-fold increase in the apparent permeability coefficient, significantly improving corneal permeability. Additionally, ocular irritation was assessed, with no major irritant effects found to be induced by the formulated NSM. Compared with AZM commercial drops, the optimized AZM-CTS-NSM revealed ˃ 3-fold increase in AZM concentration in the rabbit eyes. Collectively, these findings indicate that CTS-NSM is a potentially valuable ocular nanocarrier that could augment the efficacy of AZM.


Assuntos
Quitosana , Conjuntivite Bacteriana , Animais , Azitromicina , Conjuntivite Bacteriana/tratamento farmacológico , Córnea , Sistemas de Liberação de Medicamentos , Lipossomos , Tamanho da Partícula , Coelhos
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 238: 118444, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32413719

RESUMO

This study involves spectroscopic analysis of pesticide residues extracted from tomato, one of the most freshly eaten fruit all over the world. In Egypt, tomato can be protected against pests infection by concomitantly spraying three pesticides namely, acetamiprid (AC), flutolanil (FL) and etofenprox (ET). The three pesticides have been simply and efficiently extracted from the fruits and analyzed by applying the following methods: Differential dual wavelength method, where AC, FL and ET were determined by amplitudes subtraction at 264.8-277 nm, 229-241 nm and 225.6 and 243 nm, respectively after obtaining their first derivative spectra. Modified ratio difference method, where the difference in amplitude values at 261.2 and 241 nm, 273.4 and 236.8 nm and 269.8 and 232 nm was used for determination of AC, FL and ET, respectively. The third method includes recording the amplitudes at 284, 293 and 224 nm for AC, FL and ET, respectively, after mean centering of their spectra. The linear ranges were 1-11, 0.2-2.5 and 0.2-2.5 µg mL-1 for AC, FL and ET, respectively. The methods were proven to be green regarding the Eco-Scale calculations. The methods were efficiently applied for determination of AC, FL and ET in their commercial forms and field trials, where the residues were approximately equal to or below their specified maximum residue limits.


Assuntos
Anilidas/análise , Neonicotinoides/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Solanum lycopersicum/química , Frutas/química , Espectrofotometria Ultravioleta/métodos
6.
Food Chem ; 306: 125640, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606625

RESUMO

Combination of pesticides; acetamiprid, flutolanil and etofenprox are usually used for tomato fruits for protecting them against pest infection. Generally, pesticides, residues could be one of the health hazard sources. Two specific simple sensitive chromatographic methods are developed for simultaneous estimation of the concerning pesticides' residues using simple economic steps of field sample preparation. The first method is HP- TLC method. Hexane: methanol: acetone: glacial acetic acid (8:2:0.5:0.1, by volume) is proposed as a developing system. The second one is RP- HPLC. Acetonitrile: water (75:25, v/v) is proposed as a mobile phase. The recommended methods are completely validated regarding ICH guidelines. Their means percentages and standard deviations of accuracy range 100.32 ±â€¯0.89 to 99.27 ±â€¯0.9. The methods' repeatability and intermediate precision relative standard deviation percentages range 0.395-0.894. They are successfully applied for estimating the pesticides in pure and commercial forms and field samples.


Assuntos
Manipulação de Alimentos , Resíduos de Praguicidas/análise , Piretrinas/análise , Solanum lycopersicum/química , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Segurança
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