Poly (-caprolactone) microparticles containing Levobunolol HCl prepared by a multiple emulsion (W/O/W) solvent evaporation technique: Effects of some formulation parameters on microparticle characteristics

Karatas A., Sonakin O., KILIÇARSLAN M., Baykara T.

JOURNAL OF MICROENCAPSULATION, cilt.26, sa.1, ss.63-74, 2009 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 26 Sayı: 1
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1080/02652040802141039
  • Dergi Adı: JOURNAL OF MICROENCAPSULATION
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.63-74
  • Anahtar Kelimeler: Levobunol HCl-loaded microparticles, poly (-caprolactone), polyvinylalcohol, multiple emulsion (W, O, W) solvent evaporation, thermally reversible gel, drug release, OCULAR DELIVERY-SYSTEM, DRUG-RELEASE, IN-VITRO, POLY(EPSILON-CAPROLACTONE) MICROPARTICLES, BIODEGRADABLE NANOPARTICLES, PROPRANOLOL HYDROCHLORIDE, ACID) NANOPARTICLES, PLGA NANOPARTICLES, POLYVINYL-ALCOHOL, MICROSPHERES
  • Ankara Üniversitesi Adresli: Evet

Özet

The aim of this study was to prepare poly (-caprolactone) (PCL) microparticles of Levobunolol HC1 (L-HC1) for use as an anti-glaucomatous drug to the eye. The double emulsion (W/O/W) solvent evaporation technique was used for encapsulating L-HC1 as a hydrophilic drug. The study examined the impact of different factors including the pH and volume of the external aqueous phase, the concentration of polyvinylalcohol (PVA) and pluronic F68 (PF68) used as stabilizers and drug/polymer ratios on the characteristics of the microparticles. Scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were used to identify the physical state of the drug and polymer. The zeta potential of the particles was also identified. Entrapment efficiency was found to be highest with a 0.5% PVA concentration and 100 mL volume of external aqueous phase at pH 12. The high efficiency was due to a reduction in the degree of drug ionization. The microparticles were spherical and appropriately sized for ophthalmic application. Drug release from the microparticles appears to consist of two components, with an initial rapid release followed by a slower stage. Drug release was slower when the microparticle was incorporated into the thermally reversible gel (Pluronic F127) in comparison to drug release from the free drug incorporated into the gel and drug release from the free microparticle.