title: Indomethacin-loaded solid lipid nanoparticles for ocular delivery: development, characterization, and in vitro evaluation.
abstract: OBJECTIVE
  The goal of this study was to develop and characterize indomethacin-loaded solid lipid nanoparticles (IN-SLNs; 0.1% w/v) for ocular delivery.
  
  
  METHODS
  Various lipids, homogenization pressures/cycles, Tween 80 fraction in the mixture of surfactants (Poloxamer 188 and Tween 80; total surfactant concentration at 1% w/v), and pH were investigated in the preparation of the IN-SLNs. Compritol(®) 888 ATO was selected as the lipid phase for the IN-SLNs, as indomethacin exhibited a highest distribution coefficient and solubility in this phase.
  
  
  RESULTS
  Homogenization at 15,000 psi for 6 cycles resulted in the smallest particle size. Increase in the Poloxamer 188 fraction resulted in decrease in the entrapment efficiency (EE). The mean particle size, polydispersity index, zeta-potential, and EE of the optimized formulation were 140 nm, 0.16, -21 mV, and 72.0%, respectively. IN-SLNs were physically stable post-sterilization and on storage for a period of 1 month (last timepoint tested). A dramatic increase in the chemical stability and in vitro corneal permeability of indomethacin was observed with the IN-SLN formulation in comparison to the indomethacin solution- (0.1% w/v) and indomethacin hydroxypropyl-beta-cyclodextrin-based formulations (0.1% w/v).
  
  
  CONCLUSIONS
  Results from this study suggest that topical IN-SLNs could significantly improve ocular bioavailability of indomethacin.
authors: Department of Pharmaceutics, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
authors: Ketan
authors: K
authors: Hippalgaonkar
authors: Goutham R
authors: GR
authors: Adelli
authors: Kanchan
authors: K
authors: Hippalgaonkar
authors: Michael A
authors: MA
authors: Repka
authors: Soumyajit
authors: S
authors: Majumdar
mesh_terms: D002626:Chemistry, Pharmaceutical; D003315:Cornea / Q000187:drug effects* / Q000378:metabolism; D016503:Drug Delivery Systems / Q000379:methods*; D004341:Drug Evaluation / Q000379:methods; D006801:Humans; D007213:Indomethacin / Q000008:administration & dosage* / Q000737:chemistry / Q000378:metabolism; D008055:Lipids / Q000008:administration & dosage* / Q000737:chemistry; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D009924:Organ Culture Techniques
chemical_list: D008055:Lipids; D007213:Indomethacin