Short-Time Glassy Dynamics in Viscous Protein Solutions with Competing Interactions

Dynamic properties of different liquid states in systems with competing interactions studied with lysozyme solutions

“…Note that the final results of interaction potentials of lysozyme samples were reported briefly in the ESI † of our previous papers. 15,19 Here, for the completeness of the discussion, we first provide the missing details in the previous papers about the experimental procedure and the analysis method together with the simulation results to verify our analysis method. The SANS data of the investigated lysozyme samples, prepared as discussed in the Methods section, span concentrations from 10 to 480 mg mL À1 at temperatures ranging from 5 1C to 50 1C.…”

“…As shown in the ESI, † the normalized Fig. 1 (a) Inter-particle structure factors obtained from normalizing SANS data (black, open symbols, replotted from a prior publications 15,19 ) with best fits using IET (lines, replotted from a prior study 19 ) and calculations from MC simulations (colored, filled symbols). All data points at 5 1C and 25 1C are shifted vertically for clarity.…”

“…Viscosity data in (b) are replotted form an earlier publication. 15 The colored dotted lines in (a and b) are fits to extrapolate glass and gel transitions, respectively. (c) A plot of the ratio of short-time dynamics to the effective long-time dynamics (represented by the inverse of Z r0 ) of lysozyme (symbols) relative to hard sphere expectations (solid line).…”

“…13,14 By systematically studying the short time dynamics and the rheological properties of lysozyme protein solutions at low salt conditions, it has been shown that the normalized short time dynamics at high concentrations can be as slow as the dynamics of many colloidal systems in glassy states despite the fact that the studied lysozyme samples remain in liquid states. 15 The formation of intermediate range order (IRO) has been shown to be the driving force for this slow dynamics. 15 It is worth pointing out that the formation of IRO, driven by the competition of the short-range attraction and long-range repulsion, is one of the hallmark structural features of SALR systems.…”

“…15 The formation of intermediate range order (IRO) has been shown to be the driving force for this slow dynamics. 15 It is worth pointing out that the formation of IRO, driven by the competition of the short-range attraction and long-range repulsion, is one of the hallmark structural features of SALR systems. IRO can be experimentally determined by observing a scattering peak in the inter-particle structure factor at a wave vector much smaller than that of the nearest neighbour scattering peak.…”