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1.
China Journal of Chinese Materia Medica ; (24): 6075-6081, 2023.
Article in Chinese | WPRIM | ID: wpr-1008806

ABSTRACT

With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.


Subject(s)
Polyethylene Glycols/chemistry , Castor Oil , Methanol , Surface-Active Agents/chemistry , Solvents , Water/chemistry , Emulsions/chemistry
2.
Arch. latinoam. nutr ; 72(3): 196-204, sept. 2022. tab
Article in Spanish | LILACS, LIVECS | ID: biblio-1399277

ABSTRACT

Introduction: The use of vegetable proteins as ingredients in food systems is based on their functional properties. The water and oil holding capacity, foaming, and emulsifying capacity/stability, and antioxidant assay of the protein fractions - albumins, globulins 7S/11S, glutelins and prolamins - isolated from Leucaena seed were evaluated. Objective: The objective of this study was to evaluate the functional properties and antioxidant capacity of the concentrate and protein fractions of ripe Leucaena spp. seeds. Materials and methods: Ripe Leucaena seeds were collected and evaluated in Oaxaca, Mexico (16°59'21''N 96°43'26''O) during the months of February-April 2021.The protein concentrate was isolated by isoelectric precipitation (pH=9, pH=4). The albumins, globulins, glutelins and prolamins were isolated based on their solubility properties in different extracting solutions. Results: Glutelins constituted the main protein fraction (75.88%). Prolamins were not found. The glutelins fractions showed the highest oil holding capacity (0.93±0.08 mL g-1). The albumins fraction had the highest water holding capacity (2.53±0.15 mL g-1), foaming capacity and foam stability (71.83±1.26 % and 70.00±0.00%, respectively) and antioxidant capacity (18.09±0.88%). The globulins exhibited the highest emulsifying capacity and emulsion stability (56.83±1.76% and 55.67±1.20%, respectively). Conclusions: The concentrate and protein fraction of Leucaena seeds showed different techno-functional and antioxidant properties of interest for the food industry, like those showed by other commercial vegetable proteins(AU)


Introducción: El uso de proteínas vegetales como ingredientes en sistemas alimentarios se basa en sus propiedades funcionales. Se evaluó la capacidad de retención de agua y aceite, la capacidad/estabilidad espumante y emulsionante y el ensayo antioxidante de las fracciones proteicas -albúminas, globulinas 7S/11S, glutelinas y prolaminas- aisladas de las semillas de Leucaena. Objetivo: El objetivo de este estudio fue evaluar las propiedades funcionales y la capacidad antioxidante del concentrado y las fracciones proteicas de las semillas maduras de Leucaena spp. Materiales y métodos: Las semillas maduras de Leucaena fueron recolectadas y evaluadas en Oaxaca, México (16°59'21''N 96°43'26''O) durante los meses de febrero-abril del año 2021. Se usó harina de Leucaena desgrasada para la preparación de las fracciones proteicas. El concentrado proteico se aisló por precipitación isoeléctrica (pH=9, pH=4). Las albúminas, globulinas, glutelinas y prolaminas se aislaron en función de sus propiedades de solubilidad en diferentes soluciones de extracción. Resultados: Las glutelinas constituyeron la principal fracción proteica (75,88%). No se encontraron prolaminas. La fracción de glutelinas mostró la mayor capacidad de retención de aceite (0.93±0,08 mL g-1). La fracción de albúminas presentó la mayor capacidad de retención de agua (2,53±0,15 mL g-1), capacidad espumante y estabilidad de la espuma (71,83±1,26% y 70,00±0,00%, respectivamente) y capacidad antioxidante (18,09±0,88%). Las globulinas mostraron la mayor capacidad emulsionante y estabilidad de la emulsión (56,83±1,76 y 55,67±1,20%, respectivamente). Conclusiones: El concentrado y las fracciones proteicas de las semillas de Leucaena mostraron diferentes propiedades tecno-funcionales y antioxidantes de interés para la industria alimentaria, similares a los reportados por diversas proteínas vegetales comerciales(AU)


Subject(s)
Plant Proteins, Dietary/chemistry , Fabaceae/chemistry , Antioxidants/chemistry , Seeds , Plant Oils/chemistry , Water/chemistry , Food Industry , Albumins/chemistry , Emulsions/chemistry , Globulins/chemistry , Glutens/chemistry
3.
China Journal of Chinese Materia Medica ; (24): 1230-1236, 2022.
Article in Chinese | WPRIM | ID: wpr-928047

