INFLUÊNCIA DA VISCOSIDADE DO VEÍCULO NA LIBERAÇÃO IN VITRO DA CAFEÍNA

A reologia é um parâmetro importante para avaliação do comportamento de fluxo do material, determinando como este flui ou deforma, sob influências externas. Seu estudo abrange a viscosidade, tipo de fluxo, valor de rendimento e tixotropia do produto. Viscosidade é uma expressão de resistência do fluido ao fluxo: quanto maior a viscosidade, maior a resistência. O objetivo deste trabalho foi verificar, no período de um mês, a viscosidade de dois géis acrescidos de cafeína, ativo empregado em produtos cosméticos, correlacionando viscosidade x liberação in vitro da substância ativa. Foram preparadas duas formulações de gel, as quais se diferenciaram apenas pela concentração do polímero hidrofílico Carbopol 940® (1 e 1,5%). Além do polímero, as formulações apresentaram propilenoglicol, álcool etílico, fenoxietanol e parabenos, tampão acetato de sódio 0,1 M e trietanolamina. Para o estudo da viscosidade, utilizou-se o viscosímetro rotativo Visco Star-LP Select. Já para os estudos de liberação empregou-se célula de difusão, contendo dois compartimentos separados por uma membrana de diálise. No compartimento doador, aplicou-se as formulações objeto de estudo enquanto que o compartimento receptor foi composto de tampão acetato (solução receptora). Em tempos pré-determinados (1, 30, 60, 90, 120 e 150 minutos), amostras da solução receptora foram coletadas e analisadas em espectrofotômetro para determinação da concentração de cafeína liberada. Para ambos os géis, em todos os dias analisados, os resultados do perfil reológico evidenciaram fluxo não newtoniano, do tipo pseudoplástico tempo independente. Através da análise de variância, verificou-se que a viscosidade do gel interferiu de maneira significativa na liberação da cafeína pelo veículo. Além disso, comprovou-se que o aumento da viscosidade, em função do aumento da concentração de Carbopol 940®, diminuiu a velocidade de liberação da cafeína, podendo este excipiente ser determinante para a produção de uma formulação de "liberação imediata" ou "liberação controlada". 10.5216/ref.v4i1.212

Sustainability, natural and organic cosmetics: consumer, products, efficacy, toxicological and regulatory considerations

The interest in sustainable products has increased along the years, since the choice of products, packaging and production processes have a great impact on the environment. These products are classified by regulatory agencies in different categories, aggregating advantages to the product and increasing the demand by consumers. However, there is no harmonization in guidelines of these certifying agencies and each cosmetic industry formulates their product and packaging in a more rational way, which causes less damage to the environment. Many cosmetic products have in their formulation natural products that perform a specific biological function, but these products should be evaluated on efficacy and toxicological aspects. The aim of this article is to approach sustainability, natural and organic cosmetics, considering the consumer and the efficacy, toxicological and regulatory aspects.O interesse por produtos sustentáveis tem aumentado ao longo dos anos, desde a escolha dos produtos, embalagens e processos de produção tendo um grande impacto sobre o meio ambiente. Estes produtos são classificados por agências reguladoras em diferentes categorias, agregando vantagens ao produto e aumentando a demanda por parte dos consumidores. No entanto, não existe uma harmonização nas diretrizes destes órgãos de certificação e cada indústria cosmética formula seu produto e embalagem de uma forma mais racional, levando a menos danos ao meio ambiente. Muitos produtos cosméticos têm produtos naturais na formulação que executam uma função biológica específica, porém estes produtos devem ser avaliados quanto a sua eficácia e toxicidade. O objetivo deste artigo é abordar a sustentabilidade, cosméticos naturais e orgânicos, considerando os aspectos regulatórios, do consumidor e os aspectos de eficácia e toxicológicos

Eco-friendly and miniaturized analytical method for quantification of Rifaximin in tablets

Rifaximin is an oral antimicrobial, semisynthetic and nonabsorbable with minimal adverse effects that act locally in the gastrointestinal tract. Rifaximin does not have standardized methods of analysis for the tablets evaluation in official compendiums. The objective of this study is to develop and validate an analytical method for the quantification of rifaximin in tablets by spectrophotometry in the ultraviolet region, aiming at a miniaturized and eco-friendly method. The method was performed using 700 μL cuvette and purified water: ethanol (4:1, v/v) as diluent. The wavelength used was 233 nm and the range of concentrations was 4-14 µg mL-1. It was linear with correlation coefficient greater than 0.9999, precise with relative standard deviation equal 0.80%, 1.19% and 1.19% for intraday, interday and interanalyst precision, respectively, exact with average recovery of 100.56%, selective against the presence of interferents such as impuruties, matrix compouds and solvents used and robust with the change of ethyl alcohol brand and proportion used as diluent. The method developed presents advantages as, minimum waste generation, reduction in amount of sample, standard and solvents used and reduction in time of analysis. Then this method can be used in rotine analysis of rifaximin tablets as a alternative method, reliable, effective, really fast, low cost, eco-friendly and miniaturized. This study contemplates a current and innovative topic which is extremely important for the area of Quality Control of drugs and medicines and for the sustainable Green Analytical Chemistry

Nanotechnology-based drug delivery systems for treatment of oral cancer: a review

