title: Application of the Kwei equation to model the Tg behavior of binary blends of sugars and salts.
abstract: Vitrification of sugar-based solutions plays an important role in cryopreservation, lyophilization, and the emerging field of anhydrous preservation. An understanding of the glass transition characteristics of such formulations is essential for determining an appropriate storage temperature to ensure an extended shelf life of vitrified products. To better understand the effect of salts on the glass transition temperature (T(g)) of glass-forming sugars, we investigated several data-fitting models (Fox, Gordon-Taylor and Kwei) for sugar-salt formulations using data from the literature, as well as new data generated on blends of trehalose and choline dihydrogen phosphate (CDHP). CDHP has recently been shown to have promise as a stabilizing agent for proteins and DNA. The Kwei equation, which has a specific parameter characterizing intermolecular interactions, provides good fits to the T(g) data for sugar-salt blends, and complements other commonly used models that are frequently used to model T(g) data.
authors.affiliation: Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
authors.forename: Lindong
authors.initials: L
authors.lastname: Weng
authors.affiliation: School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Ranganathan
authors.initials: R
authors.lastname: Vijayaraghavan
authors.affiliation: School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Macfarlane
authors.affiliation: Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA. Electronic address: gdelliot@uncc.edu.
authors.forename: Gloria D
authors.initials: GD
authors.lastname: Elliott
mesh_terms: D000818:Animals; D002951:Citrates / Q000737:chemistry; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000737:chemistry*; D005612:Freeze Drying; D006801:Humans; D007700:Kinetics; D015233:Models, Statistical; D010767:Phosphorylcholine / Q000737:chemistry*; D012492:Salts / Q000737:chemistry*; D012996:Solutions; D013395:Sucrose / Q000737:chemistry; D014199:Trehalose / Q000737:chemistry*; D014325:Tromethamine / Q000737:chemistry; D058989:Vitrification
chemical_list: D002951:Citrates; D003451:Cryoprotective Agents; D012492:Salts; D012996:Solutions; D014325:Tromethamine; D010767:Phosphorylcholine; D013395:Sucrose; D014199:Trehalose
keywords: Anhydrous preservation; Choline dihydrogen phosphate; Cryoprotectant; Fox; Glass transition temperature; Gordon–Taylor; Kwei; Trehalose