Polyacrylamide-Agarose Gels

Fig. 7.4. a) Molecular weight-mobility relationships for electrophoresis of RNA in composite polyacrylamide-agarose gels of the stated acrylamide concentration (%) (adapted from Peacock and Dingraan 1968). b) Dependence of mobility on gel concentration for single-stranded (dotted lines), and double-helical (rod-like) RNAs (full lines) (Fisher and Dingman 1971). 

SDS, preferably directly into the scintillation vials. Then the vials are shaken with 10 ml of Instagel emulsifier (scintillant Packard) for 3-5 h at 37°C and counted. Efficiency is 7% for and 33% for C. Alternatively the radioactive materials can be solubilized and thus liberated from the electrophoretic support. This can be materialized by, e.g., Bio-Solv BBS-3 (Beckman Instruments, acidic surfactant). The scintillation solution used is composed of 4 g PPO, 0.2 g POPOP, 170 ml Bio-Solv-BBS 3, 60 ml of water, and 770 ml of toluene [242]. Another solubilizer that can be applied is NCS (Nuclear Chicago Solubilizer) with this solubilizer the polyacrylamide or polyacrylamide-agarose gel slices have to be incubated at 65°C for 2 h. Tritiated ribonucleic acid fractions can be solubilized with 10% piperidine at 60°C. Gel slices are incubated in the scintillating vials with the solubilizer for several hours, allowed to dry, dissolved in distilled water (the gel actually swells at this stage), covered with water miscible toluene scintillation fluid and counted. 

Examination of liver N-acetyltransferase obtained from rapid acetyla-tor rabbits on polyacrylamide-agarose gel electrophoresis has shown that two anodal migrating components with enzymic activity are regularly present (Szabadi, 1970). The slower migrating component accounts fdr most of the activity (ca. 67-83%). Both components possess sulfamethazine and p-aminobenzoic acid acetylating activity. Preliminary comparative studies of the electrophoretic patterns for rapid and slow acetylator rabbits have also been carried out. These studies, which are described in Section III,D, provide some clues about the possible nature of each of these electrophoretic components. 

Boorsma, D. M. and Streefkerk, J. G. 1976. Peroxidase-conjugate chromatography isolation of conjugates prepared with glutaraldehyde or periodate using polyacrylamide-agarose gel. J. Histochem Cytochem., 24,481-6. 

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