Investigation of Guar Gum and Xanthan Gum Influence on Essential Thyme Oil Emulsion Properties and Encapsulation Release Using Modeling Tools.

This study explores the influence of hydrocolloid interactions between Guar Gum (GG) and Xanthan Gum (XG) on the stability and release dynamics of essential thyme oil emulsions. We systematically characterized six emulsions with varying GG and XG ratios, employing spray-drying techniques for the encapsulation process. The stability of the emulsions was quantitatively analyzed, revealing a marked decrease in stability rates correlated with higher initial emulsion activity (zero-order kinetic constant r = -0.972). Furthermore, this study demonstrated that emulsions with carefully optimized hydrocolloid ratios could achieve high encapsulation efficiency (74%) and controlled release profiles. Kinetic modeling and diffusion analyses elucidated that increased XG concentrations tend to reduce diffusivity, thereby enhancing emulsion stability. The effective diffusivity of the thyme oil within the emulsion matrix was determined to be within a range of 0.7 to 2.4 × 10-10 m2/s, significantly influencing release kinetics. The Pearson correlation matrix underlined a substantial negative association between emulsion activity and effective diffusivity (r = -0.740), indicating that denser hydrocolloid networks impede oil mobility. The findings conclusively establish that the interplay of GG and XG concentrations is pivotal in dictating the emulsion's physicochemical properties, with denser networks formed by higher XG content leading to slower oil release rates and enhanced stability. This research provides critical insights for the design of encapsulated food and pharmaceutical products, highlighting the imperative of strategic hydrocolloid selection to realize specific functional attributes and performance criteria.

Liposomes Loaded with Green Tea Polyphenols-Optimization, Characterization, and Release Kinetics Under Conventional Heating and Pulsed Electric Fields.

This study aimed to increase the encapsulation efficiency (EE%) of liposomes loaded with green tea polyphenols (GTP), by optimizing with response surface methodology (RSM), characterizing the obtained particles, and modeling their release under conventional heating and pulsed electric fields. GTP-loaded liposomes were prepared under conditions of Lecithin/Tween 80 (4:1, 1:1, and 1:4), cholesterol (0, 30, and 50%), and chitosan as coating (0, 0.05, and 0.1%). Particles were characterized by size, polydispersity index, ζ-potential, electrical conductivity, and optical microscopy. The release kinetics was modeled at a temperature of 60 °C and an electric field of 5.88 kV/cm. The optimal manufacturing conditions of GTP liposomes (ratio of lecithin/Tween 80 of 1:1, cholesterol 50%, and chitosan 0.1%) showed an EE% of 60.89% with a particle diameter of 513.75 nm, polydispersity index of 0.21, ζ-potential of 33.67 mV, and electrical conductivity of 0.14 mS/cm. Optical microscopy verified layering in the liposomes. The kinetic study revealed that the samples with chitosan were more stable to conventional heating, and those with higher cholesterol content were more stable to pulsed electric fields. However, in both treatments, the model with the best fit was the Peppas model. The results of the study allow us to give an indication of the knowledge of the behavior of liposomes under conditions of thermal and non-thermal treatments, helping the development of new functional ingredients based on liposomes for processed foods.

Determination of the Dissolution/Permeation and Apparent Solubility for Microencapsulated Emamectin Benzoate Using In Vitro and Ex Vivo Salmo salar Intestine Membranes.

In this work, two microencapsulation techniques were used to protect and improve the absorption of emamectin benzoate (EB), which is an antiparasitic drug used to control Caligus rogercresseyi. EB has a low aqueous solubility, which affects its absorption in the intestine of Salmo salar. Microparticles were produced by spray drying and ionic gelation, using Soluplus® (EB−SOL) and sodium alginate (EB−ALG) as polymers, respectively. Studies were conducted on dissolution/permeation, apparent permeability (Papp), apparent solubility (Sapp), and absorption using synthetic and biological membranes. Based on these results, the amount of EB in the microparticles needed to achieve a therapeutic dose was estimated. The EB−ALG microparticles outperformed both EB−SOL and free EB, for all parameters analyzed. The results show values of 0.45 mg/mL (80.2%) for dissolution/permeation, a Papp of 6.2 mg/mL in RS−L, an absorption of 7.3% in RS, and a Sapp of 53.1% in EM medium. The EB−ALG microparticles decrease the therapeutic dose necessary to control the parasite, with values of 3.0−2 mg/mL and 1.1−2 mg/mL for EB in EM and RS, respectively. The Korsmeyer−Peppas kinetic model was the best model to fit the EB−ALG and EB−SOL dissolution/permeation experiments. In addition, some of our experimental results using synthetic membranes are similar to those obtained with biological membranes, which suggests that, for some parameters, it is possible to replace biological membranes with synthetic membranes. The encapsulation of EB by ionic gelation shows it is a promising formulation to increase the absorption of the poorly soluble drug. In contrast, the spray-dried microparticles produced using Soluplus® result in even less dissolution/permeation than free EB, so the technique cannot be used to improve the solubility of EB.

