The sedimentation coefficient of a certain DNA in 1M NaCl at 20C was measured by boundary sedimentation at 24,630 rpm. The following data were recorded:
Time Distance x of boundary from center (cm)
16 6.269
32 6.351
48 6.438
64 6.517
80 6.605
96 6.681
a) Plot log x vs time and calculate the sedimentation coefficient
b) The partial specific volume of the sodium salt of DNA is 0.556 cm3/g. The viscosity and density of the 1M NaCl solution and of water are 1.104 cP, 1.04 g/cm3 and 1.005 cP, respectively. Calculate s20,w for the DNA