Albendazole Solid Dispersions: Influence of Dissolution Medium Composition on In Vitro Drug Release

The rate-limiting step to drug absorption is often dissolution from the dosage form, especially for poorly soluble com-pounds. Two possibilities for improving the dissolution of these drugs are to increase the available surface area and to im-prove their apparent solubilities under physiologically relevant conditions with surfactants as wetting agents. Albendazole (ABZ), one of the most effective broad-spectrum antihelminthic agents, has a very low aqueous solubility, which leads to an erratic availability. Solid dispersions (SD) with different amounts of carriers (P188 and PEG6000) were formulated to improve the ABZ dissolution rate. When the dissolution test is used to infer biopharmaceutical properties of the dosage form, it is es-sential that the method simulates the gastrointestinal conditions. The objective of this study was to examine the applicabil-ity of different dissolution media to the evaluation of ABZ and ABZ-SD dissolution rates. Dissolution profiles were performed by the official method (0.1 N HCl) and Simulated Gastric Fluid modified with a surfactant. Wetting was evaluated through the determination of surface tension and contact angle of the solutions. The dissolution rate of ABZ was clearly affected by the variables assessed in this study. These results have implications in the design of physiologically based dissolution media.Fil: González Vidal, Noelia Luján. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Cátedra de Control de Calidad de Medicamentos; ArgentinaFil: Castro, Silvina Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Sanchez Bruni, Sergio Fabian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatología. Laboratorio de Farmacología; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentin

Recent advances in thermosensitive hydrogels as drug delivery systems: A review

Polymers that exhibit physicochemical responses to stimuli have been widely explored as potential drug delivery systems. Different kind of stimuli investigated to date includes, for example, chemical substances and changes in temperature, pH and electric fields. Polymers that exhibit dramatic changes in their behavior in an aqueous solution at temperatures close to the body temperature are of particular interest in drug delivery and biomedical applications. Thermosensitive polymers have a wide range of applications, specially, the thermosensitive triblock copolymers because they exhibit unique aqueous solution properties, biodegradability and biocompatibility. These copolymers can be designed to be used as potential drug delivery systems for therapeutic protein drugs or poorly water soluble drugs. This article reviews the applications of polymer solutions with the ability to form in situ implants under temperature changes, in areas of interest to biomedical, pharmacist and engineer scientists. Recent advantages on thermosensitive and biodegradable polymers are discussed to give a wide overview of the available strategies to modify them in order to make them suitable for potential applications in health products.Fil: Bermudez, Jose Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Quinteros, Daniela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Grau, Ricardo José Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentin

Antioxidant status in rabbit aqueous humor after instillation of ascorbyl laurate-based nanostructures

The aim of this work was evaluate the antioxidant effect of ascorbyl laurate (ASC12) based nanostructures applied topically to the cornea of ocular normotensive and hypertensive rabbits. The ASC12 was chosen for its capacity to form liquid lyotropic crystal and keeps its free radical trapping power.MethodsThe hypertension model was performed in six rabbits and was obtained by the application of intracameral injections of alpha-chymotrypsin in the right eye. A single 50 mL dose of ascorbyl laurate coagel 2% w/v (COA-ASC12) was applied topically to the cornea of six normotensive and six hypertensive rabbits. The aqueous humor samples were obtained before and after instillation of COA-ASC12 at different times (2 h and 4 h). Antioxidant capacity was determined via the reduction reaction with iron and tripyridyltriazine (FRAP) and the total proteins were measured using the Bradford reagent.ResultsThe kinetic antioxidant capacity in the aqueous humor of normotensive and hypertensive rabbits showed a maxim increment at 4 hours instillation. Also, the antioxidant capacity in the aqueous humor of hypertensive rabbits was ten times lower than in normotensive rabbits. This type of nanostructures has the potential to significantly improve the topical formulation for the prophylaxis and treatment of several eye diseases.Fil: Angel Villegas, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Tartara, Luis Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Caballero, Gabriela. Universidad Nacional de Córdoba; ArgentinaFil: Campana, Vilma. Universidad Nacional de Córdoba; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentin

