The gelling properties of Dillenia indica mucilage in benzyl benzoate emulgel formulations

Abstract The objective of the study was to evaluate the gelling properties of Dillenia indica mucilage in benzyl benzoate emulgel formulation. Mucilage was extracted from the fruits of Dillenia indica using established methods and characterized by rheology and swelling. Emulsion (F1) was prepared using the continental emulsification method. Gelling agents (2 %w /v) were prepared by dispersing in distilled water with constant stirring at a moderate speed using a magnetic stirrer. F1 was added to the gel (0-75 %w /w) to obtain emulgel formulations and evaluated using viscosity, globule size, pH, release profiles and kinetic modeling. Data were expressed as mean ± SD, and similarity factor (f2) was used to compare all formulations. Formulation viscosity was significantly higher with carbopol than with Dillenia; globule sizes increased with concentration of gelling agents, and pH reduced as the concentration of Dillenia increased. All formulations showed controlled release properties with t80 ranging between 114 and 660 min. The release was governed by Korsmeyer-Peppas model. Formulation F5 prepared with 50 % Dillenia showed highest similarity to F4 prepared with 75 %w /w carbopol. Dillenia indica demonstrated acceptable gelling properties comparable with that of carbopol and could be improved for use in emulgel formulations.

Characterization and identification of ascorbyl methylsilanol pectinate for cosmetic formulations application

The ascorbyl methylsilanol pectinate (AMP) presents the same functional properties of ascorbic acid (AA). Besides antioxidant and depigmentant activity, the AMP presents silanol in its chemical structure. The aim of this work was to characterize and indentify the AMP alone and in cosmetic formulations. The following techniques were employed: Fourier Transform Infrared Spectrophotometry, particle size distributions, in vitro antioxidant activity with 2.2-diphenyl-1-picrylhydrazyl (DPPH) and Oxigen Radical Absorbance Capacity Assay and High Performace Liquid Chromatography (HPLC) (developed and validated method) for the active ingredient; Microscopy, HPLC and Normal Stability Assay (NSA) for the emulsions. Particle size distributions results showed that the average size of AMP was 1.0 µm and polydispersity index was 0.1. In DPPH assay AA and AMP were statistically the same. The value of ORAC obtained for AMP was 0.74 and for AA in the literature was 0.95. In the NSA the formulations were stable in conditions of 5.0 and 45.0 ± 2.0 ºC for 90 days. Adequate stability at ambient temperature out of reach of light was also observed. Thus, this works presented an acceptable method for quantification of AMP alone and in cosmetic formulations. AMP was an adequate choice for the incorporation in emulsions with antioxidant efficacy.

Optimization of cosmetic formulations development using Box-Behnken design with response surface methodology: physical, sensory and moisturizing properties

Considering the importance of an adequate composition of the formulation in the development of stable, safe and effective cosmetic products, experimental design techniques are tools that can optimize the formulation development process. The objective of this study was to develop topical formulations using the Box-Behnken design with response surface methodology and evaluate its physical, sensory and moisturizing properties. The experimental design used in the first step allowed to identify and to quantify the influence of raw materials, as well as the interaction between them. In the second step, the analysis identified the influence of soy lecithin, the phytantriol and capric acid triglyceride and caprylic on the consistency index, stickiness and greasiness and skin hydration. Cetearyl alcohol, dicetyl phosphate and cetyl phosphate 10EO and acrylates/C10-30 alkylacrylate crosspolymer showed effects in rheological parameters. The addition of soy lecithin had significant effects in terms of consistency index, stickiness, oiliness and immediate moisturizing effects. Phytantriol showed effects on increasing consistency index and oiliness sensation. Thus, the experimental design was shown to be an effective tool for research and development of cosmetics, since it allowed the assessment of the individual and interaction effects of raw materials in the responses: rheological parameters, sensory and clinical efficacy.

Nanoemulsion containing caffeine for cellulite treatment: characterization and in vitro evaluation

The Ginoide Hydrolipodystrophy (GHLD), commonly known as cellulite, occurs in 80-90% of the female population after the puberty period and comes from a metabolic modification in the cutaneous adipose tissue. Caffeine has been used in topical formulations due to its lipolytic action. We studied a nanoemulsion (F3) containing caffeine with two surfactants (oleth-3 and oleth-20) by emulsification method by phase inversion temperature inversion (PIT). The polydispersion indices (PDI) showed the reduced deviation of 0.1. The mean droplet size was ~ 40 nm. The evaluated constant of Ostwald, in the refrigerator condition was the most favorable during the stability test. In the In Raman spectroscopy assay, the caffeine bands found in F3 were compatible with those found in the caffeine solution (1337, 652.5 and 558.2 cm-1). There was no interaction of caffeine anhydrous with other ingredients in nanoemulsion. In the in vitro safety assay the result of 1.4 ranked the F3 as slightly irritating. In the natural membrane, cutaneous permeation test (human skin) permeate concentrations did not exceed the saturation concentration of the PBS buffer (48.96 µg/3 mL). The caffeine solution and F3 permeated statistically equal, but the nanoemulsion visually and sensorially improved the caffeine precipitation.

