Innovative Rice Seed Coating (Oryza Sativa) with Polymer Nanofibres and Microparticles Using the Electrospinning Method

Seed treatments are chemical or biological substances that are applied to seeds to control infection by disease-causing organisms, insects, or other pests. Seed treatment reduces production costs of seedlings, reduces the consumption of seeds, facilitates mechanization of sowing and improves the seedling establishment. The generation of nanofibres and microcapsules by the electrospinning technique is a novel approach for active ingredient controlled release. The study evaluates an innovative rice seed coating (Oryza sativa) with polymer nanofibres and microparticles using this method.Materials and Methods: Polymer nanofibres and microcapsules were applied by the electrospinning technique to irrigated rice seeds. The treatments consisted of: 1) Control, 2) Negative control - Polymer based microcapsule without fungicide. 3) Polymer based microcapsule with fungicide. Microbiological assays and germination tests were performed following the guidelines of the Seed Analysis Rules of the Ministry of Agriculture. Results: The applied polymer as a coating did not affect the physiological quality of the seeds, as attested by the result of the germination tests, and they proved to be effective in the control of fungi disease in crop seeds. Conclusion: The germination and phytosanitary characteristics were improved in the analyzed study

Polymers nanofibers as vehicles for the release of the synthetic sex pheromone of Grapholita molesta (Lepidoptera, Tortricidae)

The use of pheromones is a promising alternative in insect management and control. Recently, the incorporation and release of active ingredients from nanofibers has been of interest for agricultural purposes due to their higher surface area to volume ratios. The objective of this study was to produce nanofibers incorporating synthetic sex pheromones from the oriental fruit moth, Grapholita molesta (OFM), using different polymers. The nanofibers with pheromones were produced by electrospinning and were evaluated for: i) homogeneous distribution of OFM pheromone in nanofibers by electroantennography (EAG) tests; ii) dose-responses of OFM males to acetate cellulose nanofibers; iii) EAG responses of OFM males to different polymer nanofibers exposed under controled conditions for up to 5 weeks; iv) attractiveness of G. molesta to nanofibers containing synthetic OFM in field conditions; v) quantification of incorporated pheromone in PCL and PVAc nanofibers using gas chromatography and vi) morphology using scanning electron microscopy. The best field results were achieved in smoother fibers with higher impregnation. Pheromone incorporating nanofiber vehicles were tested that achieved the controlled release of the pheromone for up to three weeks in nanoscale and microscale. The polymer, solvent, and dosage incorporated in the nanofibers were important for controlled delivery. Understanding these factors is important for the development of better pheromone dispensers.El uso de feromonas es una alternativa promisora en el manejo y el control de plagas. Recientemente, la incorporación y eliminación de ingredientes activos de las nanofibras han despertado el interés para objetivos agrícolas debido a su elevada área en comparación a la superficie de proporción de volumen. El objetivo de este estudio fue producir nanofibras incorporando la feromona sexual sintética de la mariposa oriental Grapholita molesta (OFM) utilizando diferentes polímeros. Las nanofibras con feromona producidas por la técnica de electrohilado fueran evaluadas por: i) distribución homogénea de feromona de OFM en nanofibras por testes de electroantenografía (EAG); ii) dosis-respuestas de machos de OFM a nanofibras de acetato de celulosa; iii) respuestas EAG de machos de OFM a diferentes nanofibras de polímeros expuestos a condiciones controladas por hasta 5 semanas; iv) atracción de G. molesta a nanofibras conteniendo feromona sintética en condiciones de campo; v) cualificación de feromonas incorporadas de nanofibras de PCL y PVAc por cromatografía de gas y; vi) su morfología utilizando microscopio electrónico de exploración. Los mejores resultados de campo fueron conseguidos en fibras más blandas con mayor impregnación. Diferentes vehículos de nanofibras incorporando feromona fueron analizadas que consiguieron eliminación controlada de feromona hasta tres semanas, en nano y micro escalas. El polímero, solvente y dosis incorporadas en las nanofibras son importantes para la liberación controlada. Entender estos factores es importante para desarrollar mejores distribuidores de feromonas

