Application of the SeDeM system for the preparation of antiparasitic tablets from mesquite flour for use in sheep.

The use of herbal medicine to treat various diseases is becoming increasingly important as an alternative therapy. Numerous plants have been traditionally used for different purposes, including antiparasitic in humans and animals. Diseases caused by gastrointestinal parasites in ruminants, especially by the nematode Haemonchus contortus, cause large economic losses to the producers, whether by complications of the diseases or the cost of treatment. The main way of handling nematodiasis is by administering anthelmintic drugs, but their excessive use has the disadvantage of causing drug resistance; therefore, an alternative is the use of herbal medicine for this purpose. Mesquite (Prosopis spp.) has been used in Mexico to treat gastrointestinal diseases attributed to helminths. The present study aimed to characterize the rheological properties of mesquite flour using the SeDeM Expert System to determine its suitability for tablet production by direct compression. Direct compression technology facilitates the tableting process by reducing manufacturing costs. The results of the present study indicate that mesquite flour can be processed by direct compression. The latter could allow the manufacturing of economic tablets to treat infections by H. contortus in ruminants.

Diseño de estudios Gauge R&R cruzado y anidado para la validación de los modelos matemáticos de Heckel y Ryshkewitch-Duckworth / Design of crossed and nested Gauge R&R studies for the validation of the Heckel and Ryshkewitch-Duckworth mathematical models

INTRODUCCIÓN: Los estudios gauge permiten ganar información sobre el desempeño de procesos y son de utilidad para control de calidad, así como identificación de fuentes de variación. El objetivo del presente estudio, fue diseñar y analizar sistemas de medición para los modelos de Heckel y Ryshkewitch-Duckworth para caracterizar materiales, a través de estudios Gauge R&R. MÉTODO: Estudio Gauge R&R cruzado para evaluar el sistema de medición del peso y estudio Gauge R&R anidado para el sistema de la resistencia a la fractura. RESULTADOS: Ambos estudios cumplieron con los supuestos de normalidad, varianza constante e independencia de los datos, por lo que fue posible determinar la significación de las fuentes de variación (factores) mediante un ANOVA así como su porcentaje de contribución. Para el estudio Gauge R&R cruzado los punzones evaluados contribuyen a la variación de la medición de manera significativa y en un 97,38% de la variación total; los operadores contribuyen en menos del 1% y de manera no significativa y no existió interacción parte-operador. Respecto al estudio Gauge R&R anidado, se identificó que el operador no influyó de manera significativa en la variabilidad de la medición y que ésta es atribuible en un 95% a las diferencias existentes entre las tabletas evaluadas. CONCLUSIONES: Se realizó el diseño, ejecución y análisis de los sistemas de medición, destacando que en ambos estudios la principal fuente de variación fueron las partes evaluadas y que los operadores no contribuyen en la variabilidad de las mediciones, por lo que los estudios pueden usarse para evaluar los modelos matemáticos y durante el control estadístico de un proceso

INTRODUCTION: Gauge studies allow gaining information about the performance of processes and are very useful tools for quality control and identification of variability sources. The objective of the present study was design and analyzes measurement systems for the Heckel and Ryshkewitch-Duckworth models for characterizing materials, through Gauge R&R studies. METHOD: Crossed Gauge R&R study for the evaluation of weight measurement system and nested Gauge R&R study for the system of tablet hardness. RESULTS: Both studies fulfilled with the assumptions of normality, constant variance and data independence, therefore it was possible to estimate the significance of variation sources (factors) through ANOVA and their contribution percentage. The crossed Gauge R&R study showed that the flat punches contributed to variability of the measurement in a significant manner in 97.38% of the total variation of the study; operators did it in less than 1% and they were not statistically significant and there was no Part-Operator interaction. With respect to the nested Gauge R&R study, it was found that the operator did not influence in a statistically significant way in the variability of the measurement and it was attributable in 95% to the existing differences between the tablets evaluated. CONCLUSIONS: Design, run and analysis of the measurement systems was performed, we remark that in both of the studies the main source of variability were the parts evaluated and that operators did not contribute to variability in the measurements; therefore, both studies could be used to evaluate the Heckel and Ryshkewitch-Duckworth mathematical models and also for statistical process control

Comparison of the performance of two grades of metformin hydrochloride elaboration by means of the SeDeM system, compressibility, compactability, and process capability indices.