Stability and in vivo efficiency of natural cosmetic emulsion systems with the addition of vegetable oils

The aim of the paper is to test stability and biophysical properties of hydrophilic and lipophilic emulsions with selected vegetable seed oils: Limnanthes alba, Prunus amygdalus dulcis, Cannabis sativa, Rosa rubiginosa and Hellianthus annuus. Biophysical properties of emulsions are investigated in vivo using non-invasive instrumental methods (corneometry, tewametry and pH) in a group of 12 healthy women volunteers. Their stability profiles (colour, phase separation and centrifugation) under various temperatures (9, 25, 37 and 57 °C) and storage time (24 hours, 2, 7, 14, 21 and 28 days) were monitored. The moisturising activities of the emulsions supplemented with various oils were comparable. The lipophilic emulsions showed a better ability to improve the condition of the skin barrier due to formation of a surface lipid film. The tested formulations regulated the pH of the skin towards neutral values. Lipophilic emulsions showed earlier phase separation and changes in colour. The greatest resistance to thermal stress during storage was observed for the emulsion bases. Emulsions containing oils, except for those with rosehip and hempseed oils, were stable up to the temperature of 37 °C. The studied emulsion systems are excellent vehicles of vegetable oils and exhibit relatively good stability, benefiting the natural properties of skin.

Use of Opuntia ficus-indica (L. ) Mill extracts from Brazilian Caatinga as an alternative of natural moisturizer in cosmetic formulations

ABSTRACT The aim of this work was the obtainment of Opuntia fícus-indica (L.) Mill extract for the development of cosmetic formulations and in vivo evaluation of its moisturizing effects. The formulations were tested for preliminary and accelerated stability. Organoleptic characteristics, pH values and rheological behavior were assessed. The evaluation of moisturizing efficacy of the emulsions formulated with 3.0% of Polyacrylamide (and) C13-14 Isoparaffin (and) Laureth-7 containing 1.0 and 3.0% of O. ficus-indica hydroglycolic extract (EHG001) was performed using the capacitance method (Corneometer(r)) and the transepidermal water loss - TEWL evaluation (Tewameter(r)). The emulsions formulated were stable, exhibiting pseudoplastic and thixotropic behavior. The results of evaluation of moisturizing efficacy showed increased skin hydration after five hours by mainly increasing the skin barrier effect. The formulations containing 1.0 and 3.0% of EHG001 enhanced the skin barrier effect by reducing TEWL up to four hours after application. The results observed suggest that O. ficus-indica hydroglycolic extract may act through a humectant and occlusion mechanism.

Phenobarbital loaded microemulsion: development, kinetic release and quality control

ABSTRACT This study aimed to obtain and characterize a microemulsion (ME) containing phenobarbital (PB). The PB was incorporated in the proportion of 5% and 10% in a microemulsion system containing Labrasol(r), ethanol, isopropyl myristate and purified water. The physicochemical characterization was performed and the primary stability of the ME was evaluated. An analytical method was developed using spectrophotometry in UV  = 242 nm. The kinetics of the in vitro release (Franz model) of the ME and the emulsion (EM) containing PB was evaluated. The incorporation of PB into ME at concentrations of 5 and 10% did not change pH and resistance to centrifugation. There was an increase in particle size, a decrease of conductivity and a change in the refractive index in relation to placebo ME. The ME remained stable in preliminary stability tests. The analytical method proved to be specific, linear, precise, accurate and robust. Regarding the kinetics of the in vitro release, ME obtained an in vitro release profile greater than the EM containing PB. Thus, the obtained ME has a potential for future transdermal application, being able to compose a drug delivery system for the treatment of epilepsy.

