2.2.3. Permeation denaturant through microchannels
Using the prepared microchannels, the denaturant (GdnHCl) solution was dialyzed, in order to confirm whether the denaturant concentration could be reduced to the desired concentration within a predetermined residence time, τ .
Using a syringe pump, c f0 = 5 mol/L GdnHCl solution was fed from the inlet of the feed-side channel, and pure water (c p0 = 0 mol/L) was fed from the inlet of the permeation side channel at v p = 0.5 mL/min. The flow rate of the GdnHCl solution on the feed side was changed fromv f = 0.1 mL/min (retention time τ = 10 min), 0.05 mL/min (τ = 20 min), to 0.033 mL/min (τ = 30 min). The feed flow rate was changed at dialysis time t = 50, 150 minutes. The solutions were collected from the outlets of the feed-side channel and the permeate side channel, and the absorbances were measured using a UV-vis spectrophotometer, to determine the GdnHCl concentration.