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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of an UFLC/MS/MS method for the comparative analysis of oxytocin and artesunate-amodiaquine for validation of field detection systems

Godin, David Andrew 03 November 2016 (has links)
Spurious, falsely-labeled, falsified or counterfeit (SFFC) pharmaceuticals are a health concern that claims hundreds of thousands of lives annually1, a violation of intellectual property rights which cost legitimate companies billions2, and a low-risk high yield revenue stream for organized crime2. While ports of entry and border control points are the primary access control points for SFFC3,4, advances in field portable detection and equipment offers an increasingly effective method for the assessment of pharmaceuticals at regional centers and points of distribution. This is particularly important for less developed countries (LDC) who do not maintain satellite or regional testing facilities. As part of a proposed protocol to assess field portable detection equipment, an ultrafast liquid chromatography, tandem mass spectrometry (UFLC-MS/MS) method for the quantification of liquid formulation Oxytocin was developed. The six minute method was found to have a within run %bias of +/-16%, a linear dynamic range of 150-1000 nanograms/milliliter (ng/ml), and an accuracy within acceptability criteria for all tested concentrations. The effectiveness of three identified transition ions, 723.1, 86.2 and 70.1 Daltons, for the analysis of oxytocin by mass spectrometry was assessed across several figures of merit to include signal to noise ratio, %CV, calibration sensitivity, and analytical sensitivity. The 723.1 ion fragment was recommended for quantification, while the 70.1 dalton ion was recommended as a qualifier ion, although 86.2 also performed within acceptability criteria. A method for the UFLC-MS/MS assessment of degradation products for oxytocin was proposed for specificity testing. Degradation of oxytocin by exposure to highly acidic, basic, and thermal conditions for one hour was attempted. Formation of degraded products was not observed. Additionally, existing High Performance Liquid Chromatography (HPLC) methods for the simultaneous assessment of Artesunate and Amodiaquine HCl were modified to assess compatibility with UFLC. No method assessed produced sufficient quality signal to continue with method development.
2

Isolation and fast analysis of phytochemical constituents in Echinacea species and Rhodiola rosea L. using high-speed counter-current chromatography and ultra fast liquid chromatography-mass spectrometry

Mudge, Elizabeth M Unknown Date
No description available.
3

Otimiza??o e valida??o de m?todos anal?ticos para a determina??o simult?nea de tuberculost?ticos (4-FDC) por CLAE/DAD e CLUE/ DAD

