Controlled Release of Lysozyme from Double-Walled Poly(Lactide-Co-Glycolide) (PLGA) Microspheres
Faculty of Pharmacy, International Islamic University Malaysia, Kuantan 25200, Malaysia
Department of Chemistry, University of Rajshahi, Rajshahi 6205, Bangladesh
Institute for Community Development & Quality of Life (i-CODE), Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Terengganu, Malaysia
Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Terengganu, Malaysia
Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
School of Ocean Engineering, Universiti Malaysia Terengganu, 21300 Kuala Nerus, Terengganu, Malaysia
Faculty of Pharmacy, Cyberjaya University College of Medical Sciences, Cyberjaya 63000, Malaysia
Author to whom correspondence should be addressed.
Polymers 2017, 9(10), 485; https://doi.org/10.3390/polym9100485
Received: 19 September 2017 / Revised: 28 September 2017 / Accepted: 28 September 2017 / Published: 3 October 2017
(This article belongs to the Special Issue Emulsion Polymerization)
Double-walled microspheres based on poly(lactide-co-glycolide) (PLGA) are potential delivery systems for reducing a very high initial burst release of encapsulated protein and peptide drugs. In this study, double-walled microspheres made of glucose core, hydroxyl-terminated poly(lactide-co-glycolide) (Glu-PLGA), and carboxyl-terminated PLGA were fabricated using a modified water-in-oil-in-oil-in-water (w1/o/o/w2) emulsion solvent evaporation technique for the controlled release of a model protein, lysozyme. Microspheres size, morphology, encapsulation efficiency, lysozyme in vitro release profiles, bioactivity, and structural integrity, were evaluated. Scanning electron microscopy (SEM) images revealed that double-walled microspheres comprising of Glu-PLGA and PLGA with a mass ratio of 1:1 have a spherical shape and smooth surfaces. A statistically significant increase in the encapsulation efficiency (82.52% ± 3.28%) was achieved when 1% (w/v) polyvinyl alcohol (PVA) and 2.5% (w/v) trehalose were incorporated in the internal and external aqueous phase, respectively, during emulsification. Double-walled microspheres prepared together with excipients (PVA and trehalose) showed a better control release of lysozyme. The released lysozyme was fully bioactive, and its structural integrity was slightly affected during microspheres fabrication and in vitro release studies. Therefore, double-walled microspheres made of Glu-PLGA and PLGA together with excipients (PVA and trehalose) provide a controlled and sustained release for lysozyme.