ABSTRACT

A new quercetin nanocrystals self-stabilized Pickering emulsion(QT-NSSPE) was prepared by high-pressure homogenization combined with probe ultrasonic method. The influences of oil fraction, quercetin(QT) concentration, and pH of water phase on the formation of QT-NSSPE were investigated. On this basis, the QT-NSSPE prepared under optimal conditions was evaluated in terms of microstructure, stability, and in vitro release and the droplet size and drug loading were 15.82 μm and 4.87 mg·mL~(-1), respectively. The shell structure formed by quercetin nanocrystals(QT-NC) on the emulsion droplet surface was observed under a scanning electron microscope(SEM). X-ray diffraction(XRD) showed that the crystallinity of adsorbed QT-NC decreased significantly as compared with the raw QT. There were not significant changes of QT-NSSPE properties after 30 days of storage at room temperature. The in vitro release experiment confirmed that QT-NSSPE has a higher accumulative release rate than the raw QT. All these results indicated that QT-NSSPE has a great stability and a satisfactory in vitro release behavior, which is a promising new oral delivery system for QT.


Subject(s)
Emulsions/chemistry , Nanoparticles , Particle Size , Quercetin , Water/chemistry
4.
Braz. oral res. (Online) ; 34: e001, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089393

ABSTRACT

Abstract This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Subject(s)
Humans , Plant Oils/chemistry , Dental Bonding/methods , Dentin-Bonding Agents/chemistry , Dentin/drug effects , Fabaceae/chemistry , Surface Properties , Tensile Strength , Materials Testing , Chlorhexidine/chemistry , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Composite Resins/chemistry , Resin Cements/chemistry , Dental Cements/chemistry , Dental Leakage , Dentin/chemistry , Emulsions/chemistry
5.
Braz. oral res. (Online) ; 34: e001, 2020. tab, graf
Article in English | LILACS | ID: biblio-1055529

ABSTRACT

Abstract This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Subject(s)
Humans , Plant Oils/chemistry , Dental Bonding/methods , Dentin-Bonding Agents/chemistry , Dentin/drug effects , Fabaceae/chemistry , Surface Properties , Tensile Strength , Materials Testing , Chlorhexidine/chemistry , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Composite Resins/chemistry , Resin Cements/chemistry , Dental Cements/chemistry , Dental Leakage , Dentin/chemistry , Emulsions/chemistry
6.
Rev. chil. pediatr ; 86(4): 257-263, ago. 2015. graf
Article in Spanish | LILACS | ID: lil-764082

ABSTRACT

Objetivo: Analizar la evolución de los nacimientos y medidas antropométricas al nacer entre 1974-2011 en el Hospital de Limache, Región de Valparaíso, Chile. Pacientes y métodos: Se construyeron series de tiempo de nacimientos, peso y longitud al nacer, peso y talla baja al nacer. Se modelaron las tendencias con regresiones multivariadas usándose splines para representar los cambios de tendencia por década. Resultados: La serie comprende 17.574 nacimientos. Hubo un aumento de los nacimientos/año en los 70 (30/año) y disminución de 17 y 22 nacimientos/año en los 80 y 90 (p < 0,001); después, sin tendencia significativa. Los recién nacidos entre 2000-2011 registran 266 g más que los de la década de los 70 (p < 0,001), alcanzando actualmente en promedio 3.530 g. El bajo peso al nacer disminuyó de 8% en los 70 a 1,1% después de 2000. La longitud al nacer incrementó 1 cm en 37 años, con disminución de la talla baja de 7,6% a 2,1% en el periodo estudiado. Conclusión: Los nacimientos en el Hospital de Limache disminuyeron y las medidas antropométricas al nacer mejoraron; sin embargo, hay que considerar los posibles sesgos que distorsionan estas estimaciones.


