Carousel microparticle separating, washing and reading device and method of use

Claim 1

A microparticle separating, washing and reading device wherein microparticles are separated from a sample-immunoassay mixture, washed by one solution and then passed into a reading area wherein the microparticles may be reacted with a substrate solution, said device comprising: a) a substantially circular carousel having a center and a plurality of radially dispersed chambers, said chambers having a closed end distal to the center and an open end proximal to the center for communicating with a feed area disposed substantially at the center, said carousel adapted for rotation about its center by a centrifuge; b) barrier means, disposed substantially perpendicular to the radius of the carousel within said chambers and communicating with the walls of the chamber, for stabilizing the solutions; and c) sample holder means, adapted for placement substantially at the center, for containing the microsphere sample-immunoassay mixture and dispensing the mixture to the chambers when sufficient centrifugal force is applied.

Claim 5

A method for separating, washing and detecting microparticles employed in an immunoassay for determining the presence of an immunological determinant in a sample comprising the steps of: providing a substantially circular carousel having a center and a plurality of radially dispersed chambers with closed ends distal to the center of the carousel and open ends proximal to the center of the carousel for communicating with a feed area disposed substantially at the center, said carousel adapted for rotation about its center by a centrifuge; rotating the carousel; adding to said feed area a substrate solution whereby the substrate solution is substantially evenly dispersed among the chambers and flows to the distal ends; further adding to said feed area a wash solution having a density at the maximum equal to that of the substrate whereby a wash layer is formed in the chambers intermediate the substrate and the proximal end; reacting the sample with microparticles coated with an immunological counterpart to the determinant to be assayed under conditions appropriate for an immunological reaction to form activated microparticles, said sample without microparticles having a density not more than that of the wash solution and said microparticles having a density at least equal to the substrate solution; introducing the reacted sample and microparticles to the feed area; subjecting the microparticles in the sample to appropriate centrifugal force whereby a third layer is formed in the chambers intermediate the wash solution and the proximal end and the microparticles are caused to move through the wash solution and into the substrate solution; and measuring the presence of activated microparticles for qnantitating the presence of the immunological determinant in the sample.

Claim 6

A method for separating, washing and detecting microparticles employed in an immunoassay for determining the presence of an immunological determinant in a sample comprising the steps of: providing a substantially circular carousel having a center and a plurality of radially dispersed chambers with closed ends distal to the center of the carousel and open ends proximal to the center of the carousel for communicating with a feed area disposed substantially at the center, said carousel adapted for rotation about its center by a centrifuge; rotating the carousel; adding to said feed area a substrate solution whereby the substrate solution is substantially evenly dispersed among the chambers and flows to the distal ends; further adding to said feed area a wash solution having a density at the maximum equal to that of the substrate whereby a wash layer is formed in the chambers intermediate the substrate and the proximal end; reacting the sample with microparticles coated with an immunological counterpart to the determinant to be assayed under conditions appropriate for an immunological reaction to form activated microparticles, said sample without microparticles having a density not more than that of the wash solution and said microparticles having a density at least equal to the substrate solution; introducing the reacted sample and microparticles to the feed area; subjecting the microparticles in the sample to appropriate centrifugal force whereby a third layer is formed in the chambers intermediate the wash solution and the proximal end and the microparticles are caused to move through the wash solution and into the substrate solution; and measuring the presence of activated microparticles for qnantitating the presence of the immunological determinant in the sample.

Claim 11

A method for separating, washing and detecting labeled particles from a determinant containing sample-reagent immunoassay mixture comprising the steps of: a) providing a carousel comprising a plurality of radially dispersed chambers having at the ends distal to the center at least one optical window, and at least one port in said chamber distal to the optical window for adding fluids to said chamber, said chamber further adapted to promote layering of said fluids when rotated; b) adding to said carousel a wash solution having a density at least equal to that of the sample reagent mixture but less than that of the particles to be separated; c) rotating said carousel to force the wash solution, by centrifugal force, to the end of the chamber distal from the center of the carousel; d) adding to said chamber a sample-reagent mixture containing particles to be detected so that while the carousel is being rotated sample reagent and wash layers are formed; e) further rotating said carousel about its center under conditions sufficient to move the particles to be detected through the wash solution to the optical window area; and f) detecting labeled particles whereby the presence or absence of a determinant within the sample may be correlated.

Claim 12

A method for separating, washing and detecting labeled particles from a determinant containing sample-reagent immunoassay mixture comprising the steps of: a) providing a carousel comprising a plurality of radially dispersed chambers having at the ends distal to the center at least one optical window, and at least one port in said chamber distal to the optical window for adding fluids to said chamber, said chamber further adapted to promote layering of said fluids when rotated; b) adding to said carousel a wash solution having a density at least equal to that of the sample reagent mixture but less than that of the particles to be separated; c) rotating said carousel to force the wash solution, by centrifugal force, to the end of the chamber distal from the center of the carousel; d) adding to said chamber a sample-reagent mixture containing particles to be detected so that while the carousel is being rotated sample reagent and wash layers are formed; e) further rotating said carousel about its center under conditions sufficient to move the particles to be detected through the wash solution to the optical window area; and f) detecting labeled particles whereby the presence or absence of a determinant within the sample may be correlated.