PMC:2728246 / 8086-9371 JSONTXT

{"project":"2_test","denotations":[{"id":"19652920-15584763-56190941","span":{"begin":110,"end":114},"obj":"15584763"}],"text":"Sample for dataset 12: A 7% positively charged gel sample was prepared according to (Cierpicki and Bushweller 2004). A stock solution of 40% acrylamide and N,N′-methylenebisacrylamide in a 19:1 ratio was mixed 1:1 with a stock solution of 40% (3-acrylamidopropyl)-trimethylammonium chloride (APTMAC) and N,N′-methylenbisacrylamide in a 19:1 ratio. The mixtures were diluted with 10× TBE buffer (0.9 M TRIS, 0.9 M borate, 0.02 M EDTA, pH = 8.2) to a final concentration of 7%. Polymerization was initiated by the addition of 0.15% ammonium peroxide sulphate and 1% tetramethylethylenediamine. Polymerization of the mixture was carried out overnight in plastic tubes of 3.5 mm in diameter. Gels were extensively washed in deionized water where they swelled significantly to a diameter of 8 mm. Gels were then cut to 4 cm in length to match a ratio between length and diameter of 5:1. Gels were dried for several days on a plastic support wrapped with polyvinylidene chloride foil. To prepare the sample, the dried gel was transferred to a 5-mm microcell tube (Shigemi Inc., Allison Park, PA), ~2 mg of protein were dissolved in 300 μl of buffer (50 mM NaPO4, 100 mM NaCl, pH 6.5, 0.05% NaN3) and added to the gel. The plunger was positioned to limit the final length of the gel to 12 mm."}