Protective effect of guarana-loaded liposomes on hemolytic activity

Paullinia cupana var. sorbilis (Mart.) Ducke, popularly known as guarana, is one of the most promising plants in Brazilian flora and has attracted considerable interest from the scientific community owing to its numerous therapeutic activities and less side effects. Hence, using nanotechnology is a viable alternative to primarily improve the physicochemical characteristics and bioavailability of guarana. The objective of the present study was to develop, characterize, and evaluate the stability of liposomes containing guarana powder and to evaluate their antioxidant and hemolytic activity in vitro. Three different concentrations of guarana powder and two methods of liposome preparation were tested. Liposomes were developed and characterized, and their stability was analyzed by evaluating physicochemical parameters. Hemolytic activity of guarana liposomal formulation (G-Lip) was compared with that of guarana in its free form (FG) and of liposome without guarana (W-Lip). Red blood cells from rats were exposed to these different formulations dissolved in phosphate buffer solution (PBS; pH 7.4). The best stability was achieved for the formulation containing 1 mg.mL−1 guarana powder produced by the reverse phase evaporation method. FG showed dose-dependent antioxidant activity, which was maintained in G-Lip. W-Lip showed high hemolytic activity in PBS at pH 7.4 possibly because of the presence of polysorbate 80, and on addition of guarana to these structures, the hemolytic process was reversed. The same protective effect was observed for FG. It is believed that the complex structure of guarana, primarily the presence of polyphenols, exerts a powerful antioxidant action, helping to protect erythrocytes

