title: Exploring the molecular basis for the metal-mediated assembly of alginate gels.
abstract: The binding of sodium and calcium ions to single and multiple poly-G decamer strands has been modelled by conducting a series of molecular dynamics simulations. Implications for metal mediated inter-strand interactions and gel assembly have been explored by systematically introducing up to three strands into each of these simulations. A particular emphasis has been placed on revealing intrinsic binding modes by an unbiased initial positioning of the metal ions. The results have revealed binding modes that provide a rationale for the observed gelling of alginate by calcium rather than sodium ions. A number of junction zones involving calcium ions have been identified that result in chain aggregation. This includes a distinctive perpendicular motif that appears to be ubiquitous in previously reported AFM images of open 3-D alginate networks. The coordination geometries of the metal ions have been characterised and the metal-mediated junctions between associated strands are described in detail.
authors: Institute for Sustainability and Innovation (ISI), Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia; College of Engineering and Science, Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia. Electronic address: Matthew.Stewart@vu.edu.au.
authors: Matthew B
authors: MB
authors: Stewart
authors: Institute for Sustainability and Innovation (ISI), Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia; College of Engineering and Science, Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia. Electronic address: Stephen.Gray@vu.edu.au.
authors: Stephen R
authors: SR
authors: Gray
authors: Institute for Sustainability and Innovation (ISI), Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia; College of Health and Biomedicine, Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia. Electronic address: Todor.Vasiljevic@vu.edu.au.
authors: Todor
authors: T
authors: Vasiljevic
authors: Institute for Sustainability and Innovation (ISI), Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia; College of Engineering and Science, Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia. Electronic address: John.Orbell@vu.edu.au.
authors: John D
authors: JD
authors: Orbell
keywords: Alginate gels; Calcium coordination; Molecular dynamics; Sodium alginate