Table 2.

Buoyant density measurements of RBC plasma membranes

Sample	Density, g/cm3
RBC open ghost plasma membrane	1.15 ± 0.004
Fully shaved RBC plasma membrane (Dmembrane)	1.081 ± 0.006
Lipid-extracted membrane protein from fully shaved RBC plasma membranes (Dprotein)	1.281 ± 0.003
Total membrane lipid from RBC open ghost plasma membranes	1.022 ± 0.004
Total membrane lipid from fully shaved RBC plasma membranes (Dlipid)	1.022 ± 0.004

Buoyant density measurements for RBC open ghost plasma membranes, fully shaved RBC plasma membranes, lipid-extracted membrane protein from fully shaved RBC plasma membranes, total membrane lipid from RBC open ghost plasma membranes, and total membrane lipid from fully shaved RBC plasma membranes were determined by using standard methods. All buoyant density measurements were repeated a total of 60 times for each of the five different types of samples.