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1.
J Pharm Biomed Anal ; 132: 133-140, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27721069

RESUMO

Complex pharmaceuticals are in demand of competent analytical methods able to analyze charge heterogeneity as a critical quality attribute (CQA), in compliance with current regulatory expectations. A notorious example is glatiramer acetate (GA), a complex polypeptide mixture useful for the treatment of relapsing-remitting multiple sclerosis. This pharmaceutical challenges the current state of analytical technology in terms of the capacity to study their constituent species. Thus, a strong cation exchange methodology was designed under the lifecycle approach to support the establishment of GA identity, trough the evaluation of its chromatographic profile, which acts as a charge heterogeneity fingerprint. In this regard, a maximum relative margin of error of 5% for relative retention time and symmetry factor were proposed for the analytical target profile. The methodology met the proposed requirements after precision and specificity tests results, the former comprised of sensitivity and selectivity. Subsequently, method validation was conducted and showed that the method is able to differentiate between intact GA and heterogeneity profiles coming from stressed, fractioned or process-modified samples. In summary, these results provide evidence that the method is adequate to assess charge heterogeneity as a CQA of this complex pharmaceutical.


Assuntos
Cátions , Cromatografia por Troca Iônica/métodos , Acetato de Glatiramer/química , Trifosfato de Adenosina/química , Acetato de Glatiramer/análise , Peptídeos/química , Probabilidade , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Bull Environ Contam Toxicol ; 86(6): 627-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21509467

RESUMO

The presence of endocrine disruptors bisphenol-A, bisphenol-A-dimethacrylate, bisphenol-A-diglycidyl-ether, phthalic-acid, dibutyl-phthalate, diethyl-phthalate and dioctyl-phthalate was determined in vegetable cans, baby bottles and microwaveable containers from the Mexican market. Gas-Chromatography-Mass-Spectrometry was used for the identification and High-Performance-Liquid-Chromatography with UV/Visible light and fluorescence detectors was used for the quantification. Endocrine disruptors were found in all samples. PA and DOP were the substances most commonly found, and maximum concentrations were 9.549 and 0.664 µg/kg, respectively from a jalapeno peppers can. Bisphenol A, phthalic-acid, bisphenol-A-dimethacrylate, bisphenol-A-diglycidyl-ether, dioctyl-phtalate and dibutyl-phthalate were found in baby bottles and microwaveable containers.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Alimentos em Conserva/análise , Fenóis/análise , Ácidos Ftálicos/análise , Plásticos/química , Compostos Benzidrílicos , Alimentação com Mamadeira/instrumentação , Qualidade de Produtos para o Consumidor , Dibutilftalato/análise , Dibutilftalato/química , Dietilexilftalato/análise , Dietilexilftalato/química , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , México , Fenóis/química , Ácidos Ftálicos/química
3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(13-14): 1019-23, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20299292

RESUMO

Interferon-alpha 2b (IFN-alpha 2b) is a recombinant therapeutic cytokine produced as inclusion bodies using a strain of Escherichia coli as expression system. After fermentation and recovery, it is necessary to know the amount of recombinant IFN-alpha 2b, in order to determine the yield and the load for solubilization, and chromatographic protein purification steps. The present work details the validation of a new short run-time and fast sample-preparation method to quantify IFN-alpha 2b in inclusion bodies using Reversed Phase-Ultra Performance Liquid Chromatography (RP-UPLC). The developed method demonstrated an accuracy of 100.28%; the relative standard deviations for method precision, repeatability and inter-day precision tests were found to be 0.57%, 1.54% and 1.83%, respectively. Linearity of the method was assessed in the range of concentrations from 0.05 mg/mL to 0.5 mg/mL, the curve obtained had a determination coefficient (r(2)) of 0.9989. Detection and quantification limits were found to be 0.008 mg/mL and 0.025 mg/mL, respectively. The method also demonstrated robustness for changes in column temperature, and specificity against host proteins and other recombinant protein expressed in the same E. coli strain.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corpos de Inclusão/química , Interferon-alfa/análise , Interferon alfa-2 , Proteínas Recombinantes/análise , Reprodutibilidade dos Testes
4.
Biotechnol Lett ; 29(9): 1369-74, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17479215

RESUMO

Production of periplasmic human interferon-gamma (hINF-gamma) and human interleukin-2 (hIL-2) by the Tat translocation pathway in Escherichia coli BL21-SI was evaluated. The expression was obtained using the pEMR vector which contains the Tat-dependent modified penicillin acylase signal peptide (mSPpac) driven by the T7 promoter. The mSPpac-hINF-gamma was processed and the protein was transported to periplasm. Up to 30.1% of hINF-gamma was found in the periplasmic soluble fraction, whereas only 15% of the mSPpac-hIL-2 was processed, but hIL-2 was not found in the periplasmic soluble fraction.


Assuntos
Escherichia coli/fisiologia , Interferon gama/metabolismo , Interleucina-2/metabolismo , Engenharia de Proteínas/métodos , Humanos , Interferon gama/química , Interferon gama/genética , Interleucina-2/química , Interleucina-2/genética , Periplasma/química , Proteínas Recombinantes/metabolismo , Solubilidade
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