title: Solid lipid nanoparticles as vesicles for oral delivery of olmesartan medoxomil: formulation, optimization and in vivo evaluation.
abstract: OBJECTIVE
  Olmesartan medoxomil (OLM) is an antihypertensive drug with low oral bioavailability (28%) resulting from poor aqueous solubility, presystemic metabolism and P-glycoprotein mediated efflux. The present investigation studies the role of lipid nanocarriers in enhancing the OLM bioavailability through oral delivery.
  
  
  METHODS
  Solid lipid nanoparticles (SLN) were prepared by solvent emulsion-evaporation method. Statistical tools like regression analysis and Pareto charts were used to detect the important factors effecting the formulations. Formulation and process parameters were then optimized using mean effect plot and contour plots. The formulations were characterized for particle size, size distribution, surface charge, percentage of drug entrapped in nanoparticles, drug-excipients interactions, powder X-ray diffraction analysis and drug release in vitro.
  
  
  CONCLUSIONS
  The optimized formulation comprised glyceryl monostearate, soya phosphatidylcholine and Tween 80 as lipid, co-emulsifier and surfactant, respectively, with an average particle size of 100 nm, PDI 0.291, zeta potential of -23.4 mV and 78% entrapment efficiency. Pharmacokinetic evaluation in male Sprague Dawley rats revealed 2.32-fold enhancement in relative bioavailability of drug from SLN when compared to that of OLM plain drug on oral administration.
  
  
  CONCLUSIONS
  In conclusion, SLN show promising approaches as a vehicle for oral delivery of drugs like OLM.
authors.affiliation: a Department of Pharmaceutics , National Institute of Pharmaceutical Education and Research (NIPER) - Hyderabad , Hyderabad , India.
authors.forename: Mounika
authors.initials: M
authors.lastname: Nooli
authors.affiliation: a Department of Pharmaceutics , National Institute of Pharmaceutical Education and Research (NIPER) - Hyderabad , Hyderabad , India.
authors.forename: Naveen
authors.initials: N
authors.lastname: Chella
authors.affiliation: b Medicinal Chemistry and Pharmacology Division , Council of Scientific and Industrial Research-Indian Institute of Chemical Technology (CSIR-IICT) , Hyderabad , India.
authors.forename: Hitesh
authors.initials: H
authors.lastname: Kulhari
authors.affiliation: a Department of Pharmaceutics , National Institute of Pharmaceutical Education and Research (NIPER) - Hyderabad , Hyderabad , India.
authors.forename: Nalini R
authors.initials: NR
authors.lastname: Shastri
authors.affiliation: b Medicinal Chemistry and Pharmacology Division , Council of Scientific and Industrial Research-Indian Institute of Chemical Technology (CSIR-IICT) , Hyderabad , India.
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Sistla
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000737:chemistry; D000284:Administration, Oral; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004337:Drug Carriers / Q000737:chemistry; D004355:Drug Stability; D004655:Emulsions / Q000737:chemistry / Q000493:pharmacokinetics; D005079:Excipients / Q000737:chemistry; D008055:Lipids / Q000737:chemistry*; D008297:Male; D053758:Nanoparticles / Q000737:chemistry*; D000068557:Olmesartan Medoxomil / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000959:Antihypertensive Agents; D004337:Drug Carriers; D004655:Emulsions; D005079:Excipients; D008055:Lipids; D013501:Surface-Active Agents; D000068557:Olmesartan Medoxomil
keywords: Bioavailability; P-gp efflux; Pareto chart; lymphatic transport; olmesartan medoxomil; presystemic metabolism