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1.
J Pharm Biomed Anal ; 232: 115417, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37120974

RESUMEN

A new approach for testing drug sensitivity to autooxidative degradation in the solid state is demonstrated in this work. A novel solid-state form of stressing agent for autooxidation has been proposed, based on azobisisobutyronitrile loaded into mesoporous silica carrier particles. The new solid-state form of the stressing agent was applied in degradation studies of two active pharmaceutical ingredients: bisoprolol and abiraterone acetate. The effectiveness and predictivity of the method were evaluated by comparing impurity profiles with those obtained by traditional stability testing of commercial tablets containing the investigated APIs. The results obtained by the new solid-state stressor were also compared with those obtained by an existing method for testing peroxide oxidative degradation in the solid state using a complex of polyvinylpyrrolidone with hydrogen peroxide. It was found that the new silica particle-based stressor was able to effectively predict which impurities could be formed by autooxidation in tablets and that this new approach is complementary to methods for testing peroxide oxidative degradation known from the literature.


Asunto(s)
Peróxidos , Dióxido de Silicio , Comprimidos , Estrés Oxidativo
2.
PLoS One ; 16(3): e0248878, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33740023

RESUMEN

Garlic is a well-known example of natural self-defence system consisting of an inactive substrate (alliin) and enzyme (alliinase) which, when combined, produce highly antimicrobial allicin. Increase of alliinase stability and its activity are of paramount importance in various applications relying on its use for in-situ synthesis of allicin or its analogues, e.g., pulmonary drug delivery, treatment of superficial injuries, or urease inhibitors in fertilizers. Here, we discuss the effect of temperature, pH, buffers, salts, and additives, i.e. antioxidants, chelating agents, reducing agents and cosolvents, on the stability and the activity of alliinase extracted from garlic. The effects of the storage temperature and relative humidity on the stability of lyophilized alliinase was demonstrated. A combination of the short half-life, high reactivity and non-specificity to particular proteins are reasons most bacteria cannot deal with allicin's mode of action and develop effective defence mechanism, which could be the key to sustainable drug design addressing serious problems with escalating emergence of multidrug-resistant (MDR) bacterial strains.


Asunto(s)
Liasas de Carbono-Azufre/metabolismo , Fenómenos Químicos , Disulfuros/metabolismo , Ajo/enzimología , Ácidos Sulfínicos/metabolismo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/ultraestructura , Biocatálisis/efectos de los fármacos , Tampones (Química) , Disulfuros/química , Estabilidad de Enzimas/efectos de los fármacos , Liofilización , Concentración de Iones de Hidrógeno , Cinética , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Estereoisomerismo , Ácidos Sulfínicos/química , Temperatura , Factores de Tiempo
3.
Carbohydr Polym ; 252: 117142, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33183601

RESUMEN

The goal of this work was to assess the usability of yeast glucan particles (GPs) as carriers for curcumin and determine the beneficial effect of a pharmacological composite of curcumin in GPs on dextran sulfate sodium induced colitis in rats. The assessment of the anti-inflammatory effect of particular substances was evaluated on the basis of the calculated disease activity index and by assessment of cytokines and enzymes from the gut tissue - tumor necrosis factor α (TNF-α), transforming growth factor ß1, interleukin (IL)-1ß, IL-6, IL-10, IL-17, catalase, superoxide dismutase 2, myeloperoxidase (MPO), and matrix metalloproteinase 9. Composites of GPs with incorporated curcumin showed promising results with the capability to lower symptoms of colitis and significantly decrease the production of pro-inflammatory cytokines TNF-α, IL-1ß, IL-6, and the activity of MPO, as well. The anti-inflammatory effect of the composites was greater than those of pure GPs or curcumin.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/tratamiento farmacológico , Curcumina/uso terapéutico , Portadores de Fármacos/uso terapéutico , Glucanos/uso terapéutico , Animales , Antiinflamatorios/administración & dosificación , Colitis/inducido químicamente , Curcumina/administración & dosificación , Citocinas/metabolismo , Sulfato de Dextran , Glucanos/administración & dosificación , Interleucinas/metabolismo , Masculino , Ratas , Ratas Wistar , Saccharomyces cerevisiae/metabolismo
4.
J Control Release ; 326: 468-481, 2020 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-32721524

