Molecular Weight: Measurements with Gravity Cells

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Science  01 Mar 1963:
Vol. 139, Issue 3557, pp. 837-838
DOI: 10.1126/science.139.3557.837


A gravity cell can be used to determine the weights of particles greater than 108 molecular weight units. The solution is maintained at a temperature which is constant to ± 0.001°C until equilibrium between sedimentation produced by gravity is balanced by back diffusion. The weight-average molecular (particle) weight of tipula iridescent virus was (1.05 ± 0.02) x 109.