AVALIAÇÃO DA ESTABILIDADE, LIBERAÇÃO E PERMEAÇÃO CUTÂNEA DE NANOCÁPSULAS CONTENDO BENZOFENONA-3

Made available in DSpace on 2018-06-27T18:56:34Z (GMT). No. of bitstreams: 2 Isabel Roggia.pdf: 2537332 bytes, checksum: de40e0aad80f6e3c3604e12b7f9fd9fa (MD5) Isabel Roggia.pdf.jpg: 3114 bytes, checksum: 8a3ab532420db5e246f4c91fd17d8d0c (MD5) Previous issue date: 2009-08-26Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe nanocosmetic products can contain nanostructured actives, presenting superior properties in relation to the conventional cosmetics, improving already existing formulations, increasing and its safety and effectiveness. Is this way, the sunscreens have been extensively investigated, due to its frequent and prolonged use. This work presents as main objective evaluate the in vitro release and skin permeation of the benzophenone-3 in polymeric nanoparticles, incorporated in different semi-solid formulations using, as membrane, cellulose acetate and abdominal human skin, respectively. This work also included physico-chemical stability studies, assessment of organoleptic characteristic, rheological assessment and determination of the term validity. The dosage technique of BZ3 in spectrophotometer was validated in all analyzed parameters and the results obtained met the specifications for linearity, precision, robustness and accuracy. The BZ3 concentration in the semi-solid formulations decreased for all formulations in the course of the experiment, both the nanoencapsulated BZ3 as in the free. The organoletptic characteristics and the pH were kept for all the formulations in study. The viscosity values did not altered for the formulations of hydrogel (HGNCBZ3) and gel cream (CGNCBZ3) containing encapsulated BZ3. The viscosity for hydrogel formulation containing BZ3 in the free form (HGBZ3) presented a significant increase. The spreading values remained stable for all the tested formulations, both for the nanoencapsulated active as in the free form. The formulations containing nanoencapsulated BZ3 presented greater term validity than formulations with BZ3 in the free form. Through studies of release was observed that the formulations containing BZ3 in the form encapsulated presented a lower release than free form. The formulations containing BZ3 in the free form, did not present a significant difference for the flow values in the different vehicles. It was still observed, that the BZ3 incorporated in the HGNCBZ3 presented a greater releasing flow, when compared with CGNCBZ3 and ESNCBZ3, showing that the vehicle may to influence in the behavior of the nanocarrier release. The skin permeation of the BZ3 incorporated in the gel cream was similar as much for the free form as encapsulated. The encapsulated BZ3 presented a greater concentration in the cornea extract. These results correspond to those found by Paese (2008) when the experiments were performed using pig s membrane, reaffirming the interchangeability between the membranes used for the permeation studies with nanoestrutured systens.Os produtos nanocosméticos podem veicular ativos nanoestruturados, apresentando propriedades superiores em relação aos cosméticos convencionais, proporcionando melhora das formulações já existentes, aumentando sua segurança e eficácia. Desta forma, os protetores solares têm sido extensivamente investigados, em função do uso frequente e prolongado dos mesmos. Este trabalho apresenta como objetivo principal avaliar a liberação e a permeação cutânea in vitro da benzofenona-3 (BZ3) em nanopartículas poliméricas, incorporadas em diferentes formulações semissólidas, usando como membrana acetato de celulose e pele abdominal humana, respectivamente. Este trabalho incluiu ainda estudos de estabilidade físico-química, avaliação das características organolépticas, avaliações reológicas e determinação do prazo de validade das formulações. A técnica de doseamento da BZ3 em espectrofotômetro foi validada em todos os parâmetros analisados e os resultados atenderam as especificações de linearidade, precisão, exatidão e robustez. A concentração de BZ3 nas formulações semissólidas diminuiu em todas as formulações no decorrer dos experimentos, tanto para o ativo incorporado na forma livre, como na forma nanoencapsulada. As características organolépticas e o pH foram mantidos para todas as formulações em estudo. Os valores de viscosidade não sofreram alterações para as formulações de hidrogel (HGNCBZ3) e creme gel (CGNCBZ3) contendo a benzofenona na forma nanoencapsulada. Para as formulações de hidrogel contendo BZ3 na forma livre (HGBZ3) houve um aumento significativo de viscosidade. Os valores de espalhabilidade mantiveram-se estáveis para todas as formulações testadas, tanto para o ativo na forma livre como nanoencapsulada. As formulações contendo a BZ3 nanoencapsulada apresentaram um prazo de validade maior do que as formulações com a BZ3 na forma livre. Através dos estudos de liberação, observou-se que as formulações contendo a BZ3 na forma nanoencapsulada apresentaram uma liberação menor em relação a sua forma livre. As formulações contendo a BZ3 na forma livre, não apresentaram diferença significativa para os valores de fluxo nos diferentes veículos. Foi observado ainda, que a BZ3 incorporada no HGNCBZ3 apresentou um fluxo de liberação maior, quando comparada com o CGNCBZ3 e a ESNCBZ3, demonstrando que o veículo pode influenciar o comportamento de liberação dos nanocarreadores. A permeação cutânea da BZ3 incorporada no creme gel foi semelhante tanto para forma livre como encapsulada. A BZ3 nanoencapsulada apresentou uma maior concentração no estrato córneo. Estes resultados correspondem aos encontrados por PAESE (2008), quando os experimentos foram realizados com membrana de porco, reafirmando a intercambialidade entre as membranas utilizadas para os estudos de permeação com sistemas nanoestruturados

DESENVOLVIMENTO, CARACTERIZAÇÃO E AVALIAÇÃO DA ESTABILIDADE E SEGURANÇA “IN VITRO” DE LIPOSSOMAS CONTENDO Paullinia cupana var. sorbilis (GUARANÁ)