Quality Control Study of Different Products from Famotidine Tablets in the Iraqi Market / Estudio de Control de Calidad de Diferentes Productos de Tabletas de Famotidina en el Mercado Iraquí

Background: In developing countries, particularly in Iraq, the use of generic medicines has been increasing in recent years, primarily as a cost-saving measure in healthcare provision. In the Iraqi market, famotidine tablets are available from different pharmaceutical companies. As a result, regular pre-marketing quality testing is required to check the quality and identify which product might safely substitute the innovator product in the event of the innovator brand's unavailability or high cost. Objective: various quality control tests have been conducted to determine the Pharmaceutical Equivalence of the different generic and brands of Famotidine film-coated tablets marketed in Iraq. Materials and Methods: Four different samples of the most commonly available Famotidine 20 mg tablets in the Iraqi market were tested for drug contents, friability, and hardness. Additionally, the in-vitro drug release and kinetics were evaluated. Results: slight differences in the products' content were found; however, they were within the acceptable requirement of British Pharmacopeia (BP) and The United States Pharmacopoeia (USP) 30, NF 25. Similarly, the friability and hardness were within the excellent range according to the B.P. and USP. The results of our study indicated that the tested brand (Famodin) and the three generic products (Famosam, Ulceran, and Famodar) of Famotidine tablets have a unique pattern of in-vitro release profiles. However, all the tested brands and generic pills complied with the USP specifications for the immediate release dosage forms except for Famosam. Release kinetic for the four tested products indicates first-order kinetic models. Conclusion: The findings revealed that nearly all of the tested Famotidine tablet brands and generics met the pharmacopeial requirements for oral tablets. As a result, if acquiring the innovative brand of famotidine tablets is difficult to obtain, healthcare providers may be advised to use the tested products instead

Antecedentes: En los países en vías de desarrollo, especialmente en Irak, el uso de medicamentos genéricos ha aumentado en los últimos años, principalmente como medida de ahorro en la prestación de servicios sanitarios. En el mercado iraquí, los comprimidos de famotidina están disponibles en diferentes empresas farmacéuticas. Por ello, es necesario realizar periódicamente pruebas de calidad previas a la comercialización para comprobar la calidad e identificar qué producto podría sustituir con seguridad al producto innovador en caso de que éste no esté disponible o tenga un coste elevado. Objetivo: se han realizado varias pruebas de control de calidad para determinar la Equivalencia Farmacéutica de los diferentes genéricos y marcas de Famotidina comprimidos recubiertos con película comercializados en Irak. Materiales y métodos: Se analizaron cuatro muestras diferentes de los comprimidos de 20 mg de Famotidina más comunes en el mercado iraquí para determinar el contenido de fármaco, la friabilidad y la dureza. Además, se evaluó la liberación in-vitro del fármaco y su cinética. Resultados: Se encontraron ligeras diferencias en el contenido de los productos; sin embargo, estaban dentro de los requisitos aceptables de B.P. y de la Farmacopea de Estados Unidos (USP) 30, NF 25. Así mismo, la friabilidad y la dureza estaban dentro del rango excelente según la B.P. y la USP. Los resultados de nuestro estudio indicaron que la marca probada (Famodin) y los tres productos genéricos (Famosam, Ulceran y Famodar) de comprimidos de famotidina tienen un patrón único de perfiles de liberación in-vitro. Sin embargo, todas las marcas y los comprimidos genéricos probados cumplieron con las especificaciones de la USP para las formas farmacéuticas de liberación inmediata, excepto Famosam. La cinética de liberación de los cuatro productos probados indica modelos cinéticos de primer orden. Conclusiones: Los resultados revelaron que casi todas las marcas y genéricos de comprimidos de Famotidina probados cumplían los requisitos farmacopeicos para los comprimidos orales. En consecuencia, si resulta difícil adquirir la marca innovadora de comprimidos de famotidina, se puede aconsejar a los profesionales sanitarios que utilicen los productos probados en su lugar

Active PLA Packaging Films: Effect of Processing and the Addition of Natural Antimicrobials and Antioxidants on Physical Properties, Release Kinetics, and Compostability.

