Next, we investigate the effect of concentration on the flow response of PII-2T/CB and PII-2T/CB/DMF aggregates. First, we characterized the viscosity of the small amounts of PII-2T/CB solution available using a method where a droplet is drawn into a microfluidic capillary and the position and velocity of the free-surface is tracked as it flows in . The specific viscosity versus concentration is shown for PII-2T in CB in Figure (the corresponding viscosity of CB/DMF solutions could not be measured reliably due to agglomerates approaching a size comparable to the capillary). At around 10 mg/mL, the concentration scaling exponent changes from of 1 to 1.7. The intrinsic viscosity of the solution can also be determined from the slope of vs in the linear regime using the relation , which yields a value of = 0.11 mL/mg. This gives another estimation of the overlap concentration which yields a value of 9 mg/mL and is in agreement with the transition between the scaling regimes.