Separation of monodisperse poly(3-hydroxybutyrate) particles by fractionation: Theory and practice

Abstract

A new method is proposed in this article which is based on fractionation and results poly(3-hydroxybutyrate) particles of nearly monodisperse size distribution. This kind of separation is achieved by taking advantage of the phenomenon that the movement of particles triggered by a constant force in a homogeneous fluid have a velocity depending on the diameter of the particle. The procedure consists of two steps. First, a set of particles with a wide distribution of diameters is produced by using the emulsion-suspension method followed by their separation into fractions on hydrogel columns in the second step. The novel concept of statistical filters has been introduced in order to describe this phenomenon quantitatively. Additionally, mathematical models have been developed that allow the simulation and prediction of the outcome of particle separation. Our method was verified by model calculations and measurements; the results of the two approaches correlated closely. The proposed method is very advantageous for the preparation of drug carrier matrices, because it allows the close control and modeling of the kinetics of drug release.