RESUMO O objetivo deste trabalho foi obter e caracterizar uma microemulsão (ME) contendo fenobarbital (FEN). O FEN foi incorporado na proporção de 5% e 10% em um sistema microemulsionado composto por labrasol(r), etanol, miristato de isopropila e água purificada. Foi realizada a caracterização físico-química e avaliada a estabilidade preliminar da ME. Desenvolveu-se um método analítico por espectrofotometria em UV  = 242 nm. Foi avaliada a cinética de liberação in vitro (em modelo de Franz) da ME e da emulsão (EM) contendo FEN. A incorporação do FEN em ME nas concentrações de 5 e 10% não alterou o pH e a resistência à centrifugação. Houve aumento do tamanho da partícula, redução da condutividade e alteração do índice de refração em relação à ME placebo. A ME manteve-se estável nos ensaios de estabilidade preliminar. O método analítico demonstrou ser específico, linear, preciso, exato e robusto. Na cinética de liberação in vitro, a ME obteve um perfil de liberação in vitro superior a EM contendo FEN. Desta forma, a ME obtida tem potencial para uma futura aplicação transdérmica, podendo compor um sistema de liberação de fármacos para tratamento da epilepsia.

Particle size and morphological characterization of cosmetic emulsified systems by Optical Coherence Tomography (OCT)

ABSTRACT The physicochemical attributes of emulsified systems are influenced by the characteristics of their internal phase droplets (concentration, size and morphology), which can be modified not only by the formulation components, but also by the analytical methodology employed. Thus, the aim of this work involved the physicochemical characterization of cosmetic emulsions obtained from different surfactants, as well as the introduction of the optical coherence tomography (OCT) as the analytical technique employed for the morphological characterization and particle size determination of the formulations. Three emulsions were prepared, differing at the type and concentration of the surfactant used, and their droplet sizes were evaluated through optical microscopy, laser diffraction and OCT. The microscopic analysis and the laser diffraction techniques provided an average particle size minor than 6.0 µm, not detected by the OCT technique, which could identify only bigger particles of the emulsified systems' internal phase. The results testify that OCT was suitable for the morphological characterization of cosmetic emulsions; however, the technique needs to be improved to ensure a better sensitivity in the analysis of smaller particles.

RESUMO Os atributos físico-químicos de sistemas emulsionados são influenciados pelas características de suas gotículas de fase interna (concentração, tamanho e morfologia), as quais podem ser modificadas não apenas pelos componentes da formulação, mas também pela metodologia analítica empregada. Desta forma, o objetivo deste trabalho envolveu a caracterização físico-química de emulsões cosméticas obtidas a partir de diferentes tensoativos, bem como a introdução da tomografia de coerência óptica (OCT) como a técnica analítica utilizada para a caracterização morfológica e determinação do tamanho de partícula das formulações. Três emulsões foram preparadas, diferindo no tipo e concentração do tensoativo empregado, e seus tamanhos de gotícula foram avaliados por meio das técnicas de microscopia óptica, difração a laser e OCT. As técnicas de microscopia óptica e difração a laser forneceram tamanhos de partícula médios menores de 6.0 µm, não detectados pela técnica de OCT, que permitiu apenas a identificação de partículas maiores pertencentes à fase interna dos sistemas emulsionados. Os resultados reforçam a introdução da OCT como metodologia promissora para a caracterização morfológica de emulsões cosméticas; no entanto, a técnica requer aprimoramento para garantir maior sensibilidade na análise de partículas de menor tamanho.

Characterization and stability studies of emulsion systems containing pumice

Emulsions are the most common form of skin care products. However, these systems may exhibit some instability. Therefore, when developing emulsions for topical application it is interesting to verify whether they have suitable physical and mechanical characteristics and further assess their stability. The aim of this work was to study the stability of emulsion systems, which varied in the proportion of the emulsifying agent cetearyl alcohol (and) sodium lauryl sulfate (and) sodium cetearyl sulfate (LSX), the nature of the oily phase (decyl oleate, cyclomethicone or dimethicone) and the presence or absence of pumice (5% w/w). While maintaining the samples at room temperature, rheology studies, texture analysis and microscopic observation of formulations with and without pumice were performed. Samples were also submitted to an accelerated stability study by centrifugation and to a thermal stress test. Through the testing, it was found that the amount of emulsifying agent affects the consistency and textural properties such as firmness and adhesiveness. So, formulations containing LSX (5% w/w) and decyl oleate or dimethicone as oily phase had a better consistency and remained stable with time, so exhibited the best features to be used for skin care products.

