title: Investigation of the hydration of nonfouling material poly(sulfobetaine methacrylate) by low-field nuclear magnetic resonance.
abstract: The strong surface hydration layer of nonfouling materials plays a key role in their resistance to nonspecific protein adsorption. Poly(sulfobetaine methacrylate) (polySBMA) is an effective material that can resist nonspecific protein adsorption and cell adhesion. About eight water molecules are tightly bound with one sulfobetaine (SB) unit, and additional water molecules over 8:1 ratio mainly swell the polySBMA matrix, which is obtained through the measurement of T(2) relaxation time by low-field nuclear magnetic resonance (LF-NMR). This result was also supported by the endothermic behavior of water/polySBMA mixtures measured by differential scanning calorimetry (DSC). Furthermore, by comparing both results of polySBMA and poly(ethylene glycol) (PEG), it is found that (1) the hydrated water molecules on the SB unit are more tightly bound than on the ethylene glycol (EG) unit before saturation, and (2) the additional water molecules after forming the hydration layer in polySBMA solutions show higher freedom than those in PEG. These results might illustrate the reason for higher resistance of zwitterionic materials to nonspecific protein adsorptions compared to that of PEGs.
authors.affiliation: State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027.
authors.forename: Jiang
authors.initials: J
authors.lastname: Wu
authors.forename: Weifeng
authors.initials: W
authors.lastname: Lin
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.forename: Shengfu
authors.initials: S
authors.lastname: Chen
authors.forename: Yung
authors.initials: Y
authors.lastname: Chang
mesh_terms: D001622:Betaine / Q000031:analogs & derivatives / Q000737:chemistry; D002151:Calorimetry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008689:Methacrylates / Q000737:chemistry*; D015394:Molecular Structure
chemical_list: D008689:Methacrylates; C521589:sulfobetaine methacrylate polymer; D001622:Betaine; C483727:sulfobetaine