Paiva, Marcelo Vitor de 21 March 2013 (has links)
Made available in DSpace on 2014-12-17T14:16:30Z (GMT). No. of bitstreams: 1 MarceloVPA_DISSERT.pdf: 3152615 bytes, checksum: 2a3513c0df769468fec98423bf2dba29 (MD5) Previous issue date: 2013-03-21 / Tuberculosis is a serious disease, but curable in practically 100% of new cases, since complied the principles of modern chemotherapy. Isoniazid (ISN), Rifampicin (RIF), Pyrazinamide (PYR) and Chloride Ethambutol (ETA) are considered first line drugs in the treatment of tuberculosis, by combining the highest level of efficiency with acceptable degree of toxicity. Concerning USP 33 - NF28 (2010) the chromatography analysis to 3 of 4 drugs (ISN, PYR and RIF) last in average 15 minutes and 10 minutes more to obtain the 4th drug (ETA) using a column and mobile phase mixture different, becoming its industrial application unfavorable. Thus, many studies have being carried out to minimize this problem. An alternative would use the UFLC, which is based with the same principles of HPLC, however it uses stationary phases with particles smaller than 2 ?m. Therefore, this study goals to develop and validate new analytical methods to determine simultaneously the drugs by HPLC/DAD and UFLC/DAD. For this, a analytical screening was carried out, which verified that is necessary a gradient of mobile phase system A (acetate buffer:methanol 94:6 v/v) and B (acetate buffer:acetonitrile 55:45 v/v). Furthermore, to the development and optimization of the method in HPLC and UFLC, with achievement of the values of system suitability into the criteria limits required for both techniques, the validations have began. Standard solutions and tablets test solutions were prepared and injected into HPLC and UFLC, containing 0.008 mg/mL ISN, 0.043 mg/mL PYR, 0.030 mg.mL-1 ETA and 0.016 mg/mL RIF. The validation of analytical methods for HPLC and UFLC was carried out with the determination of specificity/selectivity, analytical curve, linearity, precision, limits of detection and quantification, accuracy and robustness. The methods were adequate for determination of 4 drugs separately without interfered with the others. Precise, due to the fact of the methods demonstrated since with the days variation, besides the repeatability, the values were into the level required by the regular agency. Linear (R> 0,99), once the methods were capable to demonstrate results directly proportional to the concentration of the analyte sample, within of specified range. Accurate, once the methods were capable to present values of variation coefficient and recovery percentage into the required limits (98 to 102%). The methods showed LOD and LOQ very low showing the high sensitivity of the methods for the four drugs. The robustness of the methods were evaluate, facing the temperature and flow changes, where they showed robustness just with the preview conditions established of temperature and flow, abrupt changes may influence with the results of methods / A tuberculose ? uma doen?a grave, por?m cur?vel em praticamente 100% dos casos novos, desde que obedecidos os princ?pios da moderna quimioterapia. S?o considerados f?rmacos de 1? linha no tratamento ? tuberculose: isoniazida, pirazinamida, etambutol e rifampicina. De acordo com USP 33 - NF28 (2010) as an?lises cromatogr?ficas para 3 dos 4 f?rmacos (isoniazida, pirazinamida e rifampicina) duram em m?dia 15 minutos e mais 10 minutos para a obten??o do 4? f?rmaco (etambutol) utilizando outra coluna, com outra mistura de fase m?vel, tornando esta aplica??o na pr?tica industrial desfavor?vel. Uma das alternativas ? utilizar o CLUE, o qual baseia-se nos mesmos princ?pios da CLAE, por?m utiliza fases estacion?rias com part?culas menores que 2 ?m. Dessa forma pretende-se com o presente estudo desenvolver e validar novos m?todos anal?ticos para determina??o simult?nea de tuberculost?ticos por CLAE/DAD e CLUE/DAD. Para isto, foi realizado um screening anal?tico, o qual verificou que ? necess?rio um gradiente de sistema de fase m?vel A (tamp?o acetato:metanol 94:6 v/v) e B (tamp?o acetato:acetonitrila 55:45 v/v). Posteriormente, ao desenvolvimento e otimiza??o do m?todo em CLAE e CLUE com a obten??o dos valores de adequabilidade do sistema dentro dos limites de aceita??es vigente para ambos as t?cnicas, as valida??es deram-se in?cio. Solu??es padr?es e solu??es testes dos comprimidos foram preparadas e injetadas no CLAE e CLUE, contendo isoniazida, pirazinamida, etambutol e rifampicina nas concentra??es de 0,008, 0,043, 0,030 e 0,016 mg.mL-1, respectivamente. A valida??o dos m?todos anal?ticos foram realizadas para: especificidade / seletividade, intervalos da curva anal?tica, linearidade, limite de detec??o, limite de quantifica??o, exatid?o, precis?o (repetibilidade, precis?o intermedi?ria) e robustez. Os m?todos foram adequados para determina??o dos 4 f?rmacos separadamente sem interfer?ncia nos demais. Precisos, devido ao fato de que os m?todos demonstraram que mesmo com varia??o de dias, al?m da repetibilidade, os valores ficaram dentro da faixa preconizada na legisla??o vigente. Lineares (R > 0,99), ou seja, os m?todos foram capazes de demonstrar que os resultados obtidos eram diretamente proporcionais ? concentra??o do analito na amostra, dentro de um intervalo especificado. Exatos, uma vez que os m?todos foram capazes de apresentar valores de coeficiente de varia??o e porcentagem de recupera??o dentro dos limites exigidos (98 a 102%). Os m?todos mostraram LD e LQ com n?veis baixos demonstrando que os m?todos possuem elevada sensibilidade aos quarto f?rmacos. A robustez foi avaliada frente ?s altera??es de temperatura e fluxo, onde os m?todos demonstraram-se robustos apenas nas condi??es previamente estabelecidas de temperatura e fluxo, altera??es bruscas podem acarretar influ?ncia nos resultados dos m?todos

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