Characterization of albumin microspheres by sedimentation field-flow fractionation.

Sedimentation field-flow fractionation (FFF) is a new technique that separates and characterizes submicron particles. In the present work, two independent sedimentation FFF methods are presented to characterize bovine serum albumin microspheres in terms of particle size, polydispersity, and diffusion coefficient. Particle diameters and polydispersities determined by the two sedimentation FFF methods were in excellent agreement with each other and in good agreement with values calculated from transmission electron microscopy (TEM) measurements. The diameters calculated from the two FFF methods and TEM were 0.349, 0.346, and 0.354 microgram, respectively.