Analysis of αB-crystallin polydispersity in solution through native microfluidic electrophoresis

Maya A. Wright,Francesco Simone Ruggeri, Kadi L. Saar, Pavan K. Challa, Justin L. P. Beneschc  and  Tuomas P. J. Knowles

Analyst, 2019,144, 4413-4424

In this paper, the authors utilise microfluidic diffusional sizing and electrophoresis to characterise the oligomeric states of the chaperone protein alphaB-crystallin. The MDS and electrophoresis measurements confirm that both wild-type and truncated variants of alphaB-crystallin have different degrees of oligomerisation in the solution phase. In addition, insights into the distribution and specific species present in heterogeneous alphaB-crystallin mixtures could be obtained by combining electrophoresis data with spectroscopic analysis techniques.

wright et al fig 2

Fig. 2 The high-field electrophoresis device. Schematic of the device. Electrolyte solution (yellow) is infused into the device via syringes and pumps, while sample and carrier medium stored in gel loading tips are introduced by withdrawing from the outlets using a flow splitter. A voltage is applied at the outlets and is carried into the device via the electrolyte solution (yellow), resulting in an electric field being applied across the main channel. Deflection of the analyte is imaged at the position highlighted by the orange square. The image in the orange square corresponds to BSA at 1 mg mL−1. The image in the green square is a close up the electrolyte channels filled with 3 M KCl plus BSA 2 mg mL−1 for visualisation.

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