Quality by design, applied to the development of a pharmaceutical drug, demands scientific methodologies, representing a source of information that will allow for a complete understanding the production process and the materials used for its manufacturing. Although the SeDeM system is a tool that enables a rational development of a product, result does not assure that an assessed material or mixture will be successful in terms of compression, hence, further research will be necessary on these features. The objective of this study was to assess and compare two grades of metformin hydrochloride elaboration: crystalline and direct compression using PXRD, the SeDeM expert system, the Heckel and Ryshkewitch-Duckworth models, as well as process control tools such as control charts and process capability indices to characterize and predict the performance of the materials in a direct compression process. The assessment identified that in spite of dealing with two different technical grades of a material with specific critical quality attributes for each one, PXRD analysis showed we dealt with the same crystalline structure, while the SeDeM system profiles obtained have very close values, and the main differences in materials were observed when subjecting them to conditions that simulate a compaction process with the Ryshkewitch-Duckworth model, in which a 46-times higher mechanical resistance was observed in the direct compression material compared with the crystalline one. The statistical control analysis revealed that only the direct compression material could be used to elaborate tablets whose weight variation was always maintained within the specification and control limits.

Synthesis and drug loading improvements on mesoporous SBA-15 by spray drying.

SBA-15 mesoporous silica is a material used as drug carrier material due to its structural characteristics and biocompatibility. The large surface area of this material improves drug loading and drug release. Typically, SBA-15 is produced by a cooperative self-assembly process under acidic conditions using the triblock copolymers as template and tetraethoxysilane (TEOS) as the silica sources under conventional and batched process. In the last years, spray drying has been proposed to reduce the time to obtain SBA-15 (dry and not calcined) to just seconds, whereas with conventional techniques, this process can take from 6 to 48 h. Additionally, the loading, dissolution, and stability of drugs are improved using co-spray drying (SBA-15 and drugs) due to the pore spatial confinement and avoiding the re-crystallization process of drugs. Furthermore, drug-loaded SBA-15 particles obtained by spray drying have a defined size, high sphericity, and easy handling these characteristics are relevant to its incorporation in dosage forms. Several factors influence the final characteristics of SBA-15 drug-loaded particles, for mention a few: precursors, solvents, time of aging, the temperature of drying, pressure, etc. In this review, the key parameters for the synthesis and loading of drugs on SBA-15 using the spray drying technique are explored and analyzed giving information about how these parameters impact the loading, dissolution, and stability of drugs.

Feasibility of obtaining in situ nanocapsules through modified self-microemulsifying drug delivery systems. A new manufacturing approach for oral route administration.

Nanocapsules (NCs) are submicron-sized core shell systems which present important advantages such as improvement of drug efficacy and bioavailability, prevention of drug degradation, and provision of controlled-release delivery. The available methods for NC production require expensive recovery and purification steps which compromised the morphology of NCs. Industrial applications of NCs have been avoided due to the aforementioned issues. In this study, we developed a new method based on a modified self-microemulsifying drug delivery system (SMEDDS) for in situ NCs production within the gastrointestinal tract. This new methodology does not require purification and recovery steps and can preserve the morphology and the functionality of NCs. The in situ formed NCs of Eudragit® RL PO were compared with nanospheres (NEs) in order to obtain evidence of their core-shell structure. NCs presented a spherical morphology with a size of 126.2 ± 13.1 nm, an ibuprofen encapsulation efficiency of 31.3% and a zeta-potential of 37.4 mV. Additionally, NC density and release profile (zero order) showed physical evidence of the feasibility of NCs in situ creation.

