Agarose and polyacrylamide gel electrophoresis of ascidians and mammalian dermatan sulfate. A, purified dermatan sulfate (~15 mg) from S. plicata, H. pallida, P. nigra or C. intestinalis were applied to a 0.5% agarose gel and run for 1 h at 100 V in 0.05 M 1,3-diaminopropane/acetate (pH 9.0). Glycosaminoglycans were fixed with 0.1% N-cetyl-N,N,N-trimethylammonium bromide solution. After 12 h, the gel was dried and stained with 0.1% toluidine blue in acetic acid/ethanol/water (0.1:5:5, v/v). To a standard, a mixture of mammalian glycosaminoglycans containing 10 mg each of chondroitin 4-sulfate (CS), dermatan sulfate (DS) and heparin (Hep) were applied in agarose gel. B, purified dermatan sulfate (~15 mg) from S. plicata, H. pallida, P. nigra or C. intestinalis were applied to 6% 1-mm-thick polyacrylamide gel slab in 0.02 M sodium barbital (pH 8.6) and run for 30 min at 100 V. After electrophoresis the dermatan sulfates were stained with 0.1% toluidine blue in 1% acetic acid and then washed for about 4 h in 1% acetic acid. The molecular mass (M.W.) markers were high molecular mass dextran sulfate (S1, ~500 kDa), chondroitin 6-sulfate (S2, ~54 kDa), chondroitin 4-sulfate (S3, ~36 kDa) and low molecular mass dextran sulfate (S4, ~8 kDa).