Objective: To analyse the outcomes of births and anthropometric measurements at birth of children born between 1974 and 2011 at Limache Hospital (Valparaíso, Chile). Patients and method: Times series were constructed of births, weight and length at birth, and low weight and length at birth. The trend was modelled with linear and logistical regressions using splines to represent breaks in the trend by decade. Results: The series includes 17,574 births. There was an increase in births per year in the 1970s (30/year) and declines in them to 17 and 22 births/year in the 1980s and 1990s, respectively (P < .001), with no significant trend thereafter. Newborns from 2000 to 2011 weighed 266 grams more than those in the 1970s (P < .001), and have now reached a mean weight of 3,530 g. Low birthweight fell from 8% in the 1970s to 1.1% after 2000. Birth length increased by 1 cm in the 37 years studied, with a reduction of low birth length from 7.6% to 2.1% during the period. Conclusion: Live births in the Limache Hospital declined, and anthropometric measurements at birth improved in the years analysed. This information is useful in developing interventions, taking into account the possible selection biases that could distort these estimates and their interpretation.


Subject(s)
Animals , Apomorphine/chemistry , Prodrugs/chemistry , Administration, Oral , Drug Delivery Systems/methods , Emulsions/chemistry , Esters/chemistry , Hydrolysis , Lipids/chemistry , Pancreatic Extracts/chemistry , Swine
7.
Yonsei Medical Journal ; : 1524-1532, 2013.
Article in English | WPRIM | ID: wpr-100943

ABSTRACT

PURPOSE: Intravenous lipid emulsions have been used to treat the systemic toxicity of local anesthetics. The goal of this in vitro study was to examine the effects of lipid emulsions on the norepinephrine-mediated reversal of vasodilation induced by high doses of levobupivacaine, ropivacaine, and mepivacaine in isolated endothelium-denuded rat aorta, and to determine whether such effects are associated with the lipid solubility of local anesthetics. MATERIALS AND METHODS: The effects of lipid emulsions (0.30, 0.49, 1.40, and 2.61%) on norepinephrine concentration-responses in high-dose local anesthetic (6x10-4 M levobupivacaine, 2x10-3 M ropivacaine, and 7x10-3 M mepivacaine)-induced vasodilation of isolated aorta precontracted with 60 mM KCl were assessed. The effects of lipid emulsions on local anesthetic- and diltiazem-induced vasodilation in isolated aorta precontracted with phenylephrine were also assessed. RESULTS: Lipid emulsions (0.30%) enhanced norepinephrine-induced contraction in levobupivacaine-induced vasodilation, whereas 1.40 and 2.61% lipid emulsions enhanced norepinephrine-induced contraction in both ropivacaine- and mepivacaine-induced vasodilation, respectively. Lipid emulsions (0.20, 0.49 and 1.40%) inhibited vasodilation induced by levobupivacaine and ropivacaine, whereas 1.40 and 2.61% lipid emulsions slightly attenuated mepivacaine (3x10-3 M)-induced vasodilation. In addition, lipid emulsions attenuated diltiazem-induced vasodilation. Lipid emulsions enhanced norepinephrine-induced contraction in endothelium-denuded aorta without pretreatment with local anesthetics. CONCLUSION: Taken together, these results suggest that lipid emulsions enhance the norepinephrine-mediated reversal of local anesthetic-induced vasodilation at toxic anesthetic doses and inhibit local anesthetic-induced vasodilation in a manner correlated with the lipid solubility of a particular local anesthetic.


Subject(s)
Animals , Male , Rats , Amides/adverse effects , Anesthetics, Local/adverse effects , Bupivacaine/adverse effects , Emulsions/chemistry , Lipids/chemistry , Mepivacaine/adverse effects , Norepinephrine/therapeutic use , Rats, Sprague-Dawley , Vasodilation/drug effects
8.
Journal of Korean Medical Science ; : 827-829, 2012.
Article in English | WPRIM | ID: wpr-210919

ABSTRACT

Although rare, intraoperative anaphylaxis can lead to significant morbidity and mortality. Aquafol(R) (Daewon Pharmaceutical Co. Ltd., Seoul, Korea), a microemulsion propofol, was developed to eliminate lipid solvent-related adverse events, and was used in clinical anesthesia since 2009 with little data about severe side effects such as anaphylaxis. A healthy 16-yr-old male patient who had past medical history with two previous operations of no complications developed cardiovascular shock with generalized erythema following administration of microemulsion propofol during anesthesia induction. Intravenous injection of epinephrine and steroid rescued him. He remained in a stable state without any problems postoperatively and was discharged. Clinicians should consider this rare but serious complication during induction of anesthesia with propofol.


