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Supercritical fluid chromatography/mass spectrometryPerkins, John Robert January 1989 (has links)
No description available.
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The evaluation of a handheld Raman Analyser for the good laboratory practise (glp) compliant identification of paracetamol raw materials, in a pharmaceutical manufacturing environmentMavumengwana, Bongeka Nomakhephu January 2015 (has links)
The use of a handheld Raman analyser for the positive identification of raw materials in a manufacturing pharmaceutical company was evaluated using paracetamol as test raw material to evaluate whether such a system would meet Aspen’s regulatory requirements. The approach involved subjecting the chosen raw material to identification tests under a variety of conditions so as to evaluate robustness, and specificity of the system. Thus, raw material provided by different suppliers, different packages of one manufacturing batch, and raw materials subjected to different storage conditions were evaluated. Specificity was evaluated by deliberately contaminating a sample of paracetamol with either acetanilide, or 4-aminophenol, or both at varying concentration levels. The results obtained from these investigations showed that the handheld Raman analyser can correctly identify the selected raw material (paracetamol) under a wide range of conditions, but could not correctly identify the presence of the selected contaminants at lower concentration levels (< 10 – 20 mass percent). Finally, a cost-benefit analysis was carried out in which a scenario of an existing FTIR-ATR system is used for the analysis of a specific number of raw material samples per year as opposed to a scenario in which a new handheld Raman analyser has to be purchased, set up, and used for the analysis of the same number of raw material samples. This comparison showed that the handheld Raman analyser had a pay-back time of approximately 6 months and gave a return on investment of approximately the same value as the actual purchase cost.
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"Fleximers" design and synthesis of a new class novel shape-modified nucleosidesZhang, Liang 05 1900 (has links)
No description available.
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Application of sequential injection systems in the assay of pharmaceutical productsTsanwani, Mutshutshu 21 November 2005 (has links)
The concept of sequential injection analysis (SIA), introduced as a simple and convenient principle, has established itself as a well defined analytical technique suitable for routine laboratory analysis. This technique is fully computerized and reliable with a reasonable sample frequency, low sample and reagent consumption and low frequency of maintenance. In pharmaceutical based analysis SIA can be used at each step through the entire production process, from raw material to the final consumer product. With its substantial advantages, an SIA system can replace sophisticated instrumentation facilities, which are unlikely to be used for manufacturing environments. The aim of this study was to investigate the application of the sequential injection analysis technique in the determination of selected substances of biological importance from the pharmaceutical industry (zinc, paracetamol and boron). It is important to control the level of zinc and boron in human, animals and plants. Overdose of paracetamol is a problem in our body. That is why the uniformity tests of paracetamol must be very accurate and precise. The aim was successfully achieved. The results obtained for all substances proved the high reliability of the SIA technique. / Dissertation (MSc (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted
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Validação e cálculo da incerteza de métodos clássicos: titulométricos e espectrofotométricos utilizados na determinação de ácido ascórbicoJerônimo, Marlene [UNESP] 19 March 2012 (has links) (PDF)
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jeronimo_m_dr_arafcf.pdf: 924549 bytes, checksum: deb5b1b247d16a3e3dd39dbb0f5987fb (MD5) / Universidade Estadual Paulista (UNESP) / Os laboratórios de análise de alimentos e fármacos necessitam demonstrar competência técnica para garantia da qualidade dos ensaios que realizam, assegurando a confiabilidade e comparabilidade dos resultados que emitem que subsidiam tomadas de decisões relativas a aspectos econômicos, de saúde pública e defesa do consumidor. O presente trabalho apresenta uma abordagem metrológica de métodos clássicos e instrumental para a determinação do ácido ascórbico (AA). Os parâmetros de validação de todos os métodos de análise abordados neste trabalho e o cálculo da incerteza atenderam as diretrizes da ISO-Guia-IEC-17025 e dos guias EURACHEM. Os métodos clássicos validados foram: N-Bromosuccinamida (NBS), Iodo, Iodato de Potássio e Método do 2,6 diclorofenol-indofenol (DCFI). O método instrumental validado foi o espectrofotométrico, utilizando o reagente 2,6 diclorofenol-indofenol. Os parâmetros avaliados foram: a faixa linear de trabalho, seletividade, linearidade, precisão pela norma da American Society for Testing and Materials (ASTM E 691-99) (sn), precisão por repetição (sr), limite de detecção (LD), limite de quantificação (LQ), robustez (teste de Younden-Steiner) e incerteza genérica. A linearidade avaliada pela análise de resíduo (Y-Yo) mostra que a curva é linear em toda a sua extensão ensaiada em todos os métodos validados e eles foram precisos, robustos e exatos. A importância da validação de métodos analíticos está na obtenção de resultados confiáveis e adequados ao uso pretendido / The laboratory analysis of food and drugs need to demonstrate technical competence for quality assurance tests to perform, ensuring the reliability and comparability of results that give off that support decision making on economic, public health and consumer protection. This paper presents a metrological approach of classical methods and instrument for the determination of ascorbic acid (AA). The validation parameters of all methods of analysis in this paper and the calculation of uncertainty within the guidelines of ISO-IEC-17025-Guide and EURACHEM guides. The classical methods have been validated: N-Bromosuccinamida (NBS), Iodine, Potassium iodate method and 2.6-dichlorophenol indophenol (DCPI). The instrumental method was validated spectrophotometric reagent using 2.6-dichlorophenol indophenol. The parameters evaluated were: the linear range of work, selectivity, linearity, accuracy in the standard American Society for Testing and Materials (ASTM E 691-99) (sn), by repetition accuracy (sr), limit of detection (LD), limit of quantification (LQ), robustness (test-Younden Steiner) and general uncertainty. Linearity was assessed by residual analysis (Y-Yo) shows that the curve is linear over its entire length in all tested methods validated and they were accurate and robust The importance of validation of analytical methods is to obtain reliable results and suitable for intended use
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A study of activation analysis capabilities of the neutron generator with a tritium target in determing the source of certain drugsPresdorf, Ronald L. 03 June 2011 (has links)
This study was an evaluation of the applicability of the neutron generator in identifying the manufacturing sources of drugs by studying; trace elements present in drug samples. The motivation w1as the possible assistance to law enforcement agencies in tracing illicit drugs to their origins.Eight samples of dextroamphetamine sulfate were used in the evaluation process. The samples were activated with a neutron generator producing a 14MMeV neutron flux of the order of 1010 neutrons/sec/cm2. A pair of NaI detectors and a multichannel analyzer were used to study, the decay spectra of the samples.The analytical system was found in most cases to be quite capable of detesting elements which were present in a few parts per million. Little success was encountered in detecting elements present at levels commonly considered to be trace amounts. Phosphorus, silicon, sodium, iron, and strontium where found in amounts ranging from 65 to 250,000 parts per million.Ball State UniversityMuncie, IN 47306
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Crystal form and defect analysis of pharmaceutical materialsEddleston, Mark David January 2012 (has links)
No description available.
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Bioavailability studies on various dosage forms of the anorectic, diethylpropion hydrochloride.Dangor, Cassim Mahomed. 07 October 2013 (has links)
The stereo-chemistry, structure activity relationships and the metabolism
of the anorectic drug, diethylpropion hydrochloride, have been reviewed
briefly, together with the analytical methods for the determination of
this drug and its metabolites in biological fluids. In addition, the
physico-chemical properties, mode of action, pharmacology and uses of the
metabolites have been presented.
A comprehensive review on general principles of salivary excretion of
drugs and their therapeutic drug monitoring in saliva with relevant
published data on saliva/plasma drug concentration relationships has been
outlined.
Sensitive and specific assay procedures, based on gas-liquid
chromatography for the identification, separation and determination of
diethylpropion and its two major metabolites i.e. ethylaminopropiophenone
(11) and diethylnorpseudoephedrine (IV) in aqueous and biological fluids,
have been developed. These methods were used to study the urinary
excreUon as well as saliva and plasma levels of the two major
metabolites and, where possible, the unchanged drug, in man.