RESUMEN

BACKGROUND: Fungi have evolved for 1 billion years and due to their adaptability and resilience can be found in multiple habitats around the globe. Among numerous species of fungi, some are pathogenic, and humans have battled since the dawn of organized agriculture to reduce production losses. With the arrival of fungicides many gains have been made in this struggle. However, though fungicides have greatly contributed to substantial increase in agricultural productivity, their over usage has led to both health and environmental repercussions. They remain cornerstone of the agriculture industry, however, development of safer formulations to champion sustainable and eco-friendly agriculture is of great importance, especially in face of a growing global population, climate change and increasing fungal resistance to existing compounds. SCOPE AND APPROACH: The aim of this review is to present the state of the art in fungicides formulations developed for agrochemistry, also describing recent improvements in their safety, with special focus on fungicides used most against the ten most important fungal pathogens. KEY FINDINGS AND CONCLUSIONS: The major focus in the field remains to be the improvement of the overall performance of the fungicide formulations. The research trends are also moving towards developing more eco-friendly formulations. However, there are still very few studies assessing nanoformulations toxicity and environmental impact. For example, there is still a limited body of research on the holistic assessment of nanoformulation shells' fate in soil and in the environment after release, as well as redistribution within plants after absorption, with no studies on human or environmental exposure.


Asunto(s)
Fungicidas Industriales , Agricultura , Ambiente , Fungicidas Industriales/toxicidad , Humanos , Suelo
5.
Eur J Pharm Biopharm ; 151: 81-90, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32298757

RESUMEN

Abiraterone acetate is a potent drug used for the treatment of metastatic castration resistant prostate cancer. However, currently marketed product containing crystalline abiraterone acetate exhibits strong positive food effect which results in strict dosing regimen. In the present work, a rational approach towards design of novel abiraterone acetate formulations that would allow increased bioavailability on a fasting stomach and thus decreased food effect is presented. Precipitation experiments in biorelevant media were designed to assess pH induced precipitation of the drug and a pool of polymeric excipients was then screened for their potential to inhibit precipitation. The best performing polymeric excipients were subsequently used as carriers for the preparation of amorphous solid dispersions. Two main approaches were followed in order to formulate the drug. The first approach relies on the suppression of precipitation from a supersaturated solution whereas the second one is based on the hypothesis that when the release of the drug is tuned, optimal uptake of the drug can be reached. Optimized formulation prototypes were tested in a rat animal model in an incomplete block, randomized bioequivalence study to assess their relative bioavailability under fasting conditions. We show that both formulation approaches lead to increased bioavailability of abiraterone acetate on a fasting stomach with bioavailability in rats being enhanced up to 250% compared to the original drug product containing crystalline drug.


Asunto(s)
Acetato de Abiraterona/metabolismo , Acetato de Abiraterona/química , Animales , Disponibilidad Biológica , Evaluación Preclínica de Medicamentos , Liberación de Fármacos/fisiología , Excipientes/química , Ayuno/metabolismo , Interacciones Alimento-Droga/fisiología , Concentración de Iones de Hidrógeno , Masculino , Polímeros/química , Ratas , Ratas Wistar , Equivalencia Terapéutica
6.
Colloids Surf B Biointerfaces ; 153: 69-76, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28219840

RESUMEN

The combination of nanoparticles with the polymerase chain reaction (PCR) can have benefits such as easier sample handling or higher sensitivity, but also drawbacks such as loss of colloidal stability or inhibition of the PCR. The present work systematically investigates the interaction of magnetic iron oxide nanoparticles (MIONs) with the PCR in terms of colloidal stability and potential PCR inhibition due to interaction between the PCR components and the nanoparticle surface. Several types of MIONs with and without surface functionalisation by sodium citrate, dextran and 3-aminopropyl-triethoxysilane (APTES) were prepared and characterised by Transmission Electron Microscopy (TEM), dynamic light scattering (DLS) and Fourier Transform Infrared (FT-IR) spectroscopy. Colloidal stability in the presence of the PCR components was investigated both at room temperature and under PCR thermo-cycling. Dextran-stabilized MIONs show the best colloidal stability in the PCR mix at both room and elevated temperatures. Citrate- and APTES-stabilised as well as uncoated MIONs show a comparable PCR inhibition near the concentration 0.1mgml-1 while the inhibition of dextran stabilized MIONs became apparent near 0.5mgml-1. It was demonstrated that the PCR could be effectively carried out even in the presence of elevated concentration of MIONs up to 2mgml-1 by choosing the right coating approach and supplementing the reaction mix by critical components, Taq DNA polymerase and Mg2+ ions.


Asunto(s)
Compuestos Férricos/química , Nanopartículas/química , Reacción en Cadena de la Polimerasa , Citratos/química , Coloides/química , Dextranos/química , Tamaño de la Partícula , Propilaminas/química , Silanos/química , Citrato de Sodio , Propiedades de Superficie , Temperatura
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