title: Investigating triazine-based modification of hyaluronan using statistical designs.
abstract: Hyaluronan (HA) and its derivatives have been extensively researched for many biomedical applications. To precisely tailor the property of HA by derivatizing it to a pre-determined extent is challenging, yet critical. In this paper, we used 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and N-methylmorpholine (NMM) to derivatize HA via a triazine-based coupling reaction. Using a fractional factorial (FF) design, we observed that water content in the solvent, and molar ratios of CDMT and NaHCO3 to the carboxylate were the significant factors controlling the derivatization. We investigated how the effect of each factor changes as reaction conditions change. Moreover, by altering the amount of CDMT and NaHCO3, we developed a cubic regression model for precise control of the extent of derivatization using a response surface methodology (RSM) with a D-optimal design. No spurious peaks were detected by (1)H NMR spectrum and only 10% decrease of molecular weight of the derivatized HA was determined by GPC. The HA with 6% modification was relatively biocompatible up to 15 mg/mL.
authors.affiliation: Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO, USA.
authors.forename: Jue
authors.initials: J
authors.lastname: Liang
authors.affiliation: Statistics Technology Center, Monsanto Company, Saint Louis, Missouri, USA.
authors.forename: Lulu
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO, USA.
authors.forename: Jessica J
authors.initials: JJ
authors.lastname: Struckhoff
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, MO, USA; Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO, USA; Research and Development, Veterans Affairs Health Care System, Saint Louis, MO, USA. Electronic address: ravi@vision.wustl.edu.
authors.forename: Nathan
authors.initials: N
authors.lastname: Ravi
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D006820:Hyaluronic Acid / Q000737:chemistry* / Q000633:toxicity; D009682:Magnetic Resonance Spectroscopy; D009025:Morpholines / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D014227:Triazines / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D009025:Morpholines; D013438:Sulfhydryl Compounds; D014227:Triazines; D014867:Water; C038816:4-methylmorpholine; D006820:Hyaluronic Acid
keywords: 2-chloro-4,6-dimethoxy-1,3,5-triazine (PubChem CID: 18450); 4-methylmorpholine (PubChem CID: 7972); Amidation; Cystamine dihydrochloride (PubChem CID: 5941); Fractional-factorial design; Hyaluronan; Response surface methodology; Triazine Coupling