Final GFP protein purity, concentration, and comparison to crude lysate using microfluidic capillary electrophoresis.

<p><i>A</i>, Electropherogram of 10–150 kDa molecular weight standards. The <i>numbers</i> indicate the molecular weight of each standard protein peak expressed in kDa. These numbers are aligned at the top of panels B and C and indicate molecular weights observed in those samples as well. <i>B</i>, Electropherogram of the GFP-containing bacterial lysate, which served as the initial sample load used for HIC column scouting. <i>C,</i> Electropherogram of the concentrated GFP-containing SEC fractions 84–88, the final product of the purification scheme. Fluorescence intensity expressed in relative units (<i>RU</i>). <i>Panel insets</i>, Virtual gels generated from electropherogram data. <i>Arrows</i>, theoretical molecular weight of GFP. <i>LIS</i>, low MW internal standard; <i>HIS</i>, high MW internal standard; <i>SP</i>, system peaks generated by the electrophoresis system unrelated to the sample being assayed.