How far have we progressed toward automated electrophoresis in sieving media of the twenty-first century?

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Abstract
The automation of electrophoresis in polymeric sieving media requires (i) an objective definition of the conditions (the polymer, its concentration, solvent, buffer, pH, ionic strength, temperature) under which a particular separation proceeds most effectively; (ii) apparatus capable of zone detection, acquisition by computer, evaluation (migration distance, zone width and area) and a printout of the number of components, their size and net charge, and the polymer conditions under which each component separates most effectively from its two neighboring zones. Both of these prerequisites of automation have been met to a first approximation at this time and, after further maturation, assembly and streamlining should be able to fill the need of the coming century for a more efficient, nonarbitrary and cost‐effective mode of macromolecular and cellular particle separation. (i) The realization of the qualitative equilivalence of polymer solutions and gels had greatly increased our options in the choice of sieving media. That choice can be made objectively by correlating separation efficiency (S), particle size (R) and intrinsic viscosity (ηo) of the polymer. (S) is a function of the slope, KR (R), of the Ferguson plot [log(mobility) vs. polymer concentration], or with nonlinear plots (DNA, agarose) KR(R,T). KR is at present most easily derived from transverse pore gradient gels or by conducting capillary zone electrophoresis (CZE) at multiple polymer concentrations. Pore gradient CZE appears promising. CZE also defines the free mobility unequivocally. Computer programs exist to generate KR from migration distances (times), and optimal S and polymer concentration for a particular R from KR. Optimal S can be related objectively with ηo to define, as a first‐order approximation, the optimal polymer for the separation within a narrow R‐range. (ii) Apparatus with automated detection of zones and acquisition of migration distances has become commercially available (e.g. Applied Biosystems, Du Pont, LabIntelligence). One of these scans multiple lanes and can be interfaced to compute KR and S. Thus, all elements necessary for automated electrophoretic separation under optimally effective separation conditions are available in rudimentary form. Their development, assembly, integration and streamlining should be feasible prior to the onset of the next century.