title: Alendronate PLGA microspheres with high loading efficiency for dental applications.
abstract: OBJECTIVE
  Alendronate sodium, used systemically as a bone protective agent, proved to also be effective locally in various dental bone applications. Development of alendronate-loaded microspheres with high loading efficiency for such applications would be greatly challenged by the hydrophilicity and low MW of the drug. The aim of this study was to incorporate alendronate sodium, into poly (lactide-co-glycolide) (PLGA) microspheres (MS) with high loading efficiency.
  
  
  METHODS
  Three multiple emulsion methods: water-in-oil-in-water (W/O/W), water-in-oil-in-oil (W/O(1)/O(2)) and solid-in-oil-in-oil (S/O(1)/O(2)) were tested. In addition to entrapment efficiency, MS were characterized for surface morphology, particle size, in vitro drug release and in vitro degradation of the polymer matrix. Alendronate microspheres with maximum drug loading and good overall in vitro performance were obtained using the W/O(1)/O(2) emulsion technique.
  
  
  RESULTS
  Drug release from the microspheres exhibited a triphasic release pattern over a period of 13 days, the last fast release phase being associated with more rapid degradation of the PLGA matrix.
  
  
  CONCLUSIONS
  Biocompatible, biodegradable PLGA microspheres incorporating alendronate sodium with high loading efficiency obtained in this study may offer promise as a delivery system for bisphosphonates in dental and probably other clinical applications.
authors.affiliation: Faculty of Pharmacy, Department of Pharmaceutics, University of Alexandria, Tissue Engineering Laboratories, Alexandria, Egypt.
authors.forename: Eman H
authors.initials: EH
authors.lastname: Nafea
authors.forename: Magda A
authors.initials: MA
authors.lastname: El-Massik
authors.forename: Labiba K
authors.initials: LK
authors.lastname: El-Khordagui
authors.forename: Mona K
authors.initials: MK
authors.lastname: Marei
authors.forename: Nawal M
authors.initials: NM
authors.lastname: Khalafallah
mesh_terms: D019386:Alendronate / Q000737:chemistry*; D004337:Drug Carriers; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D019344:Lactic Acid / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry
chemical_list: D004337:Drug Carriers; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D012964:Sodium; D019386:Alendronate