title: Sodium Acetate Coated Tenofovir-Loaded Chitosan Nanoparticles for Improved Physico-Chemical Properties.
abstract: OBJECTIVE
  It is hypothesized that sodium acetate (SA) can be used for in situ coating of drug loaded chitosan NPs for improved physico-chemical properties.
  
  
  METHODS
  Tenofovir (TFV) is used as a model drug. Uncoated chitosan NPs are prepared by ionic gelation. SA is generated in situ from half neutralization of acetic acid with sodium hydroxide, and coats chitosan NPs during freeze-drying. The NPs' physico-chemical properties [e.g., particle mean diameters (PMD) zeta potential (ζ), EE%, drug release profile, morphology] are characterized by dynamic light scattering, spectrophotometry, Korsmeyer-Peppas model, transmission electron microscopy (TEM), respectively. Melting point (MP), non-aqueous titration, Fourier transform infrared (FTIR) analysis, and powder X-ray diffractometry (XRD) pattern evaluate the SA coated chitosan NPs. The NPs' cytotoxicity on macrophages Raw 264.7 is assessed by neutral red, resazurin, nitrite oxide (NO) and cytokines assays.
  
  
  RESULTS
  Collectively, FTIR, ζ, XRD, MP, and TEM data confirm that SA coats chitosan NPs. The PMD range is 136-348 nm (uncoated) and 171-379 nm (coated NPs). The ζ values range is +24.3-28.5 mV (uncoated) and 0.1-3.1 mV (coated NPs). The EE% ranges from 5.5 to 11.7% (uncoated NPs) and increased up to 86.3-92.7%(8-17-fold) after coating. The SA also prevents NPs aggregation during the freeze-drying and aqueous dispersion. The core-shell NPs exhibited a sustain release of TFV following anomalous transport mechanism (R(2) ~ 0.99). The coated NPs are non-cytotoxic (cell viability ~100%) and without any proinflammatory response.
  
  
  CONCLUSIONS
  This SA coating chitosan NPs mechanism may be useful for (i) efficient encapsulation, (ii) stabilizing colloidal dispersions, (iii) controlling the release and solubility of bioactive agents.
authors.affiliation: Laboratory of Future Nanomedicines and Theoretical Chronopharmaceutics, Division of Pharmaceutical Sciences, University of Missouri-Kansas City, New Health Sciences Building, 2464 Charlotte Street, Kansas City, Missouri, 64108, USA.
authors.forename: Albert N
authors.initials: AN
authors.lastname: Ngo
authors.affiliation: Laboratory of Future Nanomedicines and Theoretical Chronopharmaceutics, Division of Pharmaceutical Sciences, University of Missouri-Kansas City, New Health Sciences Building, 2464 Charlotte Street, Kansas City, Missouri, 64108, USA.
authors.forename: Miezan J M
authors.initials: MJ
authors.lastname: Ezoulin
authors.affiliation: Department of Geosciences, University of Missouri-Kansas City, 420 Flarsheim Hall, 5110 Rockhill Rd., Kansas City, Missouri, 64110, USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Murowchick
authors.affiliation: Department of Chemistry, University of Missouri-Kansas City, 510D Flarsheim Hall, 5110, Rockhill Rd., Kansas City, Missouri, 64110, USA.
authors.forename: Andrea D
authors.initials: AD
authors.lastname: Gounev
authors.affiliation: Laboratory of Future Nanomedicines and Theoretical Chronopharmaceutics, Division of Pharmaceutical Sciences, University of Missouri-Kansas City, New Health Sciences Building, 2464 Charlotte Street, Kansas City, Missouri, 64108, USA. youanb@umkc.edu.
authors.forename: Bi-Botti C
authors.initials: BB
authors.lastname: Youan
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage* / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D065546:Drug Liberation; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D019346:Sodium Acetate / Q000737:chemistry*; D012995:Solubility; D000068698:Tenofovir / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D000998:Antiviral Agents; D004337:Drug Carriers; D019346:Sodium Acetate; D048271:Chitosan; D000068698:Tenofovir
keywords: coated chitosan nanoparticles; efficient encapsulation; sodium acetate; tenofovir; water-soluble drugs