Ascorbic acid in skin health

Ascorbic acid (vitamin C) is a water-soluble vitamin and a recognized antioxidant drug that is used topically in dermatology to treat and prevent the changes associated with photoaging, as well as for the treatment of hyperpigmentation. Ascorbic acid has neutralizing properties of free radicals, being able to interact with superoxide, hydroxyl and free oxygen ions, preventing the inflammatory processes, carcinogens, and other processes that accelerate photoaging in the skin. Current research focuses on the search for stable compounds of ascorbic acid and new alternatives for administration in the dermis. Unlike plants and most animals, humans do not have the ability to synthesize our own ascorbic acid due to the deficiency of the enzyme L-gulono-gamma-lactone oxidase, which catalyzes the passage terminal in the ascorbic acid biosynthesis. To deal with this situation, humans obtain this vitamin from the diet and/or vitamin supplements, thus preventing the development of diseases and achieving general well-being. Ascorbic acid is involved in important metabolic functions and is vital for the growth and maintenance of healthy bones, teeth, gums, ligaments, and blood vessels. Ascorbic acid is a very unstable vitamin and is easily oxidized in aqueous solutions and cosmetic formulations. Ascorbic acid is extensively used as an ingredient in anti-aging cosmetic products, as sodium ascorbate or ascorbyl palmitate. This review discusses and describes the potential roles for ascorbic acid in skin health and their clinical applications (antioxidative, photoprotective, anti-aging, and anti-pigmentary effects) of topical ascorbic acid on the skin and main mechanisms of action. Considering the instability and difficulty in administering ascorbic acid, we also discuss the importance of several factors involved in the formulation and stabilization of their topical preparations in this review.Fil: Ravetti, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; ArgentinaFil: Clemente, Camila Mara. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Brignone, Sofía Gisella. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hergert, Lisandro Yamil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Villa María. Instituto Académico Pedagógico de Ciencias Básicas y Aplicadas; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentin

Bioadhesive properties of poly(anhydride) nanoparticles coated with different molecular weights chitosan

The aim of this study was to develop and characterize the bioadhesive properties of poly(anhydride) nanoparticles coated with two types of low-molecular weight chitosan (CH20 of 20?kDa or CH50 of 50?kDa) or their thiolated conjugates. Nanoparticles were prepared by a solvent displacement method and characterized by measuring the size, zeta potential, morphology and composition. For bioadhesion studies, nanoparticles were fluorescently labelled with rhodamine B isothiocyanate. In all cases, coated nanoparticles showed a slightly higher size and lower negative zeta potential than uncoated nanoparticles. Nanoparticles coated with CH20 showed a higher adhesive capacity than uncoated nanoparticles. On the contrary, when nanoparticles were coated with CH50, the resulting carriers displayed a decreased ability to develop adhesive interactions within the gut. Finally, the coating of nanoparticles with thiolated chitosan improved their adhesive abilities. Poly(anhydride) nanoparticles coated with thiolated chitosan can be considered as promising bioadhesive particulate carriers for oral delivery strategies.Fil: Llabot, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Hesham, Salman. Universidad de Navarra; EspañaFil: Millotti, Gioconda. Universidad de Innsbruck; AustriaFil: Bernkop Schnürch, Andreas. Universidad de Innsbruck; AustriaFil: Allemandi, Daniel Alberto. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Manuel Irache, Juan. Universidad de Navarra; Españ

COVID-19: Epidemiological Situation of Argentina and its Neighbor Countries after Three Months of Pandemic

Objective: In this work, in order to establish a better comprehension of the association between Argentina and its neighbor countries’ capacity, and COVID-19 burden during the first 3 months, different indicators were evaluated. Method: We analyzed the association between GHSI, INFORM index and COVID-19 burden (number of confirmed cases and deaths), also the number of tests, lethality and the stringency of Governmental policies were evaluated. Results: Uruguay, Paraguay, and Bolivia started earlier different prevention measures. The number of tests differs, as Chile is the 1 that makes more. Uruguay and Paraguay register fewer positive cases and deaths from COVID-19. The GHS index is led by Brazil, followed by Argentina, and then Chile. However, the INFORM index is led by Uruguay followed by Argentina, while Chile and Paraguay are on par. Conclusion: The countries that took preventive measures earlier and carried out a more tests are the ones that are obtaining the best results against COVID-19.publishedVersionFil: Ramírez, María Laura. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Ramírez, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina.Fil: Martinez, Sofia Mickaela. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Martinez, Sofia Mickaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina.Fil: Bessone, Carolina del Valle. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Bessone, Carolina del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina.Fil: Allemandi, Daniel Alberto. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina.Fil: Quinteros, Daniela Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Quinteros, Daniela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina

Albendazole-lipid nanocapsules: Optimization, characterization and chemoprophylactic efficacy in mice infected with Echinococcus granulosus

