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Integrated Diagnostics of Pharmaceutical Contaminants in Water Supply and Management SystemsEcke, Alexander 31 March 2023 (has links)
Die Kontamination von Trinkwasser mit Arzneimitteln stellt eine ernste Gesundheitsgefahr dar. Um die Trinkwasserqualität kontinuierlich überwachen und im Falle einer Verunreinigung zeitnah reagieren zu können, sind neuartige Sensoren erforderlich. Hier können immunanalytische Methoden, die auf der Bindung des Analyten an hochselektive Antikörper beruhen, hilfreich sein. In dieser Arbeit wurden magnetpartikelbasierte Immunoassays (MBBAs) für zwei relevante Kontaminanten des Trinkwassers entwickelt: Diclofenac (DCF) und Amoxicillin (AMX). Bei letzterem erwiesen sich neben der Ausgangsverbindung auch dessen Hydrolyseprodukte (HPs) als relevant für die Gefährdungsbeurteilung. In einer umfassenden Studie wurde der Einfluss von externen Faktoren und intrinsischen Eigenschaften des Wassers auf die Hydrolysegeschwindigkeit untersucht. Da die Hydrolyse von AMX auch die Erkennung durch den Antikörper beeinflusst, wurde eine Strategie zur Analyse von Proben mit unbekanntem Hydrolysegrad von AMX unter Verwendung des Enzyms β-Lactamase in der Probenvorbereitung entwickelt. Für beide Analyten ermöglichen die MBBAs eine schnelle Quantifizierung mit Ergebnissen in weniger als einer Stunde, was eine wesentliche Verbesserung gegenüber herkömmlichen Immunoassays wie dem Enzyme-linked Immunosorbent Assay (ELISA) darstellt. Im Vergleich zu den entsprechenden ELISAs mit denselben Antikörpern weisen die MBBAs zudem verbesserte analytische Parameter auf, wie einen breiteren Messbereich und niedrigere Nachweisgrenzen. Aufgrund der magnetischen Eigenschaften der Partikel, die als Plattform für die Assays dienen, eignen sie sich für den mobilen und automatisierten Einsatz vor Ort. Ein integriertes Diagnosesystem, bei dem die elektrochemische Detektion mittels Chronoamperometrie auf einem mikrofluidischen Chip eine weitere Miniaturisierung des Systems ermöglicht, wurde entworfen, um die Überwachung der Trinkwasserqualität online in Wasserwerken zu ermöglichen. / The contamination of drinking water with pharmaceuticals represents a severe health risk. In order to monitor the drinking water quality continuously and enable quick countermeasures in case of contamination, novel sensors are required. Here, immunoanalytical methods based on the binding of the analyte to highly selective antibodies can be helpful. In this work, magnetic bead-based immunoassays (MBBAs) have been developed for the detection of two relevant contaminants of drinking water: diclofenac (DCF) and amoxicillin (AMX). In case of the latter, not only the parent drug is of interest in the risk assessment but also its hydrolysis products (HPs). In a comprehensive study, the influence of external factors and intrinsic properties of the water on the rate of hydrolysis was investigated. As the hydrolysis of AMX further impacts the recognition by the antibody, a strategy to analyze samples with unknown hydrolysis degree of AMX was established employing the enzyme β-lactamase in sample preparation. For both analytes, the MBBAs enable the fast quantification with results obtained in less than one hour which represents a major improvement over conventional immunoassays like the enzyme-linked immunosorbent assay (ELISA). Compared to the respective ELISAs with the same antibodies, the MBBAs further exhibit improved analytical parameters such as a broader measurement range and lower limits of detection. Due to the magnetic properties of the beads that serve as a platform for the assays, they are suitable for the mobile and automated detection at the point-of-care. An integrated diagnostic system was designed in which electrochemical detection with chronoamperometry on a microfluidic chip allows for further miniaturization of the system to enable monitoring of the drinking water quality online in water supply pipes at waterworks.
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Formulation, in vitro release and transdermal diffusion of diclofenac salts by implementation of the delivery gap principle / Hanri SmithSmith, Hanri January 2013 (has links)
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation
and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more
effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs,
like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is
known for its many side effects, such as gastric disorders, while fluid and sodium retention are
also commonly observed (Rossiter, 2012:391).
Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral
NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of
topically applied NSAIDs, compared to oral administration and systemic delivery, include the
easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the
avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz &
Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin
Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19;
Prausnitz & Langer, 2008:1261).
An approach that is often applied in optimising the solubility and dissolution rate of poorly water
soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API)
(Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently
administered as a salt, due to the high partition coefficient and very low water solubility of this
molecule (Fini et al., 1999:164).
Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate
the formulation of cosmetic ingredients or solvents into a product that would optimally deliver
active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active
ingredient in the formulation and solubility of the formulation in the skin. This programme could
also be employed to optimise amounts of predetermined ingredients, to propose formulations
that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to
demonstrate transdermal permeation of active ingredients and excipients (JW Solutions
Software, 2013a). When the SDG is known, it mathematically indicates the optimal active
ingredient and topical delivery vehicle to use (JW Solutions, 2013b).
In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2-
hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels:
* An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into
this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%).
Components of the oily phase and its respective amounts, as well as the SDG of formulations
were determined by utilising the FFETM software of JW Solutions (2013a).
The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values
were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery
(Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for
DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291
(DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a
salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention
(Naik et al., 2000:319; Walters, 2007:1312).
Membrane release studies were also carried out in order to determine the rate of API release
from these new formulations. Results confirmed that diclofenac was indeed released from all
nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest
average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion
studies were performed to determine the diclofenac concentration that permeated the skin. The
more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%)
after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h).
The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were
determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated
the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been
optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014
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Formulation, in vitro release and transdermal diffusion of diclofenac salts by implementation of the delivery gap principle / Hanri SmithSmith, Hanri January 2013 (has links)
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation
and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more
effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs,
like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is
known for its many side effects, such as gastric disorders, while fluid and sodium retention are
also commonly observed (Rossiter, 2012:391).
Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral
NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of
topically applied NSAIDs, compared to oral administration and systemic delivery, include the
easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the
avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz &
Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin
Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19;
Prausnitz & Langer, 2008:1261).
An approach that is often applied in optimising the solubility and dissolution rate of poorly water
soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API)
(Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently
administered as a salt, due to the high partition coefficient and very low water solubility of this
molecule (Fini et al., 1999:164).
Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate
the formulation of cosmetic ingredients or solvents into a product that would optimally deliver
active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active
ingredient in the formulation and solubility of the formulation in the skin. This programme could
also be employed to optimise amounts of predetermined ingredients, to propose formulations
that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to
demonstrate transdermal permeation of active ingredients and excipients (JW Solutions
Software, 2013a). When the SDG is known, it mathematically indicates the optimal active
ingredient and topical delivery vehicle to use (JW Solutions, 2013b).
In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2-
hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels:
* An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into
this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%).
Components of the oily phase and its respective amounts, as well as the SDG of formulations
were determined by utilising the FFETM software of JW Solutions (2013a).
The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values
were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery
(Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for
DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291
(DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a
salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention
(Naik et al., 2000:319; Walters, 2007:1312).
Membrane release studies were also carried out in order to determine the rate of API release
from these new formulations. Results confirmed that diclofenac was indeed released from all
nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest
average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion
studies were performed to determine the diclofenac concentration that permeated the skin. The
more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%)
after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h).
The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were
determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated
the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been
optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014
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Příprava a fytoextrakce 125-I značených farmak / Preparation and phytoextraction of 125-I labelled pharmaceuticalsLuptáková, Dominika January 2013 (has links)
Pharmaceuticals are group of organic substances with significant worldwide consumption in human and veterinary medicine. These compounds may be metabolized in the organism, but in some cases they remain unchanged and both are usually excreted via renal excretion in the native form or as metabolites. Large quantities of pharmaceuticals and their metabolites contaminate municipal wastewater. The wastewater treatment plants are unable to remove these substances completely, so they contaminate surface water, groundwater and soil as well. Due to the biological activity of pharmaceuticals, long - term effect may cause bacterial resistance, endocrine influence, DNA and renal damages in non-target organisms. The phytoextraction and the translocation of radiolabeled diclofenac with 125 I were experimentally studied by using of in vitro cultivated plants Helianthus annuus and Zea mays. Efficiency od phytoextraction was monitored as decrease of radioactivity of tested substance [125 I]diclofenac in Murashige-Skoog cultivation medium. Both species are able to extract tested substance during 8 to 10 days of cultivation, with efficiency approximately 85 % using Zea mays and 79 % using Helianthus annuus. Better extraction ability of diclofenac was observed at Helianthus annuus - 80 mg/ kg of dry weight compared...