Subject(s)
Adolescent , Humans , Male , Anaphylaxis/chemically induced , Anesthetics, Intravenous/administration & dosage , Bronchodilator Agents/therapeutic use , Dexamethasone/therapeutic use , Emulsions/chemistry , Epinephrine/therapeutic use , Glucocorticoids/therapeutic use , Injections, Intravenous , Propofol/administration & dosage
9.
Article in Portuguese | LILACS | ID: lil-593792

ABSTRACT

Microemulsão (ME) é um sistema que foi descoberto por Hoar e Schulman no ano de 1943 e que é termodinamicamente estável e isotropicamente translúcido de dois líquidos imiscíveis (óleo/água), estabilizados por um filme interfacial de tensoativos. O estudo de sistemas microemulsionados se baseia nas suas três teorias de formação: (1) teoria da solubilização, (2) teoria da tensão interfacial e (3) teoria termodinâmica. A estrutura formada é influenciada pelas propriedades físico-químicas dos componentes utilizados e da razão entre os componentes. O objetivo desta revisão foi avaliar o estado da arte de sistemas microemulsionados enfatizando uma abordagem teórica. Além disso, os recentes avanços sobre a aplicabilidade clínca e utilização como carreador de moléculas insolúveis foram discutidas.


Microemulsions (ME) are thermodynamically stable and isotropic systems of two immiscible liquids (oil/water), stabilized by an interfacial film of surfactants, discovered by Hoar and Schulman in 1943. The study of ME formation is based on three areas of theory: (1) solubilization, (2) interfacial tension and (3) thermodynamics. ME structures are influenced by the physicochemical properties and proportions of their ingredients. The goal of this review is to assess the state of the art of microemulsified systems, from a theoretical viewpoint. Also, recent progress on their clinical application and use as carriers for insoluble compounds is discussed.


Subject(s)
Carrier Proteins , Emulsions/chemistry , Oils/chemistry
10.
São Paulo; s.n; 2009. 83 p. ilus, graf, tab.
Thesis in Portuguese | LILACS | ID: lil-553034

ABSTRACT

Os subprodutos do processamento de laranja representam sérios problemas de contaminação ao meio ambiente, mas estudos os apontam como alternativas promissoras, como ingredientes para a indústria alimentícia, devido ao seu elevado teor de fibra e pectina. Este trabalho teve o objetivo de estudar as propriedades funcionais da fibra obtida da polpa da laranja e sua aplicação em mortadelas de frango com baixo teor de gordura. A fibra da laranja foi obtida do processamento de suco concentrado, com granulomentrias de 1.322mµ (grossa), 786mµ (média) e 447 mµ (fina). O resultado da composição da fibra foi de 45,6% de fibra total, 26,8% de fibra insolúvel, 18,8% de fibra solúvel e 11,2% de pectina. Com relação às propriedades funcionais, a fibra "grossa" apresentou maior capacidade de reter água (p<0,05) às demais estudadas. A estabilidade da emulsão para as aplicações de 1, 2 e 3% de fibra apresentou resultado superior para a fibra "fina", não apresentando diferença significativa (p>0,05) da fibra de trigo, porém significativamente (p<0,05) superior ao controle (sem adição de fibras). Concentrações de 1,0 e 3,0% de fibra fina foram utilizadas para se obter mortadelas de frango com teor reduzido de gordura (4 e 16%), através do planejamento fatorial, sendo comparadas com uma formulação controle contendo 24% de gordura. No nível de 3% de fibra ocorreu aumento de valor b*, intensificando a cor amarela das mortadelas. A formulação (F3), com 1% de fibra e 4% de gordura, apresentou a melhor aceitação em todos os testes sensoriais realizados. A adição de fibras afetou significativamente (p<0,05) o resultado de gordura e o valor calórico. Os valores de pH, aw e estabilidade microbiológica mantiveram-se estáveis no período de estocagem (três meses sob refrigeração). Na microscopia, os produtos com fibra revelaram íntima associação entre fibra e glóbulos de gordura, resultando em emulsão cárnea estável, embora a reação com a fração protéica não esteja totalmente entendida...


