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This paper demonstrates the use of UV-transparent replaceable polymer networks for the separation of SDS-protein complexes on the basis of molecular weight. First, the use of linear (i.e. non-cross-linked) polyacrylamide is shown to provide molecular separation of SDS-protein complexes. A study reveals such columns to yield significantly greater lifetime than cross-linked gels because of the flexibility of the noncovalently attached polymer chains. However, column lifetime was still found to be limited (approximately 20-40 injections), and detection at 214 nm was problematical because of the absorbance of polyacrylamide. UV-transparent polymer networks of dextran and PEG were substituted for polyacrylamide with successful molecular weight sieving of SDS-protein complexes at 214 nm. Due to their low to moderate viscosities, these networks could be routinely replaced leading to the possibility of hundreds of injections with a single column. Migration time reproducibilities of 0.5% RSD or less were found with replacement of the network. Using dextran, calibration plots of peak area vs concentration of standard protein were linear over the range of 0.5 microgram/mL up to at least 0.25 mg/mL. Furthermore, plasma samples could be directly utilized because of the strong solvating power of SDS. Rapid separation of protein mixtures are demonstrated with these UV-transparent polymer networks.

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Picomole amounts of oligodeoxynucleotides [polydeoxyadenylic acids, (dA)4&..s] were baseline resolved and analyzed in <8 min by high-performance capillary electrophoresis with polyacrylamide gels. In addition, fast analysis of a crude 70-mer oligodeoxynucleotide and a slab gel-purified 99-mer oligodeoxynucleotide was accomplished, demonstrating the ability of high-performance capillary electrophoresis to characterize rapidly synthesized oligonucleotides. Besides analytical separations, 800 ng of a primer (20-mer) was isolated in <20 min. The purified species was collected in water and subsequently used as a probe in a standard dot-blot analysis. The use of high-performance capillary electrophoresis for the analysis and purification of a variety of biopolymers is simple, rapid, and has the potential for automation. (7), was used at a wavelength of 260 nm. The tubing and the detector were cooled with a thermostated air bath. The power supply outlets were connected to platinum electrodes, 5, immersed in buffer reservoirs, 6 (for analytical runs), or in a microcentrifuge vial, 7 (for collection). An analog/digital interface, 8 (Nelson, Cupertino, CA), attached to a recorder, 9, and IBM PC/XT, 10, were used to record the results and process the data.Materials. The oligodeoxynucleotide (5' GCCACGTCCA-GATTTATCAG 3') in Fig. 4 was synthesized on a model 380A DNA synthesizer (Applied Biosystems, Foster City, CA) using the silica-based solid-phase method (8) and the proton-activated nucleoside phosphoramidate method with methoxyphosphoramidates (9). The side-chain protecting groups were liberated by treatment with ammonium hydroxide at 550C for 6 hr. After this step, the oligodeoxynucleotide was recovered by lyophilization and dissolved in water.Polydeoxyadenylic acid mixture (dA)40-60 was purchased from Pharmacia. The crude 70-mer and slab gel-purified 99-mer oligodeoxynucleotides were the gift of N. Bischoffer (Genentech, South San Francisco, CA Procedure. A modified version (10) of the polyacrylamide gel capillary column described in ref. 5 was filled with polyacrylamide gel (T = 7.5%, C = 3.3%) (11) in 7 M urea/0.1 mM Tris/0.25 mM borate, pH 8.3. The field applied to the gel was 400 V/cm. To remove impurities from the acrylamide gel, the capillary gel column was preelectrolyzed at 6 kV for 30-60 min. During electrophoresis, the capillary was maintained at room temperature. The samples were electrophoretically injected into the column by dipping the cathodic end of the capillary into an aqueous solution of the sample and applying a field of 400 V/cm for =10 sec.Abbreviations: HPCE, high-performance capillary electrophoresis. ITo whom reprint requests should be addressed. 9660The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

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