Cystic echinococcosis (CE), which is caused during the metacestode larval stage of Echinococcus granulosus, is a life-threatening disease and is very difficult to treat. At present, the FDA-approved antihelmintic drugs are mebendazole (MBZ), albendazole (ABZ) and its principal metabolite ABZ sulfoxide (ABZSO), but as these have a therapeutic efficacy over 50%, underlining the need for new drug delivery systems. The aim of this work was the optimization and characterization of previously developed ABZ lipid nanocapsules (ABZ-LNCs) and evaluate their efficacy in mice infected with E. granulosus. LNCs were prepared by the phase inversion technique and characterized in terms of size, surface charge, drug loading, and in vitro stability followed by an in vivo proof-of-concept using a murine model infected with E. granulosus. Stable particle dispersions with a narrow size distribution and high efficiency of encapsulation (≥90%) were obtained. ABZ-LNCs showed a greater chemoprophylactic efficacy than ABZ suspension administered by the oral route as 4 out of the 10 ABZ-LNCs treated mice did not develop any cysts, whereas the infection progressed in all mice from the ABZ suspension group. Regarding the ultrastructural studies of cysts, mice treated with ABZ-LNCs or ABZ suspension revealed changes in the germinal layer. However, the extent of the damage appeared to be greater after ABZ-LNC administration compared to the suspension treatment. These results suggest that ABZ-LNCs could be a promising novel candidate for ABZ delivery to treat CE.Fil: Ullio Gamboa, Gabriela Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Pensel, Patricia Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Elissondo, María Celina. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sanchez Bruni, Sergio Fabian. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Benoit, Jean-Pierre. Micro Et Nanomédecines Biomimétiques; FranciaFil: Palma, Santiago Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentin

Hybrid Formulations of Liposomes and Bioadhesive Polymers Improve the Hypotensive Effect of the Melatonin Analogue 5-MCA-NAT in Rabbit Eyes

For the treatment of chronic ocular diseases such as glaucoma, continuous instillations of eye drops are needed. However, frequent administrations of hypotensive topical formulations can produce adverse ocular surface effects due to the active substance or other components of the formulation, such as preservatives or other excipients. Thus the development of unpreserved formulations that are well tolerated after frequent instillations is an important challenge to improve ophthalmic chronic topical therapies. Furthermore, several components can improve the properties of the formulation in terms of efficacy. In order to achieve the mentioned objectives, we have developed formulations of liposomes (150–200 nm) containing components similar to those in the tear film and loaded with the hypotensive melatonin analog 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT, 100 µM). These formulations were combined with mucoadhesive (sodium hyaluronate or carboxymethylcellulose) or amphiphilic block thermosensitive (poloxamer) polymers to prolong the hypotensive efficacy of the drug. In rabbit eyes, the decrease of intraocular pressure with 5-MCA-NAT-loaded liposomes that were dispersed with 0.2% sodium hyaluronate, 39.1±2.2%, was remarkably higher compared to other liposomes formulated without or with other bioadhesive polymers, and the effect lasted more than 8 hours. According to the results obtained in the present work, these technological strategies could provide an improved modality for delivering therapeutic agents in patients with glaucoma.Fil: Quinteros, Daniela Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vicario de la Torre, Marta. Universidad Complutense de Madrid; EspañaFil: Andrés Guerrero, Vanessa. Universidad Complutense de Madrid; EspañaFil: Palma, Santiago Daniel. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Allemandi, Daniel Alberto. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Herrero Vanrell, Rocío. Universidad Complutense de Madrid; EspañaFil: Molina Martinez, Irene T.. Universidad Complutense de Madrid; Españ

Comparison of two experimental models of glaucoma in rabbits

Objective: to compare two models of experimental glaucoma by induction of ocular hypertension in rabbits.Materials and methods: Sixteen New Zealand female rabbits, 2-3 kg were used. Model A (n=6): cauterization of episcleral and perilimbar veins of the right eye (RE) with surgical electrocautery. Model B (n=10): Injection of ?-chymotrypsin in posterior chamber of RE. Intraocular pressure (IOP) was measured before and after the induction of ocular hypertension (OHT), once a week at the same time of day for 40 days, with a manual tonometer. The animals were euthanized by CO2 inhalation. In both models the control was the IOP of the left eye (LE). The mean and standard error (SE) values of IOP, expressed in mmHg, were compared statistically by applying Student's t-test with a significance level of p&lt;0.05. Results: The IOP in LE (control) of model A: was 12.9±1.05 and in model B: 12.9±1.09. There were no significant differences between the models. Model A: The IOP increase in RE was 14.7% (14.8±1.4) with respect to LE. A significant increase in IOP was observed within the first 24 hours: 23.5±1.9 (p&lt;0.05) compared to the control eye. There were no significant differences with subsequent controls. Model B: The increase in IOP in RE was 129.1% (29.6±3.4) with respect to LE. In all cases an increase was observed from Day 1 (p&lt;0.05). The IOP peak in RE was evidenced on Day 25: 35±3.4 (p&lt;0.05). The increase in IOP induced by model B was significantly higher (p&lt;0.01) than in model A. There was loss of ganglion cells of the retina in both models, but the following anatomo-pathological changes were observed only in model B: buphthalmos, subluxation of the lens and increased excavation of the papilla. Conclusion This study indicates that model B is the most appropriate method to induce a rapid, controlled increase of IOP in rabbits and, more importantly, that this increase may be sustained over extended periods of time. This model could be useful for evaluating the efficacy of new ocular drug delivery systems and for further studies of the physiopathology of glaucoma.</p