title: Dual sustained release delivery system for multiple route therapy of an antiviral drug.
abstract: BACKGROUND
  The first successful molecule against herpes infections was Acyclovir, which competes with new generations in the market, with its potential activity. The major physicochemical constraints and pharmacokinetics of Acyclovir such as low solubility, poor permeability, less half-life, high dose has initiated many researchers to develop diverse modified release dosage forms.
  
  
  OBJECTIVE
  The objective of this work was to design polymeric nanoparticles of Acyclovir and then incorporate the drug-loaded nanoparticles within an in situ gelling system to provide dual sustained release effect, whereby the duration of action and bioavailability through different routes of administration could be improved.
  
  
  METHODS
  The formulation was designed through 3(2) factorial design, first developing the nanoparticles using Polycaprolactone and Pluronic F127 by Solvent evaporation process, followed by dispersion of the suspended nanoparticles into thermosensitive in situ gelling system of Pluronic F127 with Carbopol.
  
  
  CONCLUSIONS
  The characterization of the nanoparticles and its sol-gel system performed through zeta sizer, SEM, XRD, TG-DSC, FTIR and rheology helped to optimize the formulation. The drug release could be sustained to 60% and 30% at eight hours, for the nanoparticles and their in situ gel systems, respectively, with non-Fickian diffusion mechanism of drug release. The test for % cell viability with NIH3T3 cell line revealed low level of toxicity for the nanoparticles.
  
  
  CONCLUSIONS
  The statistical significance obtained for the trail formulations experimentally proved its suitability for this dosage form design to achieve desired level of drug release.
authors.affiliation: Department of Pharmaceutical Technology, School of Chemical and Biotechnology, SASTRA University , Thanjavur -- 613 401, Tamil Nadu , India.
authors.forename: D
authors.initials: D
authors.lastname: Ramyadevi
authors.forename: P
authors.initials: P
authors.lastname: Sandhya
mesh_terms: D000212:Acyclovir / Q000008:administration & dosage / Q000737:chemistry*; D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry*; D004333:Drug Administration Routes; D016503:Drug Delivery Systems / Q000379:methods*; D006041:Goats; D051379:Mice; D041681:NIH 3T3 Cells; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry*; D009924:Organ Culture Techniques
chemical_list: D000998:Antiviral Agents; D003692:Delayed-Action Preparations; D000212:Acyclovir
keywords: Acyclovir; in situ gel; nanoparticles; pluronic; polycaprolactone