The performance characteristics of polylactic acid (PLA) as an active food packaging film can be highly influenced by the incorporation of active agents (AAs) into PLA, and the type of processing technique. In this review, the effect of processing techniques and the addition of natural AAs on the properties related to PLA performance as a packaging material are summarized and described through a systematic analysis, giving new insights about the relation between processing techniques, types of AA, physical-mechanical properties, barriers, optical properties, compostability, controlled release, and functionalities in order to contribute to the progress made in designing antioxidant and antimicrobial PLA packaging films. The addition of AAs into PLA films affected their optical properties and influenced polymer chain reordering, modifying their thermal properties, functionality, and compostability in terms of the chemical nature of AAs. The mechanical and barrier performance of PLA was affected by the AA's dispersion degree and crystallinity changes resulting from specific processing techniques. In addition, hydrophobicity and AA concentration also modified the barrier properties of PLA. The release kinetics of AAs from PLA were tuned, modifying diffusion coefficient of the AAs in terms of the different physical properties of the films that resulted from specific processing techniques. Several developments based on the incorporation of antimicrobial and antioxidant substances into PLA have displayed outstanding activities for food protection against microbial growth and oxidation.

Evaluation of eggshell membrane as an alternative biopolymeric matrix for delivery of nimesulide / Avaliação da membrana da casca do ovo como uma matriz biopolimérica alternativa para entrega de nimesulida / Evaluación de la membrana de la cáscara de huevo como una matriz de biopolímero alternativa para la administración de nimesulida

SUMMARY Introduction: Eggshell membrane (ESM) is a tissue found between the eggshell and the albumen of eggs that has attractive properties for use in drug delivery systems. Aim: To incorporate in ESM and used it as a model drug in release studies. The color change and FTIR analysis of the biopolymer proved the incorporation of nimesulide in ESM. Results: The drug uptake was 176.83 and 122.69 mg g-1 by natural and cross-linked ESM. Release studies were carried out using a spectrophotometric flow system in simulated intestinal fluid pH 7.4. The release profiles showed that after 60 minutes 54.55 and 42.58 % of the drug were released from natural and cross-linked ESM, respectively. Kinetics parameters indicated that drug release was better described by the Higuchi model and through a non-Fickian release. Conclusion: Considering these results is proved that ESM has the potential to become a polymeric matrix for drug release systems.

RESUMO Introdução: a membrana da casca do ovo (MCO) é um tecido encontrado entre a casca e o albúmen de ovos que possui propriedades atrativas para uso em sistemas de liberação de fármacos. Objetivo: incorporar à MCO e utilizá-la como fármaco modelo em estudos de liberação. Mudança de coloração e análises de FTIR do biopolímero comprovaram a incorporação da nimesulida na MCO. A incorporação do fármaco foi de 176,83 e 122,69 mg g-1 na MCO natural e reticulada, respectivamente. Resultados: os estudos de liberação foram realizados usando um sistema de fluxo espectrofotométrico em fluido intestinal simulado pH 7,4. Os perfis de liberação mostraram que após 60 minutos 54,55 e 42,58 % do medicamento foram liberados da MCO natural e reticulada, respectivamente. Os parâmetros cinéticos indicaram que a liberação do fármaco foi mais bem descrita pelo modelo de Higuchi e por meio de uma liberação não Fickiana. Conclusão: considerando estes resultados, fica comprovado que a MCO tem potencial para se tornar uma matriz polimérica para sistemas de liberação de fármacos.

RESUMEN Introducción: La membrana de cáscara de huevo (MCH) es un tejido que se encuentra entre la cáscara de huevo y la albúmina de los huevos que tiene propiedades atractivas para su uso en sistemas de administración de fármacos. Objetivo: Incorporar en MCH y utilizarla como fármaco modelo en estudios de liberación. El cambio de color y el análisis FTIR del biopolímero demostraron la incorporación de nimesulida en MCH. Resultados: La captación del fármaco fue de 176,83 y 122,69 mg g-1 por MCH natural y reticulado. Los estudios de liberación se llevaron a cabo utilizando un sistema de flujo espectrofotométrico en líquido intestinal simulado pH 7,4. Los perfiles de liberación mostraron que después de 60 minutos el 54,55 y el 42,58 % del fármaco se liberó de la MCH natural y reticulada, respectivamente. Los parámetros cinéticos indicaron que la liberación del fármaco se describió mejor mediante el modelo de Higuchi y mediante una liberación no Fickian. Conclusión: De acuerdo con estos resultados, el MCH tiene el potencial de convertirse en una matriz polimérica para sistemas de liberación de fármacos.

Synergic effects of ultrasound and ionic liquids on fluconazole emulsion.