Liberación de pravastatina sódica formulada en matrices poliméricas a base de Quitosan/Pluronic F ̶ 127 / Release of pravastine sodium formulated in polymer chitosan/pluronic f-127 matrices

Introducción: el desarrollo de medicamentos transdérmicos manifiesta gran interés en los últimos años debido a las ventajas que ofrece; sin embargo, muchos de los sistemas desarrollados utilizan componentes solubles lo cual podría llevar a una ineficacia terapéutica si la matriz polimérica del sistema se solubiliza muy rápido, por ello se ensayan polímeros insolubles que permitan modular la liberación de un ingrediente farmacéuticamente activo. Objetivo: evaluar la liberación de pravastatina sódica en matrices poliméricas insolubles de quitosan/PF-127 con el método de paleta sobre disco para obtener su perfil cinético de liberación, con la finalidad de proponerse como matrices viables para la elaboración de parches transdérmicos. Métodos: se realizaron estudios de contenido químico, diámetro y espesor de las películas, calorimetrías de barrido diferencial y estudios de liberación. La cuantificación del principio activo se realizó mediante espectrofotometría UV-Vis a 238 nm. Resultados: se obtuvieron parches transdérmicos con buena uniformidad de contenido, espesor, diámetro, con una buena estabilidad en base a los estudios de calorimetría. El uso de PF-127 incrementó o retardó la liberación de pravastatina de la matriz polimérica dependiendo de su concentración y al realizarse los perfiles cinéticos de liberación las formulaciones se ajustaron a una cinética de orden 0 que describe el comportamiento de algunos sistemas transdérmicos. Conclusiones: los resultados manifiestan la posibilidad de usar esta matriz polimérica insoluble de quitosana con PF-127 para modular la liberación de pravastatina sódica y de fármacos con estructura similar a la misma por vía transdérmica, lo que generará de esta manera nuevas alternativas a las formas farmacéuticas orales para el tratamiento de padecimientos y enfermedades(AU)

Introduction: the development of transdermal drugs has aroused great interest in recent years due to their advantages, however many of the drug delivery systems use soluble matrix components which could trigger therapeutic problems due to a rapid release of the active ingredient. Therefore, insoluble polymers are being tested that can modulate the release of a pharmaceutically active ingredient. Objective: to evaluate the release of pravastatin sodium in insoluble polymer chitosan/PF-127 matrices by VER to obtain kinetic profile of release in order to submit them as viable systems for the manufacture of transdermal patches. Methods: studies on the chemical content, diameter and thickness of films, differential scanning calorimetry and release studies were performed. The UV-Vis spectrophotometry at 238 nm allowed quantitating the active principle. Results: transdermal patches with adequate uniform drug content, suitable thickness and diameter with good stability, based on calorimetric studies, were obtained. The use of PF-127 increased or delayed the release of pravastatin sodium from the polymeric matrix depending on concentration. When performing the kinetic profiles of release, the formulations were regulated to zero kinetic that describes the behavior of some transdernal systems. Conclusions: the results demonstrated the possibility of using these insoluble polymer chitosan/PF-127 matrices to modulate the release of pravastin sodium and of other structurally similar drugs, thus creating new alternatives to existing pharmaceutical oral forms for treatment of diseases(AU)

Principales superdisgregantes sintéticos, mecanismos y factores que influyen en su actividad / Major synthetic superdisintegrants, mechanisms and factors influencing their activity

Los superdisgregantes han despertado cierto interés en cuanto a que promueven mayor biodisponibilidad para ciertos fármacos. Los superdisgregantes son sustancias que se añaden a una formulación con el fin de romper o disgregar un comprimido en pequeñas partículas para disolver más rápido el principio activo. Esta revisión muestra una descripción general de sus mecanismos de acción, ventajas y desventajas y los superdisgregantes sintéticos más utilizados en la actualidad.

