Preparative‐scale isoelectric trapping by recursive electrophoresis in a compartmentalized system having orthogonal primary and secondary pH gradients. Part 1 – Construction and standard operation

Abstract

The performance of the current preparative-scale isoelectric trapping systems is limited by the serial arrangement of the separation compartments. A new system has been developed that achieves trapping by recursive electrophoresis in a compartmentalized system (T-RECS). T-RECS features (i) parallel-connected elementary separation heads with independent electrode compartments, feed compartments, and harvest compartments, (ii) orthogonal primary pH gradients and secondary pH gradients, (iii) directionally controlled convective analyte transport along the primary (resolving) pH gradients, and (iv) electrophoretic analyte transport along the secondary (harvesting) pH gradients. The operation of T-RECS has been quantitatively characterized via separation of small molecule ampholytes.

Preparative‐scale isoelectric trapping by recursive electrophoresis in a compartmentalized system having orthogonal primary and secondary pH gradients. Part 2 – Operation in cascade mode

“…Since the companion paper, Part 1 [1], describes T-RECS, its set-up, and the chemicals used for the IET separations, they are not repeated here. Figure 1 shows the schematic of T-RECS set up to operate as a cascade of binary separations.…”

“…Part 1 of this paper (see the preceding companion paper, [1]) described the design, manufacture, and standard mode of operation of a new isoelectric trapping (IET) device, trapping by recursive electrophoresis in a compartmentalized system (T-RECS).…”

“…Recently, IET systems that utilize parallel arrangement of the compartments were developed [1,[14][15][16][17][18][19]] to permit an increase in the number of fractions collected without a decrease in the electric field strength in those compartments. Both the dPC TM Fractionator [14][15][16] and the ConFrac [17][18][19] were designed for analytical-scale IET separations.…”

“…Both the dPC TM Fractionator [14][15][16] and the ConFrac [17][18][19] were designed for analytical-scale IET separations. T-RECS [1], on the other hand, was intended to implement the principles of parallel MCEs in a preparativescale unit. The design, manufacture, and initial testing of T-RECS are described in detail in [1].…”

“…T-RECS [1], on the other hand, was intended to implement the principles of parallel MCEs in a preparativescale unit. The design, manufacture, and initial testing of T-RECS are described in detail in [1]. T-RECS features (i) parallel-connected elementary separation heads with independent electrode compartments, feed compartments, and collection compartments, (ii) orthogonal primary and secondary pH gradients, (iii) directionally controlled convective analyte transport along the primary (resolving) pH gradients, and (iv) electrophoretic analyte transport along the secondary (harvesting) pH gradients.…”