The aim of this work was to evaluate the influence of US on the properties of the fluconazole emulsions prepared using imidazolium-based ILs ([Cn C1im]Br). The effects of the preparation method (mechanical stirring or US), US amplitude, alkyl chain length (of [C12C1im]Br or [C16C1im]Br), and IL concentration on the physicochemical properties were evaluated. Properties such as droplet size, span index, morphology, viscosity encapsulation efficiency, and drug release profile were determined. The results showed that US-prepared emulsions had a smaller droplet size and smaller polydispersity (Span) than those prepared by mechanical stirring. Additionally, the results showed that emulsions prepared with [C16C1im]Br and US had spherical shapes and increased stability compared to emulsions prepared by MS, and also depended on the IL concentration. The emulsion prepared by US at 40% amplitude had increased encapsulation efficiency. US provided a decrease in the viscosity of emulsions containing [C12C1im]Br; however, in general, all emulsions had viscosity close to that of water. Emulsions containing [C16C1im]Br had the lowest viscosities of all the emulsions. The emulsions containing the IL [C16C1im]Br had more controlled release and a lower cumulative percentage of drug release. The IL concentration required to prepare these emulsions was lower than the amount of conventional surfactant required, which highlights the potential synergic effects of ILs and US in preparing emulsions of hydrophobic drugs.

Effect of chia mucilage addition on oxidation and release kinetics of lemon essential oil microencapsulated using mesquite gum - Chia mucilage mixtures.

Lemon essential oil (LEO) emulsions were prepared using mesquite gum (MG) - chia mucilage (CM) mixtures (90-10 and 80-20 MG-CM weight ratios) and MG as control sample, LEO emulsions were thenspray dried for obtaining the respective microcapsules.LEO emulsions were analyzed by mean droplet size and apparent viscosity, while microcapsules were characterized through mean particle size, morphology, volatile oil retention (≤51.5%), encapsulation efficiency (≥96.9%), as well asoxidation and release kinetics of LEO. TheLEO oxidation kinetics showed that 90-10 and 80-20MG-CM microcapsules displayed maximum peroxide values of 91.6 and 90.5 meq hydroperoxides kg-1 of oil, respectively, without significant differences between them (p > .05).MG-CM microcapsules provided better protection to LEO against oxidation than those formed with MG; where the oxidation kinetics were well adjusted to zero-order (r2 ≥ 0.94).The LEO release kinetics from microcapsules were carried out at differentpH (2.5 and 6.5) and temperature (37 °C and 65 °C) and four mathematical models (zero-order, first-order, Higuchi and Peppas) were used to evaluate the experimental data; the release kinetics indicated that the 80-20 MG-CM microcapsules had a longer delay in LEO release rate, followed by 90-10 MG-CM and MG microcapsules, hence, CM addition in MG-CM microcapsules contributed to delay the LEO release rate. This work clearly demonstrates that use of a relatively small amount of CM mixed with MGimproves oxidative stability and delays the release rate of encapsulated LEO regarding MG microcapsules, therefore, MG-CM mixtures are interesting additives systems suitable for being applied in food industry.

Preparation and in vitro & in vivo evaluation of cephalexin matrix tablets

The purpose of the study is to develop cephalexin controlled-release matrix tablets by using lower proportions of release retardant polymer and to establish their in vitro & in vivo correlation. Tablets were compressed by incorporating polymers in a matrix form along with drug which prolong the drug release. Twelve formulations were prepared by mixing ethyl cellulose (EC) and hydroxypropyl methylcellulose (HPMC) (three different viscosity grades) in various proportions. F-1 to F-4 formulations were prepared by incorporating drug, HPMC K4M and ethyl cellulose in 100 : 5 : 5, 100 : 10 : 5, 100 : 15 : 5 and 100 : 20 : 5; similarly, F-5 to F-8 were prepared with HPMC K15M; and F-9 to F-12 were prepared with HPMC K100M using a wet granulation process maintained same proportions, along with drug and EC. Tablets were evaluated for their pre-compression and post-compression characteristics and they were found to be in limits. From the dissolution testing, F-4 showed 100.34% medicament release in 12 h. In vivo studies were conducted on rabbit and pharmacokinetic parameters of the optimized formulation were evaluated using HPLC method. It was found that matrix tablets showed increased t1/2 and decreased Kel. The design signified that the drug release rate from tablets was influenced by the small proportion (around 7% of a tablet weight) of polymer mixture and it controlled 100% medicament release upto 12 h effectively with the low grade viscosity of HPMC combination, with good in vitro & in vivo correlation.