Submitted by MARCIA ROVADOSCHI ([email protected]) on 2018-08-22T18:10:08Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_IsabelRoggia_parcial.pdf: 2275089 bytes, checksum: 85859128d6658714abfc7173f2587948 (MD5)Made available in DSpace on 2018-08-22T18:10:08Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_IsabelRoggia_parcial.pdf: 2275089 bytes, checksum: 85859128d6658714abfc7173f2587948 (MD5) Previous issue date: 2018-03-26The Paullinia cupana var. sorbilis, popularly known as guarana, is one of the most promising compounds in Brazilian flora. The presence of methylxanthines (caffeine, theophylline and theobromine) and tannins (caffeine and catechin) in its composition make it a potent therapeutic compound. Stimulant, antifungal, antimicrobial, antiparasitic activities, among others, are described in the literature as potentiality of this compound. On the other hand, when the product is exposed to high temperatures, in the presence of moisture, oxygen and in direct contact with light or, when stored in inadequate packaging, the integrity of the active ingredient may be impaired and consequently, the decrease and/or loss of activity and onset of toxicity can be observed. With the intent of obtaining a more stable, effective and safe product, the objective of this work was to prepare and characterize a liposomal system containing guarana powder and to evaluate its safety "in vitro" through a study of cytotoxicity and genotoxicity. First, analytical methods for the quantification of markers present in guarana were developed and validated by ultraviolet derivative (UVD), for caffeine and catechin, and by high performance liquid chromatography (HPLC), for quantification of caffeine, theophylline, theobromine, catechin and epicatechin in samples of guarana powder and liposomes. The methods developed proved to be linear, specific, precise, accurate and robust for the simultaneous determination of the different markers in the guarana powder sample and in the liposomes. Through the forced degradation study it can be observed, in general, a reduction of polyphenols content (catechin and epicatechin), compared to basic (0.1 M NaOH) and photolytic (fluorescence UVC) conditions, both for the standards and for guarana and for liposomes. For the latter, a reduction in the content of active compounds was also observed against oxidative conditions (3% H2O2). It is believed that this change is related to the process of epimerization and photostability, already described for polyphenols when in contact with basic and photolytic solutions, respectively. After conducting a preformulation study it was observed that liposomes containing 1 mg.mL-1 guarana powder, prepared by the reverse phase evaporation method and the ethanol injection method presented adequate characteristics and remained more stable in relation to the formulations containing 10 and 5 mg.ml-1. After the physical-chemical characterization and stability study of these formulations, the reverse phase evaporation method was chosen as the best method for encapsulation of guarana. These systems remained stable under 10 refrigeration without significantly modifying their characteristics for 60 days. A toxicological evaluation of liposomes in different cell cultures (3T3, HaCaT, A549, HepG2 and THP1) and in different concentrations (3.91-500 μg.mL-1) showed that, in general, the liposomes do not present significant toxicity up to a concentration of 125 μg.mL-1 when analyzed by the neutral red technique (NRU). By the (3-(4,5- Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) technique (MTT), the viability reduction was observed from the concentration of 31.25 μg.mL-1 for the 3T3 and HepG2 cells and 62.5 μg.mL-1 for the A549 cell. Hemolysis, photohaemolysis, and hemoglobin oxidation tests showed that the liposomes, in the absence of guarana, caused damage to the eritrocytes and that guarana can reverse and/or protect the cells against this damage. It was also observed that this damage is possibly related to the presence of polysorbate 80 present in the formulations. When chlorpromazine was added to the experiments, it was observed that the guarana containing liposomes were able to protect the cells from the damage caused by that compound. Through the genotoxicity study it was possible to observe that guarana and liposomes did not cause DNA damage. The evaluation of the antioxidant activity by the DPPH technique proved the antioxidant effect, already described for guarana and, it was verified that this activity was maintained after the incorporation of guarana in the liposomes. This activity observed for all treatments was dose dependent of the concentration of guarana in the formulation. In this way, we can conclude that it was possible to develop a liposome system through the reverse phase evaporation method containing 1 mg.mL-1 of guarana powder, remaining stable for 60 days and showing safety against the different cell types tested. It is also worth noting the importance of new experiments, mainly the performance of the spray drying to