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Development of a novel rate-modulated fixed dose analgesic combination for the treatment of mild to moderate painHobbs, Kim Melissa 17 September 2010 (has links)
MSc (Med),Dept of Pharmacy and Pharmacology, Faculty of Health Sciences, University of the Witwatersrand / Pain is the net effect of multidimensional mechanisms that engage most parts of the central
nervous system (CNS) and the treatment of pain is one of the key challenges in clinical medicine
(Le Bars et al., 2001; Miranda et al., 2008). Polypharmacy is seen as a barrier to analgesic
treatment compliance, signifying the necessity for the development of fixed dose combinations
(FDCs), which allow the number of tablets administered to be reduced, with no associated loss in
efficacy or increase in the prevalence of side effects (Torres Morera, 2004). FDCs of analgesic
drugs with differing mechanisms of nociceptive modulation offer benefits including synergistic
analgesic effects, where the individual agents act in a greater than additive manner, and a
reduced occurrence of side-effects (Raffa, 2001; Camu, 2002).
This study aimed at producing a novel, rate-modulated, fixed-dose analgesic formulation for the
treatment of mild to moderate pain. The fixed-dose combination (FDC) rationale of paracetamol
(PC), tramadol hydrochloride (TM) and diclofenac potassium (DC) takes advantage of previously
reported analgesic synergy of PC and TM as well as extending the analgesic paradigm with the
addition of the anti-inflammatory component, DC.
The study involved the development of a triple-layered tablet delivery system with the desired
release characteristics of approximately 60% of the PC and TM being made available within 2
hours to provide an initial pain relief effect and then sustained zero-order release of DC over a
period of 24 hours to combat the on-going effects of any underlying inflammatory conditions. The
triple-layered tablet delivery system would thus provide both rapid onset of pain relief as well as
potentially address an underlying inflammatory cause.
The design of a novel triple-layered tablet allowed for the desired release characteristics to be
attained. During initial development work on the polymeric matrix it was discovered that only
when combined with the optimized ratio of the release retarding polymer polyethylene oxide
(PEO) in combination with electrolytic-crosslinking activity, provided by the biopolymer sodium
alginate and zinc gluconate, could the 24 hour zero-order release of DC be attained. It was also
necessary for this polymeric matrix to be bordered on both sides by the cellulosic polymers
containing PC and TM. Thus the application of multi-layered tableting technology in the form of a
triple-layered tablet were capable of attaining the rate-modulated release objectives set out in the
study. The induced barriers provided by the three layers also served to physically separate TM
and DC, reducing the likelihood of the bioavailability-diminishing interaction noted in United
States Patent 6,558,701 and detected in the DSC analysis performed as part of this study.
The designed system provided significant flexibility in modulation of release kinetics for drugs of
varying solubility. The suitability of the designed triple-layered tablet delivery system was
confirmed by a Design of Experiments (DoE) statistical evaluation, which revealed that
Formulation F4 related closest to the desired more immediate release for PC and TM and the
zero-order kinetics for DC. The results were confirmed by comparing Formulation F4 to typical
release kinetic mechanisms described by Noyes-Whitney, Higuchi, Power Law, Pappas-Sahlin
and Hopfenberg. Using f1 and f2 fit factors Formulation F4 compared favourably to each of the
criteria defined for these kinetic models.
The Ultra Performance Liquid Chromatographic (UPLC) assay method developed displayed
superior resolution of the active pharmaceutical ingredient (API) combinations and the linearity
plots produced indicated that the method was sufficiently sensitive to detect the concentrations of
each API over the concentration ranges studied. The method was successfully validated and
hence appropriate to simultaneously detect the three APIs as well as 4-aminophenol, the
degradation product related to PC.
Textural profile analysis in the form of swelling as well as matrix hardness analysis revealed that
an increase in the penetration distance was associated with an increase in hydration time of the
tablet and also an increase in gel layer thickness. The swelling complexities observed in the
delivery system in terms of both the PEO, crosslinking sodium alginate and both cellulose
polymers as well as the actuality of the three layers of the tablet swelling simultaneously suggests
further intricacies involved in the release kinetics of the three drugs from this tablet configuration.
Modified release dosage forms, such as the one developed in this study, have gained widespread
importance in recent years and offer many advantages including flexible release kinetics and
improved therapy and patient compliance.
