US 7,255,895 B2 · Method for controlling solute loading of polymer microparticles

Abstract

Solute-loaded polymer microparticles are obtained by immersing microparticles in a bath comprising a selected solute dissolved in a ternary solvent system. A first solvent of the ternary system is a strong solvent for both the solute and the polymer from which the microparticle was formed. A second solvent is a weak solvent or non-solvent for the solute and the polymer (tuning solvent). A third solvent is a weak solvent or non-solvent for the solute and polymer, but serves as a co-solvent with respect to the first and second solvents in that it is miscible with both the first and second solvents. The amount of solute incorporated into the microparticles is controlled by adjusting the ratio of solute with respect to the microparticle polymer, and by adjusting the composition of the ternary solvent system, principally the amount of tuning solvent. The method is particularly useful for providing libraries of combinatorially encoded microparticles containing distinguishable dye loadings, particularly distinguishable fluorescent dye loadings.

Claims29

Dependent claims

A method for generating a plurality of microparticle populations of different dye concentrations wherein dye is loaded into polymer microparticles to generate said microparticle populations, comprising:

(a) providing:
(i) at least one first solvent in which the dye and the microparticle polymer are soluble;
(ii) at least one tuning solvent in which the dye and the microparticle polymer are not or only weakly soluble, said first and tuning solvents being immiscible or at most partially miscible;
(iii) at least one third solvent in which the dye and the microparticle polymer are not or only weakly soluble, said third solvent being miscible with the first and tuning solvents;
(b) forming a plurality of suspensions of said polymer microparticles, each in a designated volume of a mixture including the tuning solvent and the third solvent;
(c) adding to said polymer microparticle suspension a solution including the dye dissolved in said first solvent to form a homogeneous solution in the mixture of the first, tuning and third solvents;
and
(d) increasing the uptake of dye into the polymer microparticles in at least one of said populations relative to another of said populations by decreasing the solvency of the mixture of the first, tuning and third solvents for the dye.

5 more elements

A method of producing dyed polymer microparticles comprising:

(a) providing:
(i) at least one first solvent in which the dye and the microparticle polymer are soluble;
(ii) at least one tuning solvent in which the dye and the microparticle polymer are not or only weakly soluble, said first and tuning solvents being immiscible or at, most partially miscible;
(iii) at least one third solvent in which the dye and the microparticle polymer are not or only weakly soluble, said third solvent being miscible with the first and tuning solvents;
(b) forming a suspension of said polymer microparticles in a designated volume of a mixture comprising at least one tuning solvent and at least one third solvent;
(c) adding to said polymer microparticle suspension a solution comprising the dye dissolved in said first solvent whereby the dye is taken up by the microparticles to provide a master-batch suspension of microparticles characterized by a first concentration of said dye in the microparticles;
(d) creating two or more aliquots from said microparticle master-batch suspension containing selected added amounts of tuning solvent, wherein the added tuning solvent increases the amount of dye partitioning to the polymer microparticles in said aliquots;
and
(e) incubating the polymer microparticle suspension aliquots for a period of time so that the amount of dye partitioning to the microparticles, for a given initial dye concentration in the dye solution, is controlled by the amount of tuning solvent added to the microparticle suspension aliquots.

6 more elements

Dependencies are inferred from the claim text.

Method for controlling solute loading of polymer microparticles

Life of this patent

Method for controlling solute loading of polymer microparticles

Life of this patent

Abstract

Claims29