improve the stability of the active ingredients and the characterization of these new systems formed, as well as additional tests regarding the safety profile.A Paullinia cupana var. sorbilis, popularmente conhecida por guaraná é um dos compostos mais promissores da flora brasileira. A presença de metilxantinas (cafeína, teofilina e teobromina) e taninos (cafeína e catequina) em sua composição, fazem deste, um potente composto terapêutico. Atividades estimulante, antifúngica, antimicrobiana, antiparasitária, dentre outras, estão descritas na literatura como potencialidade deste composto. Em contra partida, quando o produto encontra-se exposto a temperaturas elevadas, na presença de umidade, oxigênio e em contato direto com a luz ou ainda, quando conservado em embalagens inadequadas, a integridade dos ativos pode ser prejudicada e consequentemente a diminuição e/ou perda da atividade e surgimento de toxicidade podem ser observadas. Com a proposta de obter um produto mais estável, eficaz e seguro, o objetivo deste trabalho foi preparar e caracterizar um sistema lipossomal contendo pó de guaraná, além de avaliar a sua segurança “in vitro” através de estudo de citotoxicidade e genotoxicidade. Primeiramente, métodos analíticos para quantificação dos marcadores presentes no guaraná foram desenvolvidos e validados por espectrofotometria ultravioleta derivada (UVD), para a cafeína e a catequina e por cromatografia líquida de alta eficiência (CLAE) para quantificação de cafeína, teofilina, teobromina, catequina e epicatequina em amostras de pó de guaraná e nos lipossomas. Os métodos desenvolvidos demostraram-se lineares, específicos, precisos, exatos e robustos para determinação simultânea dos diferentes marcadores em amostra de pó de guaraná e nos lipossomas. Através do estudo de degradação forçada pode-se observar, de forma geral, redução no teor dos polifenóis (catequina e epicatequina), frente a condições básicas (NaOH 0,1 M) e fotolíticas (UVC fluorescentes), tanto para os padrões, como para o guaraná e para os lipossomas. Para esse último, observou-se também redução no teor dos compostos ativo frente a condições oxidativas (H2O2 3%). Acredita-se que essa alteração esteja relacionada ao processo de epimerização e fotoinstabilidade, já descrito para os polifenóis quando em contato com soluções básicas e fotolíticas, respectivamente. Após a realização de um estudo de pré-formulação observou-se que os lipossomas contendo 1 mg/mL de pó de guaraná, preparados pelo método de evaporação em fase reversa e pelo método de injeção de etanol apresentaram características adequadas e mantiveram-se mais estáveis em relação as formulações contendo 10 e 5 mg/mL. Posteriormente a caracterização físico-química e o estudo de estabilidade destas formulações, o método de evaporação em fase reversa foi escolhido 8 como o melhor método para encapsulação do guaraná. Esses sistemas mantiveram-se estáveis sobre refrigeração, sem modificar de forma significativa, das suas características por 60 dias. A avaliação toxicológica dos lipossomas frente á diferentes culturas celulares (3T3, HaCaT, A549, HepG2 e THP1) em diferentes concentrações (3,91 – 500 μg/mL), mostrou que, de forma geral, os lipossomas não apresentam toxicidade significativa até a concentração de 125 μg/mL quando analisados pela técnica de vermelho neutro (NRU). Já pela técnica de brometo de 3-(4,5-dimetil-2- tiazolil)-2, 5-difenil-2H-tetrazólio (MTT) a redução da viabilidade foi observada a partir da concentração de 31,25 μg/mL para as células 3T3 e HepG2 e 62,5 μg/mL para a célula A549. Os testes de hemólise, fotohemólise e oxidação da hemoglobina mostraram que os lipossomas sem a presença do guaraná apresentaram dano aos eritrócitos e que o guaraná consegue reverter e/ou proteger as células contra esse dano. Observou-se também que esse dano, possivelmente esteja relacionado à presença do polissorbato 80 presente nas formulações. Quando foi adicionado a clorpromazina aos experimentos, observou-se que os lipossomas contendo guaraná conseguiram proteger as células do dado provocado por esse composto. Pelo estudo de genotoxicidade foi possível observar que o guaraná e os lipossomas contendo guaraná não ocasionaram dano ao DNA. A avaliação da atividade antioxidante pela técnica de DPPH comprovou o efeito antioxidante, já descrito para o guaraná, e ainda, verificou-se que essa atividade foi mantida após a incorporação do guaraná nos lipossomas. Essa atividade observada para todos os tratamentos foi dose dependente da concentração de guaraná na formulação. Desta forma, podemos concluir que foi possível desenvolver um sistema lipossomal através do método de evaporação em fase reversa contendo 1 mg/mL de pó de guaraná, mantendo-se estável por 60 dias e mostrando-se seguro frente os diferentes tipos celulares testados. Resalta-se ainda, a importância de novos experimentos, principalmente a realização da secagem por aspersão para melhorar a estabilidade dos ativos e a caracterização destes novos sistemas formados, além de testes adicionais quanto ao perfil de segurança