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Desenvolvimento e validação de um método analítico para determinação dos fármacos Diclofenaco, Nimesulida e Paracetamol em águas superficiais da cidade de São Carlos-SP / Development and validation of analytical method for determining the drug diclofenac, nimesulide and acetaminophen in surface waters from São CarlosVicente, Gustavo Henrique Lourenço 21 October 2011 (has links)
Residuos de fármacos estão presentes em diversas matrizes ambientais e estudos focados na determinação destes tem ganhado grande importância nos últimos anos, devido ao aumento do consumo de medicamentos pela população. A questão do controle de resíduos de compostos farmacologicamente ativos no meio ambiente aquático foi reconhecida como uma das questões emergentes na Química Ambiental, e tem-se dado maior importância visto que os fármacos são encontrados em matrizes em estudos em concentrações de μgL-1 e ngL-1. Nesta pesquisa estudou-se três fármacos antiflamatórios que são amplamente consumidos pela população: diclofenaco, nimesulida e paracetamol. O método analítico foi desenvolvido e validado para a determinação destes fármacos em amostras de águas superficiais da cidade de São Carlos (SP). Inicialmente foi feita a validação do método proposto segundo a Resolução DOQ-CGCRE-008 do INMETRO. Os limites de detecção, e de quantificação e inferior de quantificação do método para a determinação do diclofenaco, nimesulida e paracetamol, foram, respectivamente, 0,5; 1,1 e 1,1 μgL-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média para o diclofenaco foram, respectivamente, R de 0,99, 3,03%, 100,55% e 97,94%. Para a nimesulida, os valores de linearidade, desvio-padrão relativo, exatidão e recuperação, foram, R de 0,98, 2,43%, 101,46% e 100,67%. Já para o paracetamol obteve-se os seguintes valores para linearidade, desvio-padrão relativo, exatidão e recuperação, R de 0,99, 3,50%, 97,94% e 93,17%, respectivamente. Na segunda etapa deste estudo aplicou-se o método validado na análise de amostras de águas coletadas na cidade de São Carlos (SP). Para o método de extração utilizou-se a extração em fase sólida (SPE) e como técnica analítica utilizou-se o HPLC/DAD. Os resultados não indicaram a presença dos fármacos diclofenaco, nimesulida e paracetamol até o limite de detecção do método empregado. / Residues of drugs are present in various environmental matrices and studies focused on the determination of these have gained in importance in recent years, due to increased drug consumption by the population. The issue of control of residues of pharmacologically active compounds in the aquatic environment was recognized as one of the emerging issues in environmental chemistry, and has given greater importance since the drugs are found in studies in matrices at concentrations μgL-1 and ngL-1. In this study was studied three drugs that are widely consumed by the population: diclofenac, nimesulide and acetaminophen. The analytical method was developed for the determination of these drugs in surface water samples from São Carlos (SP). Initially, made a validation of the method proposed second resolution DOQ-008-CGCRE INMETRO. The detection, quantification and lower quantification limits of method for determining of diclofenac, nimesulide and paracetamol were 0.5, 1.1 and 1.1 μgL-1, respectively. The linearity, relative standard , accuracy and average recovery of the method for diclofenac were, respectively, R equal to 0.99, 3.03%, 100.55% and 97.94%. For nimesulide, the values of linearity, relative standard, accuracy and recovery were R equal to 0.98, and 2.43%, 101.46% and 100.67%. For acetaminophen obtained the following values for linearity, relative standard, accuracy and recovery, R equal to 0.99, 3.50%, 97.94% and 93.17% respectively. In the second stage of the study applied the validated method in the analysis of water samples collected in the São Carlos (SP). For extracting the drugs, SPE cartridges were used followed by HPLC / DAD. The results indicate the absense of the studied drugs diclofenac, nimesulide and acetaminophen down to the detection limits of the method employed.
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Estudo comparativo dos efeitos da dexametasona e do diclofenaco sódico sobre o processo reparativo de feridas induzidas no ventre lingual de ratos / Comparative study of the effects of dexamethasone and diclofenac sodium on the repair process of induced wounds in the ventral tongue of ratsArtes, Gisele Ebling 18 September 2012 (has links)