Sustained release pellets with diffusion rate-controlled membranes were
employed to control the rate of input into the body by oral or rectal
route of administration. Urinary excretion data and plasma levels of
metabolites 11 and IV in volunteers, where the urine was controlled at an
acidic pH, were used for the evaluation of the bioavailabilities of
different dosage forms of diethylpropion hydrochloride. The
concentrations of metabolites 11 and IV were also measured in saliva and
in plasma after administration of the drug in different doses and dosage
forms: relationships between saliva and plasma concentrations (S/P) and
between urinary excretion rates and plasma concentrations (U/P) were
developed for each of the two metabolites during plateau levels after
oral administration of the sustained release pellets (Lot R 7773). The
potential use of salivary excretion of the metabolites as an index to
monitor their plasma levels and bioavailabilities, was examined.
The distinct advantage of using a subdivided controlled release system
(i. .e. sustained release pellets) to a single unit sustained release
tablet (erosion-core type) in relation to influence of the physical
presence of food on the rate and extent of absorption has been
demons t rated . It was found that the route of administration (oral or
rectal) did not significantly affect the bioavailability of the sustained
release pellets.
The study also involved the investigation of the release of the drug from
the pellets. Because the release control step was diffusion, no
significant influences on dissolution rates were observed with the use of
different dissolution test models and agitation intensities. The
influence of the concentration and composition (presence of cations viz.
Na+ and K+ i~r anions viz . phosphate and borate) of the dissolution
medium on the release of the drug from sustained release pellets, was
also studied. Any potential changes in the dissolution pattern on
storage of the pellets under different conditions (4°C, room temperature
and 37°C) ovrr, a period of at least one year, were investigated.
The in vitro and in vivo correlations of two lots of sustained release
pellets, each exhibiting different dissolution profiles, and administered
rectally and orally, were developed: the in vitro data on the free drug
were related to the sum of the urinary excretion data of metabolites II
and IV.
An attempt to use an empirical approach to predict urinary excretion rate
profiles of metabolite II after oral administration of the sustained
release pellets, was promising; the calculated profiles were reasonably
comparable with those of in vivo studies. However, the complete validity
of such equations needs further investigations. / Thesis (Ph.D.)-University of Durban-Westville, 1984.
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Solid-phase extraction based sample preparation for the determination of drug and organic pollutant residuePule, Bellah Oreeditse 08 February 2011 (has links)
This thesis presents solid phase extraction (SPE) methodologies based on mixed-mode polymeric sorbents; a mixed mode strong anion exchanger (Agilent SampliQ SAX) and a mixed mode strong cation exchanger (Agilent SampliQ SCX). Furthermore, dispersive-SPE based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) method was assessed for applicability in the determination of drug residues. The mixed-mode polymeric sorbents were evaluated for the simultaneous fractionation of drugs that exhibit diverse polarities with acidic, basic and neutral functionalities in biological matrices (plasma and urine). The polymeric skeleton of these sorbents entails an exchanger group and therefore provides two retention mechanisms, strong cation or anion exchange retention mechanisms with hydrophobic interactions. It was demonstrated that with a sequential elution protocol for sample clean-up analytes were fractionated into acidic, basic and neutral classes. The SAX was employed for analysis of ketoprofen, naproxen (acidic drugs), nortriptyline (basic) and secobarbital (neutral) from urine sample. The SCX was used for fractionating phenobarbital, p-toluamide (acidic), amphetamine, m-toluidine (basic) and acetaminophen (neutral drug) from plasma sample. QuEChERS method was employed for quantitative determination of 16 polycyclic aromatic hydrocarbons (PAHs) from fish fillets and soil; 9 sulfonamides (SAs) from chicken muscles and acrylamide (AA) in cooking oil. The analyte recoveries ranged from 79.6 - 109% with RSDs ranging from 0.06 - 1.9% at three different fortification levels. Good linearity (r2 > 0.9990) was attained for most analytes. The limits of detection and quantification ranged from 0.03 - 0.84 μg/ml and 0.81 - 1.89 μg/ml respectively for analytes in biological samples. LODs and LOQs for analytes in food and environmental samples ranged from 0.02 to 0.39 and 0.25 to 1.30 ng/g respectively.