Polymers nanofibers as vehicles for the release of the synthetic sex pheromone of Grapholita molesta (Lepidoptera, Tortricidae)

The use of pheromones is a promising alternative in insect management and control. Recently, the incorporation and release of active ingredients from nanofibers has been of interest for agricultural purposes due to their higher surface area to volume ratios. The objective of this study was to produce nanofibers incorporating synthetic sex pheromones from the oriental fruit moth, Grapholita molesta (OFM), using different polymers. The nanofibers with pheromones were produced by electrospinning and were evaluated for: i) homogeneous distribution of OFM pheromone in nanofibers by electroantennography (EAG) tests; ii) dose-responses of OFM males to acetate cellulose nanofibers; iii) EAG responses of OFM males to different polymer nanofibers exposed under controled conditions for up to 5 weeks; iv) attractiveness of G. molesta to nanofibers containing synthetic OFM in field conditions; v) quantification of incorporated pheromone in PCL and PVAc nanofibers using gas chromatography and vi) morphology using scanning electron microscopy. The best field results were achieved in smoother fibers with higher impregnation. Pheromone incorporating nanofiber vehicles were tested that achieved the controlled release of the pheromone for up to three weeks in nanoscale and microscale. The polymer, solvent, and dosage incorporated in the nanofibers were important for controlled delivery. Understanding these factors is important for the development of better pheromone dispensers.El uso de feromonas es una alternativa promisora en el manejo y el control de plagas. Recientemente, la incorporación y eliminación de ingredientes activos de las nanofibras han despertado el interés para objetivos agrícolas debido a su elevada área en comparación a la superficie de proporción de volumen. El objetivo de este estudio fue producir nanofibras incorporando la feromona sexual sintética de la mariposa oriental Grapholita molesta (OFM) utilizando diferentes polímeros. Las nanofibras con feromona producidas por la técnica de electrohilado fueran evaluadas por: i) distribución homogénea de feromona de OFM en nanofibras por testes de electroantenografía (EAG); ii) dosis-respuestas de machos de OFM a nanofibras de acetato de celulosa; iii) respuestas EAG de machos de OFM a diferentes nanofibras de polímeros expuestos a condiciones controladas por hasta 5 semanas; iv) atracción de G. molesta a nanofibras conteniendo feromona sintética en condiciones de campo; v) cualificación de feromonas incorporadas de nanofibras de PCL y PVAc por cromatografía de gas y; vi) su morfología utilizando microscopio electrónico de exploración. Los mejores resultados de campo fueron conseguidos en fibras más blandas con mayor impregnación. Diferentes vehículos de nanofibras incorporando feromona fueron analizadas que consiguieron eliminación controlada de feromona hasta tres semanas, en nano y micro escalas. El polímero, solvente y dosis incorporadas en las nanofibras son importantes para la liberación controlada. Entender estos factores es importante para desarrollar mejores distribuidores de feromonas