Emulsões são a forma de apresentação mais comum dos produtos para aplicação na pele. No entanto estes sistemas podem exibir alguma instabilidade. Por esta razão, quando do desenvolvimento de emulsões para aplicação tópica é importante verificar se estas apresentam propriedades físicas ou mecânicas adequadas e avaliar a sua estabilidade. O objetivo deste trabalho consistiu no estudo da estabilidade de emulsões, cujas variações entre elas foi a proporção de agente emulsificante álcool estearílico (mais) laurilsulfato de sódio (mais) estearilsulfato de sódio (LSX), a natureza da fase oleosa (decil oleato, ciclometicona ou dimeticona) e a presença ou ausência de pedra-pomes (5% m/m). Mantendo as amostras à mesma temperatura, realizaram-se o estudo da reologia, a análise de textura e observação microscópica das formulações com e sem pedra-pomes. Amostras foram, também, submetidas a estudo de estabilidade acelerada por centrifugação e a ensaio de estresse térmico. Através dos testes realizados, constatou-se que a quantidade de agente emulsificante influencia a consistência e as propriedades de textura, como a firmeza e a adesividade. As formulações contendo LSX (5% m/m) e decil oleato ou dimeticona como fase oleosa exibiram melhores caraterísticas como produtos para aplicação na pele, uma vez que estas formulações apresentaram menor firmeza e consistência e permaneceram estáveis com o tempo.

Determination of the critical hydrophile-lipophile balance of licuri oil from Syagrus coronata: application for topical emulsions and evaluation of its hydrating function

The aims of this study were to determine the critical hydrophile-lipophile balance (HLB) of licuri oil, and to perform a clinical assay to evaluate its hydrating effects. For the determination of the HLB, serial emulsions were prepared with the oil. Regarding the clinical study, 13 human subjects were recruited to evaluate the hydrating power of the emulsified preparation containing licuri oil, and comparing it with the same preparation containing sweet almond oil (SAO). The critical HLB of licuri oil was represented by the zones within the concentrations of 10% for the oil and 15% for the pair of tensoactive agents, with a value of 11.8. Both preparations showed similar hydrating power. We propose that licuri oil can be considered a new lipophilic adjuvant with hydrating characteristics, which can be used in cosmetic preparations, replacing consecrated oils, such as SAO.

O objetivo deste estudo foi determinar o EHL crítico do óleo licuri e realizar um ensaio clínico para avaliar os seus efeitos hidratantes. Para a determinação do EHL foram preparadas emulsões seriadas contendo esse óleo. Em relação ao estudo clínico, avaliamos o poder hidratante de preparação emulsionada com óleo de licuri, comparando-a com a mesma preparação contendo óleo de amêndoas doces (OAD), em 13 voluntários. O EHL crítico do óleo de licuri foi representado pelas zonas dentro das concentrações de 10% para o óleo e 15% para o par de tensoativos, com um valor de 11,8 e ambas as preparações mostraram poder hidratante similar. Desta forma, o óleo de licuri pode ser considerado um novo adjuvante lipofílico com função hidratante, o qual pode ser usado em preparações cosméticas, substituindo óleos de consagrado uso, tais como o OAD.

Development, characterization and antioxidant activity of polysorbate based O/W emulsion containing polyphenols derived from Hippophae rhamnoides and Cassia fistula

The objective of this study was to develop a pharmaceutical O/W emulsion containing plant-derived polyphenol extracts and evaluate its stability and antioxidant activity. O/W emulsions were prepared using ionic surfactant polysorbate 80 (Tween 80®). The odorwas adjusted with few drops of blue sea fragrance. DPPH (1,1-diphenyl-2-picrylhydrazyl) assay was used to evaluate the antioxidant activity of the plant extracts alone and emulsions containing these extracts. Physical stability was assessed by submitting the emulsions to storage at 8 ºC, 25 ºC, 40 ºC and 40 ºC + 70% RH (relative humidity) for two months. Various physical characteristics of emulsions monitored, include color, creaming, liquefaction, centrifugation and pH. Brookfield rotational rheometer was used to determined viscosities and rheological behavior of emulsions. Different types of emulsion were determined microscopically, while pH values of emulsions were measured by a pH meter. Electrical conductivity data confirmed that the outer phase was water. Samples presented an acceptable pH value for an external topical use. Shear thinning behaviour was observed for all emulsions. The polyphenol-rich-plant-derived extracts alone and the extract containing emulsions showed good antioxidant activities. This research confirmed that the method used was suitable for preparing emulsions with Hippophae rhamnoids and Cassia fistula extracts, suggesting that those emulsions are suitable for topical use.