A inflamação é uma resposta protetora para livrar o organismo da causa inicial da lesão celular e suas consequências, porem se excessiva e não modulada, pode provocar a destruição progressiva do tecido. Este estudo pretende contribuir para o esclarecimento da influência de dois anti-inflamatórios, a dexametasona e o diclofenaco sódico, sobre a fase inflamatória do processo reparativo tecidual, bem como sobre o número de mastócitos nas diferentes fases do reparo. Foram utilizadas 60 ratas Wistar, divididas em 3 grupos (1, 2 e 3), medicadas 30 minutos antes de uma intervenção cirúrgica (lesão de 3mm de diâmetro no ventre lingual), com injeção intramuscular de 0,235mg/kg de dexametasona; 4,45mg/kg de diclofenaco sódico ou solução salina estéril, respectivamente. Os 3 grupos foram subdivididos em a, b, c, d, de acordo com o tempo de sacrifício: 6, 24, 48 e 120 horas após a cirurgia. As lesões foram fotografadas logo no momento cirúrgico e no sacrifício e as fotos utilizadas para análise clínica do processo de reparo e morfometria. As línguas foram extirpadas e enviadas para processamento histológico, os cortes foram direcionados para coloração em hematoxilina-eosina e em Azul de Toluidina para evidenciação e contagem do número de mastócitos. As características do processo reparativo foram descritas por meio de avaliação qualitativa dos seguintes componentes: extensão de áreas necróticas; intensidade de edema intersticial; tipo e intensidade do infiltrado inflamatório; graus de reepitelização, tecido de granulação e neovascularização. Os cortes corados em HE também tiveram seus campos digitalizados e analisados morfometricamente, para quantificação da reepitelização, mensurações do tecido de granulação, celularidade e edema. Os resultados da análise histológica semiquantitativa evidenciaram que o diclofenaco e a dexametasona acarretaram menor infiltrado inflamatório em relação ao controle na fase inflamatória do reparo, porém na fase produtiva a dexametasona exibiu menor intensidade de reepitelização e de neovascularização em relação aos demais grupos. Os resultados da análise histomorfométrica mostraram significativamente menor edema no grupo do diclofenaco em 6h (p=0,0041) e em 24h (p=0,0429), bem como menor porcentagem da celularidade em 6 horas no grupo da dexametasona (p<0,0001). O grupo diclofenaco ainda exibiu menor área de lesão em 120h do que os demais grupos (p=0,0060), indicando maior eficiência de reparo. Quanto à quantidade de mastócitos em 24, 48 e 120 horas, o grupo controle exibiu significativamente os maiores valores (p<0,0001). Com base nesses resultados, conclui-se que o grupo da dexametasona apresentou pior desempenho em relação à reparação; que o diclofenaco sódico apresentou um melhor efeito sobre o fechamento da ferida cirúrgica e redução mais intensa do infiltrado inflamatório, e que ambos provocam redução de mastócitos na área lesionada. / Inflammation is a protective response to rid the body of the initial cause of cell damage and its consequences, but when excessive and unmodulated, may cause progressive destruction of tissue. The aim of this study is to clarify the influence of two anti-inflammatory, diclofenac sodium and dexamethasone on the inflammatory phase of tissue repair process, as well as on the number of mast cells in different stages of repair. It was used 60 Wistar rats, divided into 3 groups (1, 2 and 3), medicated 30 minutes before surgery (lesion 3 mm in diameter in the ventral tongue), with intramuscular injection of 0.235 mg / kg dexamethasone, 4, 45mg/Kg of diclofenac sodium or sterile saline, respectively. The 3 groups were subdivided into a, b, c, d, according to the time of sacrifice, 6, 24, 48 and 120 hours after surgery. The lesions were photographed immediately at surgical time and at sacrifice, the photos were used for clinical analysis of the repair process and morphometry. The tongues were excised and sent for histological processing, the slices were directed for staining with hematoxylin-eosin and toluidine blue, for disclosure and count of the number of mast cells. The characteristics of the repair process were described through qualitative evaluation of the following components: extension of necrotic areas; intensity of interstitial edema, type and intensity of inflammatory infiltrate; degrees of reepithelialization, granulation tissue and neovascularization. Slices stained with HE also had their fields scanned and analyzed morphometrically to quantify reepithelialization, measurements of the granulation tissue, cellularity and edema. The results of semiquantitative histological analysis showed that diclofenac and dexamethasone led to lower inflammatory infiltrate compared to control in the inflammatory phase of repair, although in the productive phase dexamethasone showed less intensity of reepithelialization and neovascularization compared to the other groups. The results of the histomorphometric analysis showed significantly less edema in the diclofenac group at 6h (p = 0.0041) and 24 (p = 0.0429), as well as a lower percentage of cellularity in 6 hours in the dexamethasone group (p <0.0001). The diclofenac group also exhibited lower lesion area at 120h than the other groups (p = 0.0060), indicating greater efficiency of repair. Regarding the quantity of mast cells 24, 48 and 120 hours, the control group exhibited significantly higher values (p <0.0001). Based on these results, we conclude that the dexamethasone group showed the worst performance in relation to repair; that diclofenac sodium showed a better effect on surgical wound closure and greater reduction of inflammatory infiltration, and that both cause a reduction of mast cells in the injured area.