Vitamin C as a shelf-life extender in liposomes

The objective of this study was to evaluate the influence of vitamin C (VC) on the stability of stored liposomes under different climatic conditions. Liposomal formulations containing 1 mg/mL of VC (LIP-VC) and blank formulations (LIP-B) were prepared by the reverse-phase evaporation method. After preparation, they were characterized according to their refractive index, average vesicle diameter, polydispersity index (PDI), zeta potential, pH, content, encapsulation efficiency (EE%), morphology, stability and antioxidant activity. For stability, LIP-VC and LIP-B were stored in different climatic conditions (4 °C, 25 °C and 40 °C) for 30 days. The LIP-VC presented 1.3365 refractive index, 161 nm of mean diameter, 0.231 PDI, -7.3 mV zeta potential, 3.2 pH, 19.4% EE%, spherical morphology, 1 mg/mL of VC content, and antioxidant activity of 12 and 11.4 μmol of TE/mL for the radical DPPH and ABTS+, respectively. During stability, the LIP-B stored in 40 °C showed an instability in the parameters: PDI, vesicle size and zeta potential after 15 days, while the LIP-VC remained stable in its size and PDI for 30 days. After that, it is shown that VC can be used as an antioxidant and stabilizer in liposomes to increase the stability and shelf-life of vesicles

Profiling and Evaluation of the Effect of Guarana-Loaded Liposomes on Different Skin Cell Lines: An In Vitro Study

The objective of this study was to analyze the in vitro stability and toxicity of liposomes containing guarana in skin cell lines. The liposomes were produced by the reverse phase evaporation method containing 1 mg/mL guarana. The stability of the liposomes was evaluated by physical-chemical parameters for up to 90 days using three different storage conditions. The cytotoxicity of guarana (GL), liposomes (B-Lip), and guarana-loaded liposomes (G-Lip) was evaluated on spontaneously immortalized human keratinocyte cell lines (HaCaT), murine Swiss albino fibroblasts (3T3), and human fibroblasts (1BR.3.G). The evaluation was performed using cellular viability analysis. The techniques used were 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red capturing (NRU), and the analyses were conducted after 24, 48, and 72 h of exposure of these cells to the different treatments. The G-Lip exhibited physical-chemical stability for 60 days when the samples were stored in a refrigerator. The GL, B-Lip, and G-Lip demonstrated low cytotoxicity in the three different cell cultures tested since a small reduction in cell viability was only observed at the highest concentrations. In addition, greater cell damage was observed for B-Lip; however, guarana protected the cells from this damage. Thus, G-Lip structures can be considered promising systems for topical applications

Validação de metodologia analítica para a determinação de benzofenona-3 nanoencapsulada incorporada em creme gel e estudo da estabilidade físico química

Este trabalho teve como objetivos validar a metodologia analítica para a quantificação de benzofenona-3 (BZ3) por espectrofotometria na região do ultravioleta, realizar estudo de estabilidade e determinar o prazo de validade deste ativo nanoencapsulado e incorporado em um creme gel. O método validado apresentou-se seletivo, linear na faixa de 2 - 20 µg/mL, com coeficiente de correlação (R2=0,999993), preciso (DPR < 2,44%), exato (98,8% - 100,3%) e robusto, podendo ser utilizado na quantificação de BZ3 nanoencapsulada em creme gel. Os cremes géis, contendo BZ3 nanoencapsulada e livre não tiveram alterações significativas com relação à aparência, cor, odor, pH, viscosidade e espalhabilidade, durante 180 dias, expostos a temperatura e umidade controlada de 40 ºC e 75% UR. Em ambas as formulações o teor de BZ3 diminuiu, porém, quando na forma livre, o ativo degradou mais rapidamente (30 dias) do que para a forma nanoencapsulada (150 dias), o que nos permite concluir que as nanocápsulas desempenharam um papel de proteção para o ativo. Para o creme gel contendo as nanocápsulas de BZ3 o prazo estimado de validade foi de 125 dias, e para o que continha a BZ3 livre de 69 dias