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1.
Heliyon ; 6(5): e03831, 2020 May.
Article in English | MEDLINE | ID: mdl-32395645

ABSTRACT

Sunscreens have been employed on daily skin care for centuries. Their role in protecting the skin from sun damage, avoiding accelerated photoaging and even limiting the risk of development of skin cancer is unquestionable. Although several chemical and physical filters are approved as sunscreens for human use, their safety profile is dependent on their concentration in the formulation which governs their acceptance by the regulatory agencies. A strategic delivery of such molecules should provide a UV protection and limit the skin penetration. Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) may offer an alternative approach to achieve a synergistic effect on the UV protection when loaded with sunscreens as particles themselves also have a UV light scattering effect. Besides, the lipid character of SLN and NLC improves the encapsulation of lipophilic compounds, with enhanced loading capacity. Silica nanoparticles have also been employed in sunscreen formulations. Due to the formed sol-gel complexes, which covalently entrap sunscreen molecules, a controlled release is also achieved. In the present work, we have developed a new sunscreen formulation composed of hybrid SLN-Silica particles loaded with octyl methoxycinnamate (Parsol®MCX), and their further incorporation into a hydrogel for skin administration. Hybrid SLN-silica particles of 210.0 ± 3.341 nm of mean size, polydispersity below 0.3, zeta potential of ca. |7| mV, loading capacity of 19.9% and encapsulation efficiency of 98.3% have been produced. Despite the slight negative surface charge, the developed hybrid nanoparticles remained physicochemically stable over the study period. Turbiscan transmission profiles confirmed the colloidal stability of the formulations under stress conditions. The texture profile analysis of Parsol-SLN and Parsol-SLN-Si revealed semi-solid properties (e.g. adhesiveness, hardness, cohesiveness, springiness, gumminess, chewiness, resilience) suitable for topical application, together with the bioadhesiveness in the skin of pig ears. The non-irritation profile of the hybrid nanoparticles before and after dispersion into Carbopol hydrogels was confirmed by HET-CAM test.

2.
Rev. ciênc. farm. básica apl ; 28(1): 85-92, 2007. tab, graf
Article in Portuguese | LILACS | ID: lil-485205

ABSTRACT

As propriedades físico-químicas dos excipientes podem predominar nas características físicas do sistema sólido particulado e influenciar decisivamente o comportamento de compactação, já que, muitas vezes, estes se apresentam em proporções muito maiores que o fármaco nas formulações de comprimidos. O objetivo deste trabalho foi avaliar a influência do tamanho degranulados de lactose nas características físicas decomprimidos obtidos em diferentes diâmetros de punção, uma vez que tal relação não tem sido exploradana literatura. Granulados de diferentes tamanhos foram produzidos por via úmida e compactados em punções de diferentes diâmetros por aplicação de diferentes forças. Avaliou-se distribuição granulométrica, densidade aparente e fluxo dos granulados e características físicas dos comprimidos (peso, dureza, friabilidade e tempo de desintegração). Os resultados indicam que para os comprimidos produzidos em punções de 7mm de diâmetro, situação em que há predomínio das características do excipiente em razão da baixa dose do fármaco, a seleção do tamanho dos grânulos torna-se fundamental para a resistência mecânica do compacto. Por outro lado, foi possível obter comprimidos de maiores dimensões, punções 9, 11 e 13mm, a partir de grânulos de todos os tamanhos estudados.


The compaction behavior of powdered solids used in tablets can be dominated by the physical-chemical properties of the excipients because, frequently, they are present in much larger amounts than the drug in tablet formulation. The aim of this study was to evaluate theinfluence of the size of lactose granules on the physical characteristics of tablets produced in punches of various diameters, since this relation has not been explored in the literature. Granules were produced in several sizes by wet granulation and compressed in punches of different diameters by applying different forces. Size distribution, apparent density and flow of granules were evaluated, as well as the physical characteristics of the tablets (weight, friability, hardness and disintegration time). The results indicate that in situations where excipient characteristics predominate due to low drug content, as in the 7 mm punch, the selection of granule size is important for the mechanical strength of tablet. On the other hand, with the 9, 11 and 13mm punches, it was possible to produce strong tablet from all sizes of granules.