In vitro evaluation of sustained released matrix tablets containing ibuprofen: a model poorly water-soluble drug

ABSTRACT A matrix system was developed that releases ibuprofen (IB) over a 12-hour period and the influence of the polymer type and concentration on the release rate of the drug was evaluated. Tablets containing different concentrations of Carbopol (CP), hydroxypropyl methylcellulose (HPMC), or ethyl cellulose (EC) were prepared using direct compression and the drug content, content uniformity, hardness, friability, dissolution performance, and in vitro release kinetics were examined. Formulated tablets were found to be within acceptable limits for physical and chemical parameters. The release kinetics of the Carbopol(r)971P 8% formulation showed the best linearity (r 2 =0.977) in fitting zero-order kinetics, suggesting the release rate was time independent. The drug release from tablets containing 8% CP was extended over approximately 18 hours and the release kinetics were nearly linear, suggesting that this system has the potential to maintain constant plasma drug concentrations over 12 hours, which could reduce the frequency of administration and the occurrence of adverse effects associated with repeated administration of conventional IB tablets.

Monolithic LC method applied to fesoterodine fumarate low dose extended-release tablets: Dissolution and release kinetics.

A dissolution test for fesoterodine low dose extended-release tablets using liquid chromatographic (LC) method equipped with a C18 monolithic column was developed and validated. LC system was operated isocratically at controlled temperature (40 °C) using a mobile phase of acetonitrile:methanol:0.03 M ammonium acetate (pH 3.8) (30:15:55, v/v/v), run at a flow rate of 1.5 mL/min and detected at 208 nm. The best dissolution conditions for this formulation were achieved using a USP apparatus 2 (paddle) at 100 rpm and 900 mL of phosphate buffer at pH 6.8 as the dissolution medium. Validation parameters such as the specificity, linearity, accuracy, precision, and robustness were evaluated according to international guidelines, giving results within the acceptable range. The kinetic parameters of drug release were also investigated using model-dependent methods and the dissolution profiles were best described by the Higuchi model. The validated dissolution test can be applied for quality control of this formulation.

Drug release mechanisms of chemically cross-linked albumin microparticles: effect of the matrix erosion.

Albumin (BSA) microparticles were developed as a biotechnological alternative for drug delivery. Vitamin B12 (Vit-B12) was used as a model drug. The microparticles were obtained from maleic anhydride-functionalized BSA and N',N'-dimethylacrylamide (DMAAm) in a W/O emulsion without and with PVA. The microparticles produced at 15min of stirring without PVA showed the best results in terms of size, homogeneity, and sphericity. In such a case, BSA played a role as a surface active agent, replacing PVA. For longer stirring times, BSA was unable to act as an emulsifier. These microparticles showed an uncommon release profile, consisting of a two-step release mechanism, at the pH range studied. Considering that a two-step release mechanism is occurring, the experimental data were adjusted by applying modified power law and Weibull equations in order to describe release mechanism n and release rate constant k, respectively. Each one of the release stages was related to a specific value of n and k. The second stage was driven by a super case II transport mechanism, as a result of diffusion, macromolecular relaxation, and erosion. A third model, described by Hixson-Crowell, confirmed the erosion mechanism. Vit-B12 diffusion kinetics in aqueous solutions (i.e., without the microparticles) follows a one-step process, being k dependent on the pH, confirming that the two-step release mechanism is a characteristic profile of the developed microparticles. The microparticles released only 2.70% of their initial drug load at pH 2, and 58.53% at pH 10.

Cefuroxime axetil loaded gastroretentive floating tabletsbased on hydrophilic polymers: preparation and in vitro evaluation

The aim of this work was to study the formulation and in vitro characterization of hydro dynamically balanced floating matrix tablets using Cefuroxime axetil (CA) as model drug. Different excipients such as hydroxy propyl methyl cellulose (HPMC) K15M, E5LV (gelling agent), sodium bicarbonate (gas generating agent) and sodium lauryl sulfate (SLS) (solubility enhancer) were used in order to optimize the drug release profile as well as floating property. Decrease in release characteristics with high viscous polymer were observed due to increased gel strength, tortuosity and length of drug diffusion path. Significant difference (p<0.5) in release rate was found at different concentration of SLS. The release mechanisms were explored and explained with zero order, first order, Higuchi, Korsmeyer and Hixson-Crowell equations. The release rate, extent and mechanism were governed by the content of polymer. The polymer content and amount of floating agent significantly affected the time required for 50%of drug release (t50%), mean dissolution time (MDT), release rate constant, and diffusion exponent (n).Kinetic modeling of dissolution profile revealed that the drug release mechanism could range from diffusion controlled to case II transport, which was co-dominated by diffusion polymer erosion in the release mechanism.