Oral cancer (oral cavity and oropharynx) is a common and aggressive cancer that invades local tissue, can cause metastasis, and has a high mortality rate. Conventional treatment strategies, such as surgery and chemoradiotherapy, have improved over the past few decades; however, they remain far from optimal. Currently, cancer research is focused on improving cancer diagnosis and treatment methods (oral cavity and oropharynx) nanotechnology, which involves the design, characterization, production, and application of nanoscale drug delivery systems. In medicine, nanotechnologies, such as polymeric nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, gold nanoparticles, hydrogels, cyclodextrin complexes, and liquid crystals, are promising tools for diagnostic probes and therapeutic devices. The objective of this study is to present a systematic review of nanotechnology-based drug delivery systems for oral cancers.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)PADC/FCF-UNESP (Araraquara, Brazil)Sao Paulo State Univ, UNESP, Sch Pharmaceut Sci, Dept Drugs & Pharmaceut, BR-14801902 Sao Paulo, BrazilSao Paulo State Univ, UNESP, Sch Pharmaceut Sci, Dept Drugs & Pharmaceut, BR-14801902 Sao Paulo, Brazi

Piperine: Chemical, biological and nanotechnological applications

Piperine (PIP) is an alkaloid present in several species of piper, mainly Piper nigrum Linn. and P. longum, among other species. The present article provides a comprehensive review of PIP research in the last years concerning its chemical properties, synthesis, absorption, metabolism, bioavailability and toxicity. The reviewed PIP literature has shown many pharmacological properties, such as antidiabetic, antidiarrheal, antioxidant, antibacterial, and antiparasitic activity of PIP. However, its low solubility and absorption make its application challenging. This review also includes advances in the development of nanosystems containing PIP, including liposomes, micelles, metal nanoparticles, nanofibers, polymeric nanoparticles, and solid-lipid nanoparticles. Finally, we discuss different in vitro and in vivo studies to evaluate the biological activity of this drug, as well as some methods for the synthesis of nanosystems and their physical characteristics

Nanotechnology-based drug delivery systems for the treatment of Alzheimer’s disease

Alzheimer's disease is a neurological disorder that results in cognitive and behavioral impairment. Conventional treatment strategies, such as acetylcholinesterase inhibitor drugs, often fail due to their poor solubility, lower bioavailability, and ineffective ability to cross the blood-brain barrier. Nanotechnological treatment methods, which involve the design, characterization, production, and application of nanoscale drug delivery systems, have been employed to optimize therapeutics. These nanotechnologies include polymeric nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, microemulsion, nanoemulsion, and liquid crystals. Each of these are promising tools for the delivery of therapeutic devices to the brain via various routes of administration, particularly the intranasal route. The objective of this study is to present a systematic review of nanotechnology-based drug delivery systems for the treatment of Alzheimer's disease.Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil.Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil

Advanced porous materials for antimicrobial treatment

Infectious diseases are a global public health concern generated by uncontrolled uses of antimicrobials resulting in multidrug-resistant (MDR) pathogens. The antimicrobial resistance (AMR) has made explicit the ineffective action of the current medicines and vaccines. Rapid diagnosis and effective treatment are the keys to reduce the capacity of MDR pathogens spreading very fast, avoiding high socioeconomic impact, severe and prolonged illness and death. Advanced porous materials have emerged as promising alternatives to the conventional diagnoses and therapy due to their low-cost production, high biocompatibility, adjustable porous structure, large surface area, easy surface functionalization and capacity of loading high drugs amount. In this review, we first highlighted the current strategies to fight against infectious diseases. Then, we introduce the main advanced porous materials used in infectious diseases, including mesoporous silica nanoparticles (MSNs), porous silicon nanoparticles (PSiNPs), metal?organic frameworks (MOFs), covalent?organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs) and porous carbon materials. The strategies to fabricate these materials and their characterization for the application in the recent years for antimicrobial treatment is also discussed. Finally, we present an overview outlook and challenges on the future application of such materials for infectious diseases

Skin delivery and in vitro biological evaluation of trans-resveratrol-loaded solid lipid nanoparticles for skin disorder therapies

The aim of this study was to evaluate the skin delivery and in vitro biological activity of trans-resveratrol (RES)-loaded solid lipid nanoparticles (SLNs). The SLNs were composed of stearic acid, poloxamer 407, soy phosphatidylcholine (SPC), an aqueous phase and 0.1% RES. The particle size, polydispersity index (PdI) and zeta potential were analyzed by dynamic light scattering (DLS). The SLNs were analyzed by scanning electron microscopy (SEM-FEG) and differential scanning calorimetry (DSC). In vitro RES-SLN skin permeation/retention assays were conducted, and their tyrosinase inhibitory activity was evaluated. An MTT reduction assay was performed on HaCat keratinocytes to determine in vitro cytotoxicity. The formulations had average diameter lower than 200 nm, the addition of SPC promoted increases in PdI in the RES-SLNs, but decreases PdI in the RES-free SLNs and the formulations exhibited zeta potentials smaller than −3 mV. The DSC analysis of the SLNs showed no endothermic peak attributable to RES. Microscopic analysis suggests that the materials formed had nanometric size distribution. Up to 45% of the RES permeated through the skin after 24 h. The RES-loaded SLNs were more effective than kojic acid at inhibiting tyrosinase and proved to be non-toxic in HaCat keratinocytes. The results suggest that the investigated RES-loaded SLNs have potential use in skin disorder therapies21CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçãosem informação2011/16888-5; 2012/19568-4; 2013/21500-