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Validação de correlação in vitro-in vivo para comprimidos de liberação modificada de diclofenaco de sódio / Validation of in vivo-in vitro correlation for modified release tablet containing sodium diclofenacMelo, Rafael da Silva 15 March 2012 (has links)
A dissolução de fármacos administrados por via oral é pré-requisito para sua absorção e eficácia clínica. Esta constatação fornece a base para as tentativas de estabelecer correlações entre a dissolução in vitro e a biodisponibilidade in vivo de medicamentos, denominadas correlações in vitro - in vivo (CIVIV). As correlações in vitro-in vivo referem-se ao estabelecimento de uma relação racional entre propriedades biológicas, ou parâmetros derivados destas, produzidas por uma forma farmacêutica, e suas propriedades ou características físico-químicas. O estabelecimento desse tipo de correlação de dados pode possibilitar a substituição dos estudos in vivo, necessários para avaliação da biodisponibilidade de medicamentos, por estudos in vitro, com grandes vantagens éticas e econômicas. A probabilidade de obtenção de correlação in vitro-in vivo é maior quando o processo limitante da absorção do fármaco é a dissolução, o que ocorre para medicamentos contendo fármacos de classe biofarmacêutica II (baixa solubilidade e alta permeabilidade) e para sistemas de liberação controlada de fármacos. O diclofenaco de sódio (DFS) é um fármaco que possui ampla absorção através do intestino (próximo a 100%) e baixa solubilidade em pH abaixo de 6,0, o que o inclui na classe II do SCB. Caracteriza-se como antiinflamatório não esteroidal, com atividades analgésica e antipirética. Considerando as características físico-químicas e farmacológicas do DFS, é objetivo deste trabalho desenvolver e realizar uma validação interna e externa de correlação CIVIV para formulações contendo este fármaco. Para o desenvolvimento e validação interna de CIVIV, foram empregados comprimidos matriciais de DFS contendo o excipiente hidroxipropilmetilcelulose (HPMC) como agente controlador da liberação do fármaco. Três formulações de DFS contendo HPMC em diferentes concentrações (com diferentes taxas de liberação do fármaco) foram avaliadas em estudo de dissolução. Os dados de fração absorvida, obtidas pelo método de deconvolução (MOURÃO, 2009), foram plotados diretamente com os dados de fração dissolvida, obtendo um CIVIV com determinação linear de 0,9738. Para a validação externa, o modelo de CIVIV obtido (intercepto e inclinação) foi utilizado para prever os dados de fração absorvida a partir dos dados de dissolução, empregando três formulações comerciais de DFS. Os resultados de absorção foram extrapolados pelo método de convolução para a obtenção da curva plasmática prevista. Os dados da curva plasmática prevista foram comparados aos dados da curva real de DFS, obtidas no estudo de biodisponibilidade, e os erros de predição (EP%) entre as curvas, foram estabelecidos para a validação externa. Uma CIVIV de nível C foi estabelecida entre diversos parâmetros, empregando as formulações matriciais de DFS e as formulações comerciais. De acordo com os resultados de nível C obtidos, a metodologia de dissolução proposta pode ser empregada para o desenvolvimento de novas formulações contendo o fármaco DFS. / The dissolution of drugs administered orally is a pre-requisite for its absorption and clinical effectiveness. This finding provides the basis for attempts to establish correlations between in vitro dissolution and in vivo bioavailability of drugs, called correlations in vitro-in vivo (IVIVC). The correlation between in vitro-in vivo refers to the establishment of a rational relationship between biological properties, or parameters derived from those produced by a pharmaceutical form and its properties or physicochemical characteristics. The establishment of this type of correlation data may allow the replacement of in vivo studies necessary to evaluate the bioavailability of drugs, for in vitro studies with high ethical and economic advantages. The probability of obtaining correlation in vitro-in vivo is greater when the process of limiting drug absorption is dissolution, which occurs for drug products containing drugs biopharmaceutical class II (low solubility and high permeability) and controlled release systems drugs. Diclofenac sodium (DFS) is a nonsteroidal anti-inflammatory drug with analgesic and antipyretic properties. The objective of this work is to develop and implement an internal and external validation correlation IVIVC for formulations of DFS. For the development and internal validation of IVIVC were employees of DFS matrix tablets containing the excipient hydroxypropyl methylcellulose (HPMC) as a controlling agent drug release. Three formulations containing DFS in HPMC at different concentrations (with different rates of drug release) were evaluated in a study of dissolution. The absorbed fraction data obtained by the deconvolution method (MOURÃO, 2009), were plotted directly with the dissolved fraction data, obtaining a linear IVIVC with determination of 0.9738. For external validation, the obtained IVIVC model (intercept and slope) was used to predict the fraction absorbed data from dissolution data using three commercial formulations of DFS. The absorption results were extrapolated by the method of convolution to obtain the expected plasma curve. The plasma curve data were compared to data provided in real DFS curve, obtained in the bioavailability study, and the prediction error (PE%) between the curves were established for external validation. A level C IVIVC has been established between various parameters, using the matrix formulations of DFS and commercial formulations. According to the results obtained from C-level, the methodology proposed dissolution can be used to develop new drug formulations containing the DFS drug.
