A Microliter Capillary Rheometer for Characterization of Protein Solutions

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

“…The range of shear rates (10s −1 <γ < 10 5 s −1 ) varied for each sample due to the variation in the sample viscosity and limits of pressure drop supplied. [28] Regardless, all data sets are well within the zero-shear limit of P e = 3πη s σ 3γ /4k B T << 1, where η s is the solvent viscosity and σ = 30.7Å is the particle diameter. The highest P e number (at low concentrations) only approached P e ≈ 2x10 −3 .…”

“…[27] Hence, even though samples at 480 mg/mL can form crystals after long incubation periods, the long-ranged repulsion stabilizes the protein during all of our experiments. Viscosity is determined using a microcapillary viscometer [28] to avoid air-water interfacial effects. [29] Lysozyme solution structures and shorttime dynamics are characterized using small angle neutron scattering (SANS) and neutron spin echo (NSE), respectively, performed at the Institut Laue-Langevin in Grenoble, France and the NIST Center for Neutron Research in Gaithersburg, MD, USA.…”

The molecular basis of high viscosity of monoclonal antibodies (mAbs) at high concentration

“…Recently a rheometer has been developed that uses pressure drop measurements to determine viscosity (Hudson, Sarangapani, Pathak, & Migler, 2014;Pipe & McKinley, 2009). This rheometer generally can meet the need to use small microliter volumes of material, has a wide dynamic range of shear rates (range of ∼3 decades), and no air-sample interface, which has been shown to be a potential problem in conventional rotational viscometers (Patapoff & Esue, 2009).…”

“…This rheometer generally can meet the need to use small microliter volumes of material, has a wide dynamic range of shear rates (range of ∼3 decades), and no air-sample interface, which has been shown to be a potential problem in conventional rotational viscometers (Patapoff & Esue, 2009). This instrument has an uncertainty of only a few percent and its performance was evaluated using monoclonal antibody solutions at different concentrations, pH, and temperature (Hudson et al, 2014).…”

Parallel temperature-dependent microrheological measurements in a microfluidic chip

“…This advantage has been demonstrated in a "phase chip" used to map the phase diagram of protein nucleation and crystallization, [19][20][21][22][23] a microfluidic viscometer with an embedded fluid temperature controller, 24 and a single-sample microcapillary rheometer. 25 Rapid temperature control of a microfluidic device capable of holding multiple samples would leverage the advantages of these technologies.…”