@article{2959181,
    title = "Chitosan Derivatives with Mucoadhesive and Antimicrobial Properties for Simultaneous Nanoencapsulation and Extended Ocular Release Formulations of Dexamethasone and Chloramphenicol Drugs",
    author = "Aikaterini Karava and Maria Lazaridou and Stavroula Nanaki and Georgia Michailidou and Evi Christodoulou and Margaritis Kostoglou and Hermis Iatrou and Dimitrios N. Bikiaris",
    journal = "Pharmaceutical Executive Europe",
    year = "2020",
    volume = "12",
    number = "6",
    pages = "594",
    publisher = "MDPI AG",
    doi = "10.3390/pharmaceutics12060594",
    keywords = "2 acrylamido 2 methyl 1 propanesulfonic acid;  chitosan derivative;  chloramphenicol derivative;  dexamethasone;  nanocarrier;  polymer;  tripolyphosphate;  unclassified drug;  [2 (methacryloyloxy)ethyl]dimethyl (3 sulfopropyl)ammonium hydroxide, antimicrobial activity;  Article;  bacterial growth;  controlled study;  cross linking;  cytotoxicity;  drug formulation;  drug structure;  Escherichia coli;  Fourier transform infrared spectroscopy;  gelation;  growth inhibition;  mucoadhesion;  nanoencapsulation;  nonhuman;  particle size;  photon correlation spectroscopy;  polymerization;  Staphylococcus aureus;  sustained drug release",
    abstract = "The aim of this work was to evaluate the effectiveness of neat chitosan (CS) and its derivatives with 2-acrylamido-2-methyl-1-propanesulfonic acid (AΑMPS) and [2- (methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (MEDSP) as appropriate nanocarriers for the simultaneous ocular administration of dexamethasone sodium phosphate (DxP) and chloramphenicol (CHL). The derivatives CS-AΑMPS and CS-MEDSP have been synthesized by free-radical polymerization and their structure has been proved by Fourier- Transformed Infrared Spectroscopy (FT-IR) spectroscopy. Both derivatives exhibited low cytotoxicity, enhanced mucoadhesive properties and antimicrobial activity against Staphylococcus aureus (S.aureus) and Escherichia coli (E. coli). Encapsulation was performed via ionic crosslinking gelation using sodium tripolyphosphate (TPP) as the crosslinking agent. Dynamic light scattering measurements (DLS) showed that the prepared nanoparticles had bimodal distribution and sizes ranging from 50–200 nm and 300–800 nm. Drugs were encapsulated in their crystalline (CHL) or amorphous (DexSP) form inside nanoparticles and their release rate was dependent on the used polymer. The CHL dissolution rate was substantially enhanced compared to the neat drug and the release time was extended up to 7 days. The release rate of DexSP was much faster than that of CHL and was prolonged up to 3 days. Drug release modeling unveiled that diffusion is the main release mechanism for both drugs. Both prepared derivatives and their drug-loaded nanoparticles could be used for extended and simultaneous ocular release formulations of DexSP and CHL drugs. © 2020 by the authors. Licensee MDPI, Basel, Switzerland."
}