Táto práca sa zameriava problematiku interakcie ibuprofénu s pôdnym systémom. Popísané sú jeho základné vlastnosti, správanie a faktory ovplyvňujúce toto správanie. Vo všeobecnosti najvplyvnejšími faktormi je prítomnosť pôdnej organickej hmoty v pôde a pH. Ibuprofén patrí do skupiny nesteroidných protizápalových liečiv. Patrí medzi ľahko dostupné a vysoko konzumované liečivá. Toto prispieva k jeho narastajúcemu transportu a kontaminácii životného prostredia. Jeho prítomnosť v životnom prostredí môže pôsobiť negatívne na živé organizmy. V experimentálnej časti bol preskúmaný vplyv pôdnej organickej hmoty a pH na sorpciu a desorpciu ibuprofénu. Použité boli tri pôdy získané z odlišných regiónov Českej republiky. V rámci procesu sorpcie a desorpcie boli použité koncentrácie v rozmedzí 1 až 10 mg/l. Vplyv pH na sorpciu a desorpciu bol preskúmaný použitím koncentrácie ibuprofénu 10 mg/l a Britton-Robinsonovho pufru s pH 3, 7 a 10. Detekcia ibuprofénu v jednotlivých vzorkách bola uskutočnená pomocou UV-VIS spektrometrie a kvapalinovej chromatografie s hmotnostne spektrometrickou detekciou.

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No / channels that are critical for their development and function. Many ion channels contribute to T cell-mediated autoimmune and/or inflammatory responses, so they are attractive targets for pharmacological immune modulations. In this study, we conduct patch clamp experiments to exam the whole cell currents from lymphocytes after nanoparticles exposure with the aim to test if nanoparticles exposure brings any electrophysiological changes for lymphocytes, and to compare the electrophysiological responses of lymphocytes to drugs in nanoparticles forms. Our result suggests a potential inhibition of effects of IBU N on lymphocytes. Such cytotoxicity of nanoparticles in Lymphocytes may be mainly associated with the early membrane damage. These results are also mirrored by the DNA damages occurred on lymphocytes after exposure of nanoparticles. Further detailed investigation is needed to explain the changes of Lymphocytes in response to NPs in real time and dose differences. This would provide useful information in the evaluation of toxicology of nanoparticles and in understanding the underlying mechanism of their effects on ion channels in health and diseases.

Active Pharmaceutical Ingredients with poor solubility have presented significant difficulties in drug product design and development including slow and ineffective absorption leading to inadequate and variable bioavailability. Therefore it has become increasingly desirable to overcome the low aqueous solubility of drug candidates and develop more novel and innovative formulation approaches to increase the dissolution rate of the poorly soluble drugs. This work focuses on the formulation of novel amorphous ibuprofen-polymer nanoconjugates based on the polymer-drug complexation in order to improve its physical and dissolution characteristics without the use of toxic organic solvents. Plain and ibuprofen-loaded binary and ternary nanoconjugates were prepared using four modified co-precipitation techniques including melt solubilization; alkaline solubilization; surfactant solubilization and hydrotropic complexation techniques. A remarkably high loading capacity was achieved ranging from 89.05 to 99.49% across the four techniques and polymer-polymer ratio of 50:50 was found to be most efficient. All the four techniques reduced the size of ibuprofen (2.87 μm) significantly in the presence of 2.0 x10-3 mM of Diethylaminoethyl Dextran (DEAE-Dextran) in the order melt solubilization (203.25 nm) > alkaline solubilization (185.68 nm) > surfactant (Tween 80) solubilization (122.17 nm) > hydrotropic complexation (77.92 nm). 5.0 x 10-4 mM of chitosan also reduced the size of ibuprofen from 2872.12 to 10.70 nm (268-fold reduction). The FTIR spectroscopic analysis revealed electrostatic, hydrophobic and hydrogen bonding interaction between solubilized ibuprofen and the cationic polymers (DEAE-Dextran and chitosan) to form a new product (an amide). Polymer-polymer complexation also occurred between DEAE-Dextran and gellan as well as chitosan and gellan to a different extent depending on the mixing ratios. 1H and 13C NMR analysis confirmed the conjugation between ibuprofen and each of the cationic polymers as well as the formation of a new amide product. DSC thermal analysis showed that the nanoconjugates exhibited new broad and diffuse peaks confirming that they did exist in amorphous state as multiple complexes. The TGA thermograms of the binary nanoconjugates exhibited one step degradation profile compared with the physical mixture which exhibited two steps. However the ternary nanoconjugates exhibited two steps degradation profile confirming the formation of multiple complexes. Marked enhancement of drug release was achieved by the four techniques compared with the ibuprofen control. All the DG (DEAE-Dextran - Gellan) complexes exhibited a higher release profile than ibuprofen control. Fickian and non-Fickian anomalous mechanisms were deduced for the drug release of ibuprofen from the binary conjugates. The ternary nanoconjugates exhibited non-Fickian (anomalous) diffusion, Fickian diffusion and Super Case II transport release mechanisms. The ternary nanoconjugate hydrogels exhibited complete release (100%) within 48 h. The lowest concentration of DEAE-Dextran, Gellan - Ibuprofen - DEAE-Dextran (GIbDD) 2:0.125, increased the release of ibuprofen by 13.4% however higher concentrations of DEAE-Dextran decreased the release profile steadily. It was concluded that DEAE-Dextran has potentials in the formulation of modified (extended) release of ibuprofen. The most prominent mechanism of release of ibuprofen from the nanoconjugate hydrogel was Super Case II transport. SEM and AFM micrographs of the drug loaded composite pharmaceutical films exhibited concentric spheres with two and three layers for the binary and ternary films respectively. This supports the evidence of internalization of ibuprofen by the polyelectrolyte complex. The FTIR and DSC results confirmed electrostatic and hydrophobic interactions between ibuprofen and DEAE-Dextran as well as between gellan and DEAE-Dextran. Thermal analysis revealed that plain bilayer films were thermally more stable than composite films. The addition of ibuprofen significantly increased (p < 0.05, n = 4) the swelling ratio of the films compared with films without the drug. The drug loaded bilayer films exhibited Fickian diffusion mechanism while the dominating mechanism for composite films was anomalous (Non-Fickian) transport. From the foregoing, it was evident that ibuprofen-polymer nanoconjugate present a novel tool for the delivery of ibuprofen with potential application for transdermal delivery.

Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains vii, 62 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 41-44).

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This report examines differences in risk of myocardial infarction and stroke (cardiovascular events) between the cyclooxygenase-2 (COX-2) inhibitors Rofecoxib, Celecoxib, and Valdecoxib, and the traditional nonsteroidal anti-inflammatory agents (NSAIDs) Naproxen and Ibuprofen, as well as Meloxicam, a preferential COX-2 inhibitor. The population studied was the DoD TRICARE beneficiary population greater than age 40 during the study period. In September of 2004, Rofecoxib was removed from the market due to an increased risk of cardiovascular events. In February of 2005, the Food and Drug Administration (FDA) examined the entire class of COX-2 inhibitors and recommended that Valdecoxib also be withdrawn from the market. According to Department of Defense TRICARE prescription records, COX-2 inhibitor prescription numbers were increasing rapidly and more than $7 million was spent on these agents alone in July of 2004. Logistic regression was used to analyze TRICARE prescription and diagnosis data from calendar years 2002, 2003, and 2004 for cardiovascular event risk comparisons among various NSAIDs. Rofecoxib was found to have a significantly increased risk of cardiovascular events when compared with all other medications in the study, including Valdecoxib. Odds ratios for comparison with Valdecoxib, Celecoxib, Meloxicam, Ibuprofen, and Naproxen were 1.09, 1.14, 1.15, 1.28, and 1.23. Valdecoxib showed a significant increase compared to Ibuprofen, Naproxen, and Celecoxib (odds ratios 1.21, 1.16, and 1.06). Ibuprofen showed a significantly decreased risk relative to all medications except Naproxen. When considering only cardiovascular risk, this study suggests prescribers should consider Ibuprofen or Naproxen as the primary agent of choice, with Meloxicam, and Celecoxib as reasonable second choices. Ultimately, the decision must also weigh the patient's risk of gastrointestinal side effects and cost of therapy.

Desde a década de 90 que estudos relacionados com os polímeros quitina e quitosana têm sido estimulados. A presença em maior quantidade de grupos NH2 na quitosana permite sua aplicação como biomaterial eficiente no carreamento de fármacos e na adsorção de cátions metálicos. Neste trabalho foram preparados filmes e microesferas de quitosana para uso em procedimentos de adsorção de íons prata, liberação de fármaco e atividade antibacteriana. O polímero apresentou grau de desacetilação correspondente a 81% e ponto de carga zero em pH~7. As microesferas obtidas apresentaram um diâmetro médio de 2,911 mm e um desvio padrão de 0,325, quando úmidas. O uso da quitosana na forma de microesferas e filmes proporciona um aumento da área superficial, além de facilitar o manuseio do polímero. Os filmes obtidos foram formados com nanopartículas de prata em etapa única. O melhor pH para o estudo de adsorção de íons Ag+ em meio aquoso está na faixa de pH de 5 a 7, o melhor ajuste foi ao modelo de Langmuir, o tempo ótimo para ocorrer adsorção máxima foi de 10 horas e o valor de energia aparente de adsorção (E) de 6,9 kJ/mol, o que a caracteriza adsorção física. O estudo de liberação de ibuprofeno foi realizado em fluido gástrico simulado e fluido intestinal simulado, a maior liberação do fármaco ocorreu no pH neutro dos fluidos intestinais. A liberação transdérmica de fármaco pelos filmes foi realizada apenas em pH=7,4 para simular o tecido sanguíneo e o ápice da liberação de ibuprofeno ocorreu logo no início do contato do material com o fluido simulado. As microesferas e os filmes com nanopartículas de prata demonstram ter atividade contra E. coli e S. aureus. / Since the 1990s studies related to chitin and chitosan polymers have been stimulated. The presence of more NH2 groups in chitosan allows its application as an efficient biomaterial without drug loading and adsorption of metallic cations. In this work, chitosan films and microspheres were made for use in silver ion adsorption procedures, drug release and antibacterial activity. The polymer showed a degree of deacetylation corresponding to 81% and zero loading point at pH ~ 7. As obtained microspheres had a mean diameter of 2911 mm and a standard deviation of 0.325, when used. The use of chitosan in the form of microspheres and films provides an increase of the surface area, besides facilitating the handling of the polymer. The films were formed with single step silver nanoparticles. The best pH for the Ag+ ion adsorption study in the aqueous medium is in the pH range of 5 to 7, the best fit for the Langmuir model, the optimal time for the maximum adsorption of 10 hours and the apparent energy value of adsorption (E) of 6,9 kJ / mol, which characterizes it physical adsorption. The study of ibuprofen release was performed in simulated gastric fluid and simulated intestinal fluid, further release of the drug occurs no neutral pH of intestinal fluids. Transdermal delivery of drug by films was performed at pH = 7.4 to simulate blood tissue and the apex of ibuprofen release occurred early in contact with the simulated fluid material. As microspheres and films with silver nanoparticles they demonstrate activity against E. coli and S. aureus.