PLGA Microparticles Entrapping Chitosan-Based Nanoparticles for the Ocular Delivery of Ranibizumab.
Age-related macular degeneration (AMD) is the leading cause of certified vision loss worldwide. The standard treatment for neovascular AMD involves repeated intravitreal injections of therapeutic proteins directed against vascular endothelial growth factor, such as ranibizumab. Biodegradable polymers, such as poly(lactic-co-glycolic acid) (PLGA), form delivery vehicles which can be used to treat posterior segment eye diseases, but suffer from poor protein loading and release. This work describes a "system-within-system", PLGA microparticles incorporating chitosan-based nanoparticles, for improved loading and sustained intravitreal delivery of ranibizumab. Chitosan-N-acetyl-l-cysteine (CNAC) was synthesized and its synthesis confirmed using FT-IR and (1)H NMR. Chitosan-based nanoparticles composed of CNAC, CNAC/tripolyphosphate (CNAC/TPP), chitosan, chitosan/TPP (chit/TPP), or chit/TPP-hyaluronic acid (chit/TPP-HA) were incorporated in PLGA microparticles using a modified w/o/w double emulsion method. Nanoparticles and final nanoparticles-within-microparticles were characterized for their protein-nanoparticle interaction, size, zeta potential, morphology, protein loading, stability, in vitro release, in vivo antiangiogenic activity, and effects on cell viability. The prepared nanoparticles were 17-350 nm in size and had zeta potentials of -1.4 to +12 mV. Microscopic imaging revealed spherical nanoparticles on the surface of PLGA microparticles for preparations containing chit/TPP, CNAC, and CNAC/TPP. Ranibizumab entrapment efficiency in the preparations varied between 13 and 69% and was highest for the PLGA microparticles containing CNAC nanoparticles. This preparation also showed the slowest release with no initial burst release compared to all other preparations. Incorporation of TPP to this formulation increased the rate of protein release and reduced entrapment efficiency. PLGA microparticles containing chit/TPP-HA showed the fastest and near-complete release of ranibizumab. All of the prepared empty particles showed no effect on cell viability up to a concentration of 12.5 mg/mL. Ranibizumab released from all preparations maintained its structural integrity and in vitro activity. The chit/TPP-HA preparation enhanced antiangiogenic activity and may provide a potential biocompatible platform for enhanced antiangiogenic activity in combination with ranibizumab. In conclusion, the PLGA microparticles containing CNAC nanoparticles showed significantly improved ranibizumab loading and release profile. This novel drug delivery system may have potential for improved intravitreal delivery of therapeutic proteins, thereby reducing the frequency, risk, and cost of burdensome intravitreal injections.
University of Hertfordshire , Hatfield, United Kingdom.
Naba
N
Elsaid
King's College London , London, United Kingdom.
Timothy L
TL
Jackson
University College London School of Pharmacy , London, United Kingdom.
Zeeneh
Z
Elsaid
University College London School of Pharmacy , London, United Kingdom.
Aljawharah
A
Alqathama
University College London School of Pharmacy , London, United Kingdom.
Satyanarayana
S
Somavarapu
D000111:Acetylcysteine / Q000737:chemistry; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000031:analogs & derivatives / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D006820:Hyaluronic Acid / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry*; D008268:Macular Degeneration / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011122:Polyphosphates / Q000737:chemistry; D000069579:Ranibizumab / Q000008:administration & dosage* / Q000737:chemistry* / Q000627:therapeutic use; D017550:Spectroscopy, Fourier Transform Infrared
D011122:Polyphosphates; C540141:chitosan-N-acetylcysteine conjugate; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D006820:Hyaluronic Acid; D048271:Chitosan; C005692:triphosphoric acid; D000111:Acetylcysteine; D000069579:Ranibizumab
age-related macular degeneration; antiangiogenic; chitosan; hyaluronic acid; ranibizumab; sustained delivery