Orange by-products from orange juice production represent deleterious and ecological problems to the environment. However reports have been pointed out a promising role as ingredients for food production by being relevant sources of fiber and pectin. This work aims to evaluate the fibers functional properties obtained from orange pulp and its application in a light emulsion poultry product as mortadella. The orange fiber was obtained from concentrated orange juice residue under different sizes of granulometry of 1322mµ (thick size) 786mµ (middle size) and 447 mµ (thin size). This residue presented a total fiber amount of 45.6% being insoluble fiber fraction of 26.8%, soluble fiber fraction of 18.8% and pectin fraction of 11.2%. In relation to functional properties, the thick fiber presented highest water holding capacity in comparison to the others. The emulsion stability (ES) by the use of 1.0, 2.0, and 3.0% of thin fiber presented superior result although not different in relation to wheat fiber and higher in relation to the control formulation without fiber (p<0.05). One to 3.0% of thin fiber concentrations were used to obtain poultry mortadella with reduced amount of fat, 4.0% and 16.0%, respectively, defined by a factorial planning statistic and comparing to the control formulation of 24.0% fat. Results showed that at the level of 3.0% there was an increase of b* value meaning the increase of mortadella yellow color. The formulation containing 1.0% fiber and 4.0% fat was the product most accepted by the panelists in every attribute evaluated. The fiber addition affected the final result of fat content and caloric value classifying the product as a light meat product. Moreover, values of pH and aw did not altered and microbiologically this product was stable (3 months of storage under refrigeration). Under microscopy, the fiber-meat product revealed an intimate association between the fiber and fat globule although a possibility of reacting to protein...


Subject(s)
Applied Research , Citrus sinensis , Food Handling , Dietary Fiber , Poultry Products , Birds , Emulsions/chemistry , Food Production , Food Technology
11.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 44(2): 249-259, abr.-jun. 2008. ilus, tab
Article in Portuguese | LILACS | ID: lil-488721

ABSTRACT

Os objetivos deste trabalho foram desenvolver e avaliar a estabilidade física de emulsões O/A contendo óleo de pequi (Caryocar brasiliense). Emulsões O/A contendo 10,0 por cento (p/p) de óleo de pequi foram preparadas e, para promover a estabilidade, a adição de carbomer, magnesium sulfate, sodium chloride e sorbitan oleate, foram estudadas. O tipo de emulsão foi verificado pelo método de diluição e o aspecto, homogeneidade e características organolépticas avaliadas através de análises macroscópicas. Como testes preliminares foram utilizados a centrifugação, ciclo gela-degela e o estresse térmico. Para avaliar a estabilidade acelerada as amostras foram submetidas em diferentes condições de estresse e analisadas a partir do valor de pH, análises macroscópicas e comportamento reológico. As emulsões preparadas com óleo de pequi, 0,3 por cento (p/p) de Acrylates/C10-30 Alkyl Acrilate Crosspolymer e 0,2 por cento (p/p) de carbomer apresentaram-se estáveis com propriedades pseudoplásticas e tixotrópicas. As características macroscópicas e valores obtidos de pH, viscosidade aparente, índices de fluxo e de consistência da área de histerese durante a estocagem indicaram estabilidade da formulação.


The aims of this study were to development and evaluated the physical stability of O/W emulsions containing "Pequi" oil (Caryocar brasiliense). O/W emulsions containing 10.0 percent (w/w) of Pequi oil were prepared, and to improve the stability, the carbomer, magnesium sulfate, sodium chloride and sorbitan oleate were added and studied. The direction of the emulsions was evaluated by dilution method and by macroscopic analysis, the appearance, homogeneity and organoleptic properties were evaluated. The centrifugation, freeze/defrost cycles and stress thermal were used to investigate the preliminary stability. To evaluate the accelerated stability, the samples were stored at different stress conditions and evaluated the pH value, macroscopic analysis and rheological behaviour. The O/W emulsions prepared with Pequi oil, 0.3 percent (w/w) of Acrylates/C10-30 Alkyl Acrilate Crosspolymer and 0.2 percent (w/w) of Carbomer have been found to be stables. These presented pseudoplastic flow behaviour and thixotropy. The macroscopic characteristics, the pH values and the values of the apparent viscosity, both consistency and flow index and hysteresis areas during aging indicated good long-term stability of this formulation.