O presente estudo objetivou o desenvolvimento de uma emulsão farmacêutica óleo-água contendo extratos de plantas ricos em polifenóis, a comparação à sua formulação-controle e a avaliação de sua estabilidade, assim como de sua capacidade antioxidante. Extrato concentrado de Hippophae rhamnoids e Cassia fistula foi encapsulado no interior da fase oleosa da emulsão O/W. As emulsões foram preparadas usando o tensoativo iônico monooleato sorbital de polioxietileno (Tween 80®). O odor foi ajustado pela adição de algumas gotas de fragrância azul do mar. O ensaio do DPPH (1,1-difenil-2-picrilidrazil) foi utilizado para avaliar a atividade antioxidante dos extratos de plantas sozinhos e nas emulsões contendo os extratos. A estabilidade física foi avaliada submetendo os cremes a diferentes temperaturas de estocagem, como a 8 ºC, 25 ºC e 40 ºC e a 40% + 70% de umidade relativa por um período de 2 meses. As características físicas das emulsões foram monitoradas por 2 meses incluindo cor, cremosidade, liquefação, centrifugação e pH. O reômetro rotacional de Brookfield foi utilizado para determinar a viscosidade e o comportamento reológico das emulsões. O programa Rheocalc Brookfield foi utilizado para análise dos dados. As características organolépticas também foram avaliadas. O tipo de emulsão foi determinado microscopicamente, enquanto o pH das emulsões foi avaliado por meio de um pHmetro. A estabilidade farmacêutica esperada das emulsões foi alcançada dentro dos dois meses de estudo. Os resultados da condutividade elétrica confirmaram que a fase externa da emulsão era composta de água. O pH das amostras estava dentro da normalidade para uso tópico. A emulsão apresentou boa fragrância e pode ser retirada da pele com água após a aplicação, características desejáveis em emulsões O/W. Os extratos vegetais ricos em polifenóis isolados ou nas emulsões apresentaram boa atividade antioxidante. Nossos estudos confirmaram que o método utilizado foi adequado para preparar a emulsão semi-sólida contendo extratos de Hippophae rhamnoids e Cassia fistula. Nossos achados sugerem que emulsões contendo extratos de Hippophae rhamnoids e Cassia fistula são adequados para o uso tópico.

Bases dermatológicas utilizadas en preparados magistrales para ácne y rosácea / Dermatological vehicles utilized in masterly preparations for acne and rosacea

Las bases dermatológicas son preparaciones semisólidas que están destinadas a la aplicación de medicamentos en forma externa. La prescripcón de recetas magistrales permite a los dermatológos individulaizar en forma adecuada las terapias de sus pacientes. Las bases pueden ser clasificadas según su composición en: bases oleaginosas, bases de absorción, emulsiones (aceite/agua, agua/aceite), bases hidrosolubles y geles. Por su bajo o nulo contenido en materia grasa, las bases más indicadas en acné o rosácea son las emulsiones de aceite en agua, las bases hidrosolubles, elaboradas con polietilenglicoles, y los geles. Es importante tener presente la posibilidad de interacciones o incompatibilidades entre diversos principios activos y las bases

Estabilidad fisica de emulsiones espontaneas / Physical stability of spontain emulsions

En este trabajo, se determinó la influencia que tiene la presencia de estados mesomórficos, en sistemas heterogéneos, contentivos de agentes tensioactivos de tipo no-iónicos, sobre los cambios físicos en la fase interna, a diferentes temperaturas. Las variaciones estudiadas, se fundamentaron en las diferencias significativas de las muestras en cuanto a tamaño y número de gotículas cuando se sometieron a stress de temperatura. La evaluación se realizó utilizando el método conductimétrico, Coulter Counter. En este trabajo, se enfatiza la correlación de los estados mesomórficos con la espontaneidad y estabilidad física de las emulsiones

Emulsiones: aspectos físico-químicos / Emulsions: physico-chemical aspects

Se ha estudiado la influencia de la formulación físico-química (salinidad de la fase acuosa, EACN del aceite, naturaleza del surfactante, naturaleza y concentración del cosurfactante), sobre la naturaleza y propiedades de los sistemas Surfactante-Alcohol-Agua-Aceite emulsionados. Dicha influencia se muestra en un diagrama bidimensional mixto generalizado (Formulación-Fracción volumétrica de fase acuosa, fw). A relaciones agua/aceite próximas a la unidad (30% 70%), la inversión depende fundamentalmente de la proporción volumétrica de las fases, es decir, está controlada por factores físicos. Basándose en los resultados obtenidos, se propone una clasificación general del tipo de emulsión, de acuerdo con la formulación óptima y las líneas de inversión. La existencia de correlaciones entre las diferentes variables de formulación en el óptimo, los fenómenos asociados y una regla lineal de mezclas, sugieren la utilización de un nuevo método de caracterización de surfactantes, más rápido y exacto que el método HLB. Experimentalmente se usan uno o dos surfactantes conocidos y el parámetro característico correspondiente, que puede ser el HLB, es independiente de las demás variables físico-químicas