Subject(s)
Tablets/chemistry , Lactose/pharmacology , Drug Compounding
3.
Rev. ciênc. farm. básica apl ; 28(2): 209-214, 2007. tab
Article in Portuguese | LILACS | ID: lil-486512

ABSTRACT

A esquistossomose mansônica é causada pelo trematódeo digenético intravascular Schistosoma mansoni. Para o tratamento dessa enfermidade o praziquantel (PZQ) e a oxamniquina (OXA) são os fármacos escolhidos. Noentanto, esses fármacos apresentam limitações quanto à ação e casos de resistência ou tolerância já foram relatados. Por esse motivo, são necessários os estudos de novas alternativas que visam melhorar os fármacos já existentes, como a incorporação desses em lipossomas. Este estudo verificou a ação do praziquantel incorporado a lipossomas (lip.PZQ) sobre os ovos de S. mansoni, linhagem BH em camundongos Mus musculus (Swiss-SPF). Para tanto, foram testadas quatro doses de PZQ elip.PZQ (47; 60; 250 e 300mg/kg) sendo que parte dos camundongos foi tratada após 30 dias de infecção e outra após 45 dias. A análise do o ograma mostrou que a dose lip.PZQ 300mg/kg administrada no 45º dia de infecção foi mais eficaz, pois reduziu a oviposição pelas fêmeas de S. mansoni.


Subject(s)
Animals , Mice , Anthelmintics/therapeutic use , Antigens, Helminth/pharmacology , Praziquantel/pharmacology , Schistosoma mansoni , Liposomes
4.
Drug Dev Ind Pharm ; 32(2): 229-38, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16537203

ABSTRACT

Gelatin microparticles containing propolis ethanolic extractive solution were prepared by spray-drying technique. Particles with regular morphology, mean diameter ranging of 2.27 microm to 2.48 microm, and good entrapment efficiency for propolis were obtained. The in vitro antimicrobial activity of microparticles was evaluated against microorganisms of oral importance (Enterococcus faecalis, Streptococcus salivarius, Streptococcus sanguinis, Streptococcus mitis, Streptococcus mutans, Streptococcus sobrinus, Candida albicans, and Lactobacillus casei). The utilized techniques were diffusion in agar and determination of minimum inhibitory concentration. The choice of the method to evaluate the antimicrobial activity of microparticles showed be very important. The microparticles displayed activity against all tested strains of similar way to the propolis, showing greater activity against the strains of E. salivarius, S. sanguinis, S. mitis, and C. albicans.


Subject(s)
Anti-Infective Agents/administration & dosage , Anti-Infective Agents/therapeutic use , Gelatin/chemistry , Propolis/administration & dosage , Propolis/therapeutic use , Candida albicans/drug effects , Drug Carriers , Ethanol/chemistry , Lacticaseibacillus casei/drug effects , Microbial Sensitivity Tests , Particle Size , Streptococcaceae/drug effects
5.
Rev. ciênc. farm ; 25(2): 79-84, 2004. ilus
Article in English | LILACS | ID: lil-418895

ABSTRACT

The purpose of this study was to investigative the in vitro release of propolis from gelatin microparticles. Gelatin microparticles containing porpolis extractive solution (PES) were prepared by spray-drying technique. Microparticles with a mean diameter of 2.50 µm and with regular morphology were obtained. The entrapment efficiency of propolis in the microparticles was over 39%. Spray-drying showed to be a feasible method for the preparation of gelatin microparticles containing propolis. Comparing to PES, the in vitro release of propolis from gelatin microparticles in aqueous medium was slower, considering markes 1 and 2. Thus, it was possible to transform a liquid propolis dosage form into a solid one, improving manipulation, packaging and storage and with modified release in aqueous medium, comparatively to the ethanolic extract of the drug


