Determinant factors affecting the efficacy of sunscreens

Existem diversas formas para se obter o máximo de proteção de um filtro solar. Cuidados simples durante a formulação e o desenvolvimento de novas técnicas de preparação permitem a obtenção de um produto de qualidade, com utilização facilitada e altos valores de FPS. A aplicação do filtro solar e a conscientização das pessoas determinam o nível de proteção atingido. Conhecendo-se a possibilidade de se obter produtos de qualidade que oferecem alta proteção e que os hábitos das pessoas também contribuem na fotoproteção, discute-se, neste artigo, sobre os métodos para aumentar a fotoproteção, que se iniciam no laboratório e terminam no momento do uso, e sobre a necessidade da existência de fotoprotetores com valores de FPS muito elevados.There are several different ways to obtain the maximum protection from a sunscreen. Simple care in the preparation and development of new techniques lead to an adequate product which presents easy use and high SPF. The way the product is applied as well as the people knowledge determines the level of protection achieved. This paper focuses on methods to increase the photoprotection which start with the development of the product and end up in the moment of their application

Determinant factors affecting the efficacy of sunscreens

Existem diversas formas para se obter o máximo de proteção de um filtro solar. Cuidados simples durante a formulação e o desenvolvimento de novas técnicas de preparação permitem a obtenção de um produto de qualidade, com utilização facilitada e altos valores de FPS. A aplicação do filtro solar e a conscientização das pessoas determinam o nível de proteção atingido. Conhecendo-se a possibilidade de se obter produtos de qualidade que oferecem alta proteção e que os hábitos das pessoas também contribuem na fotoproteção, discute-se, neste artigo, sobre os métodos para aumentar a fotoproteção, que se iniciam no laboratório e terminam no momento do uso, e sobre a necessidade da existência de fotoprotetores com valores de FPS muito elevados.There are several different ways to obtain the maximum protection from a sunscreen. Simple care in the preparation and development of new techniques lead to an adequate product which presents easy use and high SPF. The way the product is applied as well as the people knowledge determines the level of protection achieved. This paper focuses on methods to increase the photoprotection which start with the development of the product and end up in the moment of their application

Validation of a spectrophotometric method to estimate the adsorption on nanoemulsions of an antimalarial oligonucleotide

This study describes the validation of a spectrophotometric method to estimate oligonucleotides association with cationic nanoemulsions. Phosphodiester and phosphorothioate oligonucleotides targeting Plasmodium falciparum topoisomerase II were analyzed at 262 nm. Linear response (r > 0.998) was observed from 0.4 to 1.0 nmol/mL, the relative standard deviation values for the intra- and inter-days precision were lower than 2.6% and the recovery ranged from 98.8 to 103.6% for both oligonucleotides. The association efficiency was estimated based on an ultrafiltration/centrifugation method. Oligonucleotides recovery through 30 kDa-membranes was higher than 92%. The extent of oligonucleotides association (42 to 98%) varied with the composition of nanoemulsion

NanotoxicologyMaterials, Methodologies, and Assessments /

XV, 411 p. 42 illus., 22 illus. in color.online r

The Potential of Nanotechnology in Medically Assisted Reproduction

Reproductive medicine is a field of science which searches for new alternatives not only to help couples achieve pregnancy and preserve fertility, but also to diagnose and treat diseases which can impair the normal operation of the reproductive tract. Assisted reproductive technology (ART) is a set of methodologies applied to cases related to infertility. Despite being highly practiced worldwide, ART presents some challenges, which still require special attention. Nanotechnology, as a tool for reproductive medicine, has been considered to help overcome some of those impairments. Over recent years, nanotechnology approaches applied to reproductive medicine have provided strategies to improve diagnosis and increase specificity and sensitivity. For in vitro embryo production, studies in non-human models have been used to deliver molecules to gametes and embryos. The exploration of nanotechnology for ART would bring great advances. In this way, experiments in non-human models to test the development and safety of new protocols using nanomaterials are very important for informing potential future employment in humans. This paper presents recent developments in nanotechnology regarding impairments still faced by ART: ovary stimulation, multiple pregnancy, and genetic disorders. New perspectives for further use of nanotechnology in reproductive medicine studies are also discussed

Hemocompatibility of poly(epsilon-caprolactone) lipid-core nanocapsules stabilized with polysorbate 80-lecithin and uncoated or coated with chitosan

The hemocompatibility of nanoparticles is of critical importance for their systemic administration as drug delivery systems. Formulations of lipid-core nanocapsules, stabilized with polysorbate 80-lecithin and uncoated or coated with chitosan (LNC and LNC-CS), were prepared and characterized by laser diffraction (D[4,3]: 129 and 134 nm), dynamic light scattering (119 nm and 133 nm), nanoparticle tracking (D50: 124 and 139 nm) and particle mobility (zeta potential: -15.1 mV and + 9.3 mV) analysis. In vitro hemocompatibility studies were carried out with mixtures of nanocapsule suspensions in human blood at 2% and 10% (v/v). The prothrombin time showed no significant change independently of the nanocapsule surface potential or its concentration in plasma. Regarding the activated partial thromboplastin time, both suspensions at 2% (v/v) in plasma did not influence the clotting time. Even though suspensions at 10% (v/v) in plasma decreased the clotting times (p < 0.05), the values were within the normal range. The ability of plasma to activate the coagulation system was maintained after the addition of the formulations. Suspensions at 2% (v/v) in blood showed no significant hemolysis or platelet aggregation. In conclusion, the lipid-core nanocapsules uncoated or coated with chitosan are hemocompatible representing a potential innovative nanotechnological formulation for intravenous administration. (C) 2012 Elsevier B. V. All rights reserved.CAPES (Brazil)CAPES/BrazilFAPERGS (PqG)FAPERGS (PqG)CNPq/FAPERGS (PRONEX and PRONEM)CNPq/FAPERGS (PRONEX and PRONEM)INCT-IF/CNPqINCT_if (CNPq)Rede Nanobiotecnologia CAPESRede Nanobiotecnologia CAPESCNPq (Brasilia, Brazil)CNPq/Brasilia/Brazi

Obtenção e avaliação de forma farmacêutica contendo óleo essencial de Cymbopogon citratus

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