title: Rheological behavior, zeta potential, and accelerated stability tests of Buriti oil (Mauritia flexuosa) emulsions containing lyotropic liquid crystals.
abstract: BACKGROUND
  It is well known that the Amazon region presents a huge biodiversity; therefore, countless natural resources are being employed in the production of phytocosmetics and phytomedicines.
  
  
  OBJECTIVE
  The purpose of this work was to obtain emulsions produced with Buriti oil and non-ionic surfactants.
  
  
  METHODS
  Two surfactant systems were employed (Steareth-2 associated to Ceteareth-5 and to Ceteareth-20) to produce the emulsions using phase diagram method. Emulsions were obtained by echo-planar imaging method at 75°C. Rheological behavior and zeta potential were evaluated, and accelerated stability tests were performed.
  
  
  RESULTS
  All emulsions analyzed presented pseudoplastic behavior. Zeta potential values were obtained between -14.2 and -53.3 mV. The formulations did not show changes in either physical stability, pH, or rheological behavior after accelerated stability tests. Significant differences were observed only after temperature cycling test.
  
  
  CONCLUSIONS
  Based on these results, the emulsions obtained could be considered as promising delivery systems.
authors: Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil. cinthiafz@yahoo.com.br
authors: Cinthia Fernanda
authors: CF
authors: Zanatta
authors: Anne Miwa Callejón
authors: AM
authors: de Faria Sato
authors: Flavio Bueno
authors: FB
authors: de Camargo
authors: Patrícia Maria Berardo Gonçalves Maia
authors: PM
authors: Campos
authors: Pedro Alves
authors: PA
authors: Rocha-Filho
mesh_terms: D002338:Carotenoids / Q000008:administration & dosage* / Q000737:chemistry; D016503:Drug Delivery Systems; D004355:Drug Stability; D004356:Drug Storage; D004655:Emulsions; D006863:Hydrogen-Ion Concentration; D050866:Liquid Crystals / Q000737:chemistry; D010938:Plant Oils / Q000008:administration & dosage* / Q000737:chemistry; D012212:Rheology; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature
chemical_list: D004655:Emulsions; D010938:Plant Oils; D013501:Surface-Active Agents; C548591:buriti oil; D002338:Carotenoids