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Adsorção de fármacos em carvão ativado : processo em batelada, leito fixo e modelagem das curvas de rupturaFranco, Marcela Andrea Espina de January 2018 (has links)
O presente trabalho estuda a remoção dos fármacos amoxicilina (AMX), diclofenaco sódico (DCF) e paracetamol (PAR) em solução aquosa pelos processos de adsorção em batelada e coluna de leito fixo utilizando o carvão ativado granulado (CAG) como adsorvente. Os experimentos foram realizados para cada fármaco de forma independente. Na adsorção em batelada foram avaliadas as influências do pH (2 – 10), concentração de adsorvente (5 – 20 g L-1) e tempo de contato (5 – 350 min). Foi realizada a investigação da cinética de adsorção e também do equilíbrio de adsorção através de isotermas nas temperaturas de 25, 35 e 45 ºC. A adsorção em leito fixo foi estudada através de planejamentos experimentais, onde foram avaliados os efeitos da concentração inicial do poluente (C0: 20 – 100 mg L-1), massa do leito (W: 0,5 – 1,5 g) e vazão (Q: 3 – 5 mL min-1) sobre o tempo de saturação (tsat) e a quantidade adsorvida (qsat). Os modelos de Thomas, Bohart-Adams e Yan, além de um modelo desenvolvido no software EMSO foram utilizados para análise das curvas de ruptura. O CAG utilizado apresentou área BET de 463 m² g-1 e maior volume de microporos, de 0,20 cm³ g-1. Os experimentos em batelada mostraram que o pH não teve influência significativa sobre a remoção dos três fármacos. O equilíbrio de adsorção da AMX e do DCF foi atingido após 150 min e do PAR após 180 min. O modelo de PSO foi o que melhor representou a cinética de adsorção dos três fármacos. A isoterma de Langmuir descreveu o equilíbrio da AMX a 25 e 35 ºC, e o modelo de Sips a 45 ºC. Já a adsorção do DCF foi representada pela isoterma de Freundlich e o PAR pela de Redlich-Peterson. O estudo termodinâmico indicou que a adsorção dos três fármacos foi espontânea e favorável, além de aumentar com o aumento da temperatura. Na adsorção em leito fixo, foi observado menores valores de tsat com o aumento de C0 e de Q e diminuição de W. Foi verificado que qsat aumentou com o aumento de C0 e diminuição da Q para o planejamento do PAR, onde essa variável foi significativa. Já o aumento de W aumentou qsat no planejamento do PAR e diminuiu nos casos da AMX e DCF. A AMX foi o poluente que apresentou os menores tempos de saturação, seguido do DCF e do PAR, na adsorção em leito fixo. Foi constatado que o modelo de Yan foi o que melhor reproduziu o comportamento das curvas de ruptura para os três fármacos, na comparação com os outros modelos analíticos e com o modelo numérico proposto no software EMSO. De forma geral, foi verificado que os processos de adsorção tanto em batelada quanto em leito fixo apresentam potencial de aplicação como alternativa de tratamento avançado de água e efluentes que contenham fármacos. / The present work studies the removal of amoxicillin (AMX), sodium diclofenac (DCF), and paracetamol (PAR) from water by adsorption onto granular activated carbon in batch process and fixed bed column. Batch adsorption experiments were performed to evaluate the influence of pH (2 – 10), adsorbent concentration (5 – 20 g L-1) and contact time (5 – 350 min). Pseudo-first order, pseudo-second order and intraparticle diffusion models were evaluated in the kinetics investigation. Equilibrium adsorption was investigated using Langmuir, Freundlich, Sips and Redlich-Peterson equations. Fixed bed adsorption was studied through experimental design to evaluate initial contaminant concentration (C0, 20 – 100 mg L-1), amount of adsorbent (W, 0.5 – 1.5 g) and feed flow rate (Q, 3 – 5 mL min-1) effects. The analytical models of Thomas, Bohart-Adams and Yan were selected to investigate the breakthrough curves behavior. In addition, a numerical model was developed and solved using EMSO software. The granular activated carbon (GAC) used had BET surface area of 463 m² g-1 and volume of 0.20 cm³ g-1 of micropores. The pH had no significant effect on the adsorption removal of the three drugs. Adsorption equilibrium of AMX and DCF was reached after 150 min and 180 min for PAR. Pseudo second order model best represented kinetic adsorption of the three compounds. At best conditions in batch process, adsorbent concentration was 12.5 g L-1 for AMX and DCF and 10 g L-1 for PAR. Langmuir isotherm best described AMX adsorption equilibrium at 25 and 35 ºC, and Sips model at 45 ºC. DCF and PAR adsorption followed the Freundlich isotherm and Redlich-Peterson model, respectively. Thermodynamic study indicated that the three drugs adsorption were spontaneous and favorable processes. In addition, adsorption increased at higher temperatures. In fixed bed adsorption experiments, saturation time (tsat) decreased with the increase of initial concentration and flow rate for both drugs. W had positive effect on tsat. The amount adsorbed (qsat) was enhanced at higher C0 and lower Q. qsat was higher at higher Q for AMX and DCF and lower Q for PAR adsorption. Yan model best reproduced breakthrough curves behavior for all drugs among the analytical models and the numerical model developed on EMSO software. Thus, adsorption processes in batch mode and fixed bed column showed to be effective for the removal of drugs of different therapeutic classes from water.
