title: Poly(lactide-co-glycolide) nanocapsules containing benzocaine: influence of the composition of the oily nucleus on physico-chemical properties and anesthetic activity.
abstract: OBJECTIVE
  The aim of this work was to investigate the influence of the oily nucleus composition on physico-chemical properties and anesthetic activity of poly (lactide-co-glycolide) nanocapsules with benzocaine.
  
  
  METHODS
  Nanocapsules containing benzocaine were prepared with three different oily nucleus composition and characterized by mean diameter, polydispersivity, zeta potential, pH and stability were investigated as a function of time. In vitro release kinetics were performed in a system with two compartments separated by a cellulose membrane. Intensity and duration of analgesia were evaluated in rats by sciatic nerve blockade.
  
  
  RESULTS
  The greatest stability, slower release profile and improvement in the local anesthetic activity of BZC were obtained with the formulation using USP mineral oil as component.
  
  
  CONCLUSIONS
  Results from our study provide useful perspectives on selection of the primary materials needed to produce suspensions of polymeric nanocapsules able to act as carriers of BZC, with potential future application in the treatment of pain.
authors.affiliation: Department of Environmental Engineering, São Paulo State University, Av. Três de Março, 511, Sorocaba, SP 18087-180, Brazil.
authors.forename: Nathalie Ferreira Silva
authors.initials: NF
authors.lastname: de Melo
authors.forename: Renato
authors.initials: R
authors.lastname: Grillo
authors.forename: Viviane Aparecida
authors.initials: VA
authors.lastname: Guilherme
authors.forename: Daniele Ribeiro
authors.initials: DR
authors.lastname: de Araujo
authors.forename: Eneida
authors.initials: E
authors.lastname: de Paula
authors.forename: André Henrique
authors.initials: AH
authors.lastname: Rosa
authors.forename: Leonardo Fernandes
authors.initials: LF
authors.lastname: Fraceto
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000737:chemistry*; D000818:Animals; D001566:Benzocaine / Q000737:chemistry* / Q000494:pharmacology*; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000008:administration & dosage / Q000737:chemistry*; D008297:Male; D051379:Mice; D053769:Nanocapsules / Q000008:administration & dosage / Q000737:chemistry*; D009821:Oils / Q000737:chemistry; D010146:Pain / Q000188:drug therapy; D010316:Particle Size; D011100:Polyglycolic Acid / Q000008:administration & dosage / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D012995:Solubility; D013535:Suspensions / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D000779:Anesthetics, Local; D004337:Drug Carriers; D053769:Nanocapsules; D009821:Oils; D013535:Suspensions; C020253:cellulose ester plastic; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D002482:Cellulose; D001566:Benzocaine