US 4,726,904 A · Apparatus and method for the analysis and separation of macroions

Abstract

An apparatus for the separation of macroion groups from a mixture utilizing a three field device for generating forces on the macroions including means for applying a centrifugal force, means for applying a magnetophoretic force, and means for applying a constant or variable electrophoretic force. In a separation step the centrifugal and magetophoretic forces assist in forming the macroions in separate groups of concentric bands on a rotating platform. The constant electrophoretic force may be optionally used to assist in this step. In an analytical step to characterize the mass and charge of the macroions, the electrophoretic and magnetophoretic forces are used to oppose the centrifugal force to control and hold the macroion bands at fixed positions on the platform. A band detection means is used to characterize the positions of the macroion bands on the platform. The variable electrophoretic force may be optionally used in a detection part of the analytical step. Various embodiments of the band detection means are illustrated.

Claims20

Dependent claims

A method for characterizing the mass and charge of a plurality of macroions in a mixture of macroions, said method comprising:

generating a controllable centrifugal force on said macroions by rotating a quantity of said mixture substantially in a plane such that different radial velocities are produced on the plurality of macroions depending upon their mass;
applying a magnetic field of a controllable magnitude and direction such that a Lorenz force is generated to assist or oppose said centrifugal force in the radial direction, said Lorenz force acting on said macroions according to their charge and tangential velocity;
separating said macroions along the plane because of their different radial velocities such that a profile of velocities are developed along the radial direction of said plane;
reversing and controlling said magnetic field so that the Lorenz force acts substantially equally and oppositely to said centrifugal force and produces a stopage of the motion of said macroions in said radial direction;
applying an electric field of a controllable magnitude and direction such that an electrophoretic force is generated assisting said centrifugal force in the radial direction prior to reversing said magnetic field;
measuring the distribution of radial positions at which macroions group together;
and
determining the mass and charge of the macroions of said mixture from the values of the magnetic field, the electric field, the centrifugal field, and the radial positions.

5 more elements

An apparatus for separating a mixture of macroions contained in a fluid of a certain dielectric constant and ionic strength, said apparatus comprising:

means for rotating a quantity of said macroion fluid substantially in a plane so that a separation of the macroions occurs because of a centrifugal force acting in the radial direction of said plane, said separation causing groupings of said macroions in bands having radial velocities which are related to the macroion mass;
means for controlling the angular velocity of said rotation means;
means for generating a magnetic field perpendicular to said plane causing a Lorenz force to act in a radial direction to separate said macroions according to their charge and angular velocity;
means for controlling the direction and intensity of said magnetic field;
means for generating an electric field in said rotational plane and directed radially causing an electrophoretic force to be applied to said macroions according to their charge;
means for controlling the direction and intensity of said electric field;
means for detecting the radial position of a group of macroions on said rotational plane separated by their mass and charge;
and
means, responsive to said detecting means, for regulating said angular velocity controlling means, said electric field controlling means, and said magnetic field controlling means based upon the position of at least one of said macroion bands such that the radial velocity of said band may be controlled.

6 more elements

Dependencies are inferred from the claim text.

Apparatus and method for the analysis and separation of macroions

Life of this patent

Apparatus and method for the analysis and separation of macroions

Life of this patent

Abstract

Claims20