Subject(s)
Cosmetic Stability , Cosmetics/analysis , Emulsions/chemistry , Rheology
12.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 41(3): 301-313, jul.-set.2005. ilus, tab
Article in Portuguese | LILACS | ID: lil-427926

ABSTRACT

A mistura de tensoativos com água, em determinadas proporções, na ausência ou na presença de substâncias lipofílicas pode formar diferentes tipos de agregados, entre os quais agregados polimorfos representados pelas microemulsões (ME) e mesofases liotrópicas - os cristais líquidos (LC), que estão intimamente ligados com a proporção e a natureza dos componentes da mistura. Nesse trabalho, foi discutido o papel desses sistemas na incorporação de fármacos com diferentes propriedades físico-químicas, influenciando fortemente a liberação, assim como a biodisponibilidade dos fármacos. Aspectos sobre a formação e a caracterização de microemulsões e cristais líquidos também foram discutidos. A análise da literatura indicou que, dependendo da polaridade do fármaco, o efeito da ME ou LC pode ser usado para otimizar o efeito terapêutico por meio do controle da velocidade ou do mecanismo de liberação do fármaco...


Subject(s)
Drug Compounding , Drug Stability , Emulsions/chemistry , Pharmacokinetics , Surface-Active Agents , Biological Availability , Microscopy, Polarization , Solubility
13.
Arch. latinoam. nutr ; 51(3): 265-268, sep. 2001.
Article in English | LILACS | ID: lil-333629

ABSTRACT

Arginine, as a basic amino acid, can alter the pH of a parenteral solution and consequently to interfere in the stability of other amino acids. The objective of this study was to analyze the chemical stability of amino acids in solutions for parenteral nutrition with arginine supplementation. Amino acids concentrations were determined using an amino acid analyzer in intervals of 12, 36, 72 hours, 7 and 28 days. Storage temperatures were -20 degrees C, 5 degrees C and 25 degrees C. A decrease was observed (p < 0.05) in the concentrations of threonine, methionine, isoleucine, leucine, proline and lysine on the 28th day of study, in the solutions kept at 25 degrees C. The side chains of threonine, methionine, isoleucine, leucine, proline and lysine have hydrophobic groups, which renders them less soluble in water when compared to amino acids that have polar side chains. The degradation of lysine was significant in the sample of parenteral nutrition supplemented with arginine, possibly due to the fact that the solution's pH was between 7.5 and 7.6, therefore facilitating the Maillard reaction between lysine and glucose.


Subject(s)
Amino Acids/chemistry , Dietary Supplements , Emulsions/chemistry , Maillard Reaction , Parenteral Nutrition , Amino Acids/administration & dosage , Arginine , Drug Stability , Maillard Reaction/drug effects
14.
RBM rev. bras. med ; 57(1/2): 75-78, jan.-fev. 2000. graf
Article in Portuguese | LILACS | ID: lil-319189

ABSTRACT

Difusäo de luz dinâmica (intensidade correlacionada à espectroscopia) é um método óptico de investigaçäo que permite obter uma medida rápida e detalhada do tamanhop médio e de toda distribuiçäo de partículascoloidais em suspensäo. Temos usado esta técnica para avaliar o tamanho médio e a multidifusäo das microemulsöes produzidas pela solubilizaçäo da preparaçöes farmacêuticas específicas baseadas na ciclosporina em um meio aquoso.(au)


Subject(s)
Emulsions/chemistry , Spectrophotometry , Cyclosporine
15.
Indian J Biochem Biophys ; 1991 Jun; 28(3): 174-83
Article in English | IMSEAR | ID: sea-27287

ABSTRACT

The results of formation, phase behaviour and physical properties of biological microemulsions prepared from saffola/AOT/hexylamine/water in presence of different additives, viz. cholesterol, crown ether, urea and brine, are presented. It has been found that the additives and temperature have striking effects; mono-, bi- and triphasic solutions interchanging proportions among themselves. The conduction of microemulsion at different [Water/AOT] ratios (w = 9,10,14,18,20,39 and 45) has shown conspicuous dependence on temperature with a significant degree of percolation, whereas the dependence of viscosity on temperature has shown normal declining trend with temperature. A maximum in viscosity with respect to its variation with amount of water has been observed. The Walden product (lambda eta) has evidenced noncompensation of ion transport by conduction with the viscosity of the medium. The activation energies evaluated for conduction (delta E*cond) and viscosity (delta E*vis) are systematic except at [Water/AOT] ratio, w = 20. The additives cholesterol, crown ether and their mixture have shown a decreasing effect on the delta E*cond for percolation, whereas delta E*vis has increased in their presence. The bicontinuous microemulsion has the prospect for use as liquid membrane.


Subject(s)
Aerosols , Amines , Calorimetry , Dioctyl Sulfosuccinic Acid , Emulsions/chemistry , Kinetics , Models, Biological , Safflower Oil , Surface-Active Agents , Water
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