Subject(s)
Drug Compounding/methods , Gelatin , In Vitro Techniques , Propolis
6.
Rev. ciênc. farm ; 25(1): 65-68, 2004.
Article in Portuguese | LILACS | ID: lil-418916

ABSTRACT

Este artigo expressa uma preocupação com o ensino farmacêutico baseado nas novas diretrizes curriculares do Conselho Nacional de Ensino. O passado recente priorizou a formação de recursos humanos para as modalidades em detrimento da área privativa do Farmacêutico, a Farmácia em toda sua abrangência. Para não incorrermos no mesmo erro, é necessário desenvolver competências, que possibilitem ao egresso aplicar o conhecimento técnico-científico no contexto social. As novas diretrizes curriculares encerram o ciclo no qual a formação profissional aparecia com o marco divisório das modalidades análises clínicas e indústria. Modelo no qual se concebia a possibilidade de assistência farmacêutica sem conhecimento integral do medicamento não pode ser repetido por uma formação superficialista, segmentada, repleta de atividades técnicas previsíveis e repetitivas e, sobretudo, se conduzido por pessoas sem o preparo necessário ao ensino da atividade. O retorno às atividades primárias do Farmacêutico deve ser precedido pela formação de recursos humanos específicos para a área, o que não acontecerá a longo prazo


Subject(s)
Humans , Education, Pharmacy/trends
7.
Int J Pharm ; 264(1-2): 45-55, 2003 Oct 02.
Article in English | MEDLINE | ID: mdl-12972335

ABSTRACT

Gelatin microparticles containing propolis extractive solution (PES) were prepared by spray-drying technique. The optimization of the spray-drying operating conditions and the proportions of gelatin and mannitol were investigated. Regular particle morphology was obtained when mannitol was used, whereas mannitol absence produced a substantial number of coalesced and agglomerated microparticles. Microparticles had a mean diameter of 2.70 microm without mannitol and 2.50 microm with mannitol. The entrapment efficiency for propolis of the microparticles was upto 41% without mannitol and 39% with mannitol. The microencapsulation by spray-drying technique maintained the activity of propolis against Staphylococcus aureus. These gelatin microparticles containing propolis would be useful for developing intermediary or eventual propolis dosage form without the PES' strong and unpleasant taste, aromatic odour, and presence of ethanol.


Subject(s)
Gelatin/chemistry , Propolis/chemistry , Chromatography, High Pressure Liquid , Drug Carriers , Drug Compounding , Mannitol , Microscopy, Electron, Scanning , Particle Size , Propolis/pharmacology , Staphylococcus aureus/drug effects
8.
Braz. j. med. biol. res ; 29(4): 489-94, Apr. 1996. graf
Article in English | LILACS | ID: lil-163891

ABSTRACT

Anticardiolipin antibodies from sera of patients with systemic lupus erythematosus or syphilis induced leakage of entrapped carboxyfluorescein (CF) from cardiolipin (CL)/phosphatidylcholine(PC) vesicles prepared by sonication of equimolar mixtures of CL:PC. The sera dilution used here was 1:7500. IgG (5-20 mug/ml) from the same sera, not containing beta2GPI, also produced a concentration-dependent leak. Vesicle leakage was inhibited by salt and was not detected with vesicles prepared exclusively with phosphatidylcholine. The demonstration of antibody-induced vesicle leakage offers a convenient system to investigate the mechanism of antibody-lipid binding as well as a potential diagnostic tool.


Subject(s)
Humans , Antibodies, Anticardiolipin/therapeutic use , Cardiolipins/immunology , Syphilis/immunology , Lupus Erythematosus, Systemic/blood , Syphilis/diagnosis
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