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Efeito da irradiação na toxicidade de fármacos em solução aquosa: cloridrato de fluoxetina, diclofenaco de sódio e mistura de ambos / Radiation effects onto toxicity of pharmaceuticals solution: hydrochloride fluoxetine, sodium diclofenac and their mixtureTominaga, Flavio Kiyoshi 25 August 2016 (has links)
As evidências da contaminação das águas por resíduos de medicamentos e seus subprodutos levou esse grupo de resíduos a compor a lista de poluentes orgânicos emergentes, como consequência da expansão do uso de medicamentos, como o antidepressivo cloridrato de fluoxetina e o anti-inflamatório diclofenaco. Diversos Processos Oxidativos Avançados vêm sendo aplicados para a degradação destes compostos. Dentre eles, o processo de irradiação com feixe elétrons obteve bons resultados na remoção de toxicidade e degradação de fármacos. O presente estudo consistiu em aplicar radiação ionizante como uma possível tecnologia para degradar os fármacos em águas. A irradiação de solução aquosa contendo os fármacos foi aplicada usando acelerador de elétrons, cuja eficiência foi discutida mediante análises químicas (Cromatografia Líquida Ultra Rápida e Carbono Orgânico Total (COT)), ecotoxicológicas (ensaios de toxicidade com Vibrio fischeri e Daphnia similis) e biológicas (Ensaios Respirométricos). Os resultados de COT indicaram mineralização não significativa dos compostos, mesmo sendo observada degradação máxima de 99,9% para o diclofenaco e 55% para o cloridrato de fluoxetina na mistura (1:1) em 5.0 kGy. Foi observada toxicidade aguda dos fármacos, sendo mais acentuada para a fluoxetina, seguido do diclofenaco e, finalmente, da mistura para V. fischeri. Quando D. similis foram empregadas nessa avaliação, a ordem de toxicidade foi de fluoxetina, a mistura de ambos os medicamentos e do diclofenaco. Além disso, foi observada remoção de toxicidade nas amostras irradiadas em todas as doses aplicadas para a bactéria V. fischeri, com maior eficiência de remoção de toxicidade de 55%, em 5 kGy, na mistura dos dois fármacos. Para a D. similis, foi observada remoção significativa de toxicidade da mistura apenas na dose 2,5 kGy. Os ensaios respiroétricos não indicaram biodegradabilidade após o tratamento. / The evidence of water contamination by pharmaceuticals and byproducts residues took them to the list of wastewater emerging organic pollutants, as a result of expansion in drug usage. Fluoxetine hydrochloride antidepressant and diclofenac anti-inflammatory are good examplex. Several Advanced Oxidation Processes have been applied for degradation of these compounds. Among them, the electron beam irradiation process obtained good results in the removal of toxicity and degradation of pharmaceutical. The present study aimed to apply ionizing radiation as a possible technology to degrade the pharmaceutical in water. Irradiation of aqueous solution containing the pharmaceutical was applied using electron accelerator, whose efficiency was discussed through Chemical Analysis, COT, ecotoxicological (Toxicity Testing using Vibrio fischeri and Daphnia similis) and biological measurements (respirometric tests). The COT results indicated not significant mineralization of the compounds. It was observed maximum degradation of 99.9% for diclofenac and 55% for fluoxetine hydrochloride in a mixture solution (1:1) at 5.0 kGy. Regarding ecotoxicity, acute effects were more pronounced for fluoxetine, followed by diclofenac and finally the mixture, to Vibrio fischeri. When Daphnia similis were exposed fluoxetine was more toxic, followed by the mixture of both products and the third was diclofenac. Furthermore, radiation effects for removing toxicity was more effective with V. fischeri bacterium, all applied doses and > 55% removal of toxicity at 5 kGy (in the mixture). To D. similis, toxicity removal was effective when treated with 2.5 kGy ( mixture). No improvements in biodegradability was obtained by radiation ( respirometric tests).
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