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Development, assessment and optimisation of oral famciclovir formulations for paediatric useMagnus, Laura January 2012 (has links)
Many Active Pharmaceutical Ingredients (API) such as the antiviral agent famciclovir (FCV) are required for paediatric treatment but are not commercially available in age-appropriate dosage forms. It is common practice to prepare oral liquid dosage forms using commercially available tablets, capsules or powdered API and then dispersing or dissolving the crushed and/or powdered materials in a vehicle that the patient can swallow. Vehicles that are commonly used for this purpose include methylcellulose, syrup or combinations of these carriers where possible or commercially available suspending agents such as Ora-Sweet®, if available, can be used. However, several critical factors are overlooked when manufacturing extemporaneous formulations including, but not limited to, physical and chemical properties of the API, excipients, compatibility, stability and bioavailability issues. A stability-indicating High Performance Liquid Chromatography (HPLC) method for the analysis of FCV was developed and validated according to the International Conference on Harmonization (ICH) guidelines. The method is sensitive, selective, precise, accurate and linear over the concentration range 2-120 μg/ml. The stability of 25 mg/ml FCV formulations was assessed in vehicles manufactured from syrup simplex, hydroxypropyl methylcellulose (HPMC), Ora-Sweet® and an aqueous buffer (pH 6) following storage at 25 °C/60% RH and 40 °C/75% RH over six (6) to eight (8) weeks. The shelf life of the products was calculated as the longest period of storage for approximately 90% of the added FCV to be recovered. Formulations were manufactured using syrup simplex or HPMC with methylparaben and propylparaben individually or in combination and with sodium metabisulphite, ascorbic acid or citric acid as antioxidants. The resultant products were subject to quality control analysis for API content, viscosity, pH and appearance and the resultant data were subject to statistical analysis. The degradation rates were calculated for each product and a degradation profile plotted. The degradation rates of FCV in extemporaneous formulations were compared to those of FCV manufactured using a commercially available suspending agent and a buffered vehicle. FCV undergoes major degradation in the presence of sucrose, as observed for formulations in which the vehicle was syrup and Ora-Sweet®. FCV was found to be most stable when dissolved/dispersed in an HPMC vehicle incorporating sodium metabisulphite and a combination of parabens. The formulation that exhibited the maximum stability was manufactured using an aqueous solution buffered to pH 6. Due to the enhanced stability of FCV when added to a buffered vehicle a formulation in which an HPMC vehicle buffered to pH 6 with sodium metabisulphite, methylparaben and propylparaben was selected for optimisation using a Central Composite Design approach (CCD). In this way it was possible to establish a relationship between input variables such as pH, % w/v HPMC, % w/v antioxidant and % w/v preservative and the responses selected for monitoring by means of response surface modelling. A quadratic model was found to be the most appropriate to describe the relationship between input and output variables. Thirty batches of product were randomly manufactured according to the CCD and analysed to establish the stability in respect of viscosity, pH and the amount of FCV remaining following storage and the data were fitted to models using Design-Expert® software. A correlation between input variables and the responses was best described by a quadratic polynomial model. Analysis of Variance indicated that the response surface models were significant (P-value < 0.0001). The pH to which a FCV formulation was buffered was the most significant factor to effect the % drug content and the ultimate pH of the formulation, while the % w/v HPMC had the most significant effect on the viscosity of the product. The optimum composition for the manufacture of an oral liquid FCV formulation was predicted using the optimisation function of the Design-Expert® software. A low % error of prediction was established, indicating that the model is robust and that RSM is an appropriate formulation optimisation tool as it has a high prognostic ability. A liquid FCV formulation was developed, optimised and found to be suitable for its intended purpose. However further optimisation is required in respect of colourants, sweeteners and/or flavourants. The approach followed is useful in ensuring the development of quality products and can be applied in future.
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