Superdisintegrants have sparked some interest in terms of promoting greater bioavailability for certain drugs. Superdisintegrants are substances added to a formulation in order to break or disintegrate the tablet into smaller particles that dissolve more rapidly the active ingredient. This review shows an overview of their mechanisms of action, advantages and disadvantages and synthetic superdisintegrants currently most used.

Preparation and characterization of solid lipid nanoparticles containing cyclosporine by the emulsification-diffusion method.

Solid lipid nanoparticles (SLNs) have been used for carrying different therapeutic agents because they improve absorption and bioavailability. The aim of the study was to prepare lipidic nanoparticles containing cyclosporine (CyA) by the emulsification-diffusion method and to study their physicochemical stability. Glyceryl behenate (Compritol(®) ATO 888) and lauroyl macrogolglycerides (Gelucire(®) 44/14) were used as carrier materials. Nanoparticles with good stability were obtained with Gelucire(®), while it was difficult to obtain stable systems with Compritol(®). Systems with Gelucire(®) were characterized by particle size, Z-potential, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), entrapment efficiency and in vitro release. Particle size and Z-potential were evaluated for at least three months. With a high CyA content (≥60 mg) in Gelucire(®) SLNs, variations in size were greater and particle size also increased over time in all batches; this effect may have been caused by a probable expulsion of the drug due to the lipid's partial rearrangement. While the Z-potential decreased 10 mV after three months, this effect may be explained by the superficial properties of the drug that make the molecules to be preferably oriented at the solid-liquid interface, causing a change in the net charge of the particle. SEM confirmed size and shape of the nanoparticles. DSC studies evidenced that CyA affects the lipid structure by a mechanism still unknown. The entrapment efficiency was higher than 92%, and CyA release from SLNs was relatively fast (99.60% in 45 min).

Un cultivo de levadura (saccharomyces cerevisiae) y la monensina sódica en el comportamiento productivo de ovinos / Effects of monensin and yeast culture (sacharomyces cerevisiae) treatment on sheep performance

Se evaluaron los efectos de la combinación de un cultivo de levadura y un ionóforo en el consumo, ganancia de peso y eficiencia de ovinos en finalización, alimentados con una dieta elaborada basada en forraje (50 por ciento) y concentrado (50 por ciento). El experimento se realizó en la granja experimental del Colegio de Postgraduados, estado de México (altitud de 2240 m), con clima templado subhúmedo con lluvias en verano, época seca en invierno, con temperatura media anual de 15,2°C y 650 mm de precipitación promedio anual. Se usaron 12 borregos alimentados en forma individual los cuales fueron distribuidos de acuerdo a un diseño completamente al azar con arreglo factorial (2 x 2) en los siguientes tratamientos: grupo testigo (T), Saccharomyces cerevisiae 1 g/kg de alimento (Sc), monensina 0,1 g/kg de alimento (Mo), y la combinación de ambos aditivos (Sc-Mo). Se uso el peso inicial como covariable. Los ovinos en el tratamiento testigo tuvieron la menor ganancia diaria de peso (189ª g/día), sin embargo, no se encontraron diferencias significativas (P<0,05) entre los diferentes aditivos o su combinación (Sc 231 elevado a la b), 220 elevdo a la b Sc-Mo). Los borregos con el Sc alcanzaron el mayor (P<0,05) consumo de alimentos (Kg)/día 1,36ª), mientras que Sc-Mo presentó los valores más bajos para esa variable (1,12 elevado a la c); los otros tratamientos tuvieron valores intermedios (T 1,27 elevado a la b) y Mo 1,23 elevado a la b). La conversión alimenticia se mejoró con la adición de los dos aditivos (Sc-Mo, 6,05ª) seguida de Mo (6,05 elevado a la ab) y T (6,76ª). El uso de monensina sódica con Saccharomyces cerevisae mejoró la ganancia de peso y la conversión alimenticia de ovinos con dietas con una relación 50:50 de forraje concentrado