Magnetic-polymer particles

• US 5,866,099 A
• Filed: 04/30/1997
• Issued: 02/02/1999
• Est. Priority Date: 10/04/1985
• Status: Expired due to Fees

• Current Assignee: Veridex LLC (Johnson & Johnson)
• Original Assignee: Nycomed A/S (Takeda Pharmaceutical Company Limited)
• Inventors: Silvia, John C., D'Angelo, Louis, Owen, Charles S., Liberti, Paul A.
• Primary Examiner(s): Hollinden, Gary E.
• Application Number:
  US08/846,575
• Time in Patent Office: 643 Days
• Field of Search: 424/9.322, 424/9.323, 424/646, 424/648, 436/173, 428/551, 514/6, 514/54, 514/57, 514/59, 600/420
• US Class Current: 424/9.322
• CPC Class Codes: A61K 49/1818 particles, e.g. uncoated or non-functionalised microparticles or nanoparticles
• CPC Class Codes: A61K 9/5094 Microcapsules containing magnetic carrier material, e.g. ferrite for drug targeting
• CPC Class Codes: C12N 11/14 Enzymes or microbial cells immobilised on or in an inorganic carrier
• CPC Class Codes: G01N 2333/765 Serum albumin, e.g. HSA
• CPC Class Codes: G01N 2446/20 the magnetic material being present in the particle core
• CPC Class Codes: G01N 2446/30 the magnetic material being dispersed in the polymer composition before their conversion into particulate form
• CPC Class Codes: G01N 33/54333 Modification of conditions of immunological binding reaction, e.g. use of more than one type of particle, use of chemical agents to improve binding, choice of incubation time or application of magnetic field during binding reaction
• CPC Class Codes: G01N 33/5434 using magnetic particle immunoreagent carriers which constitute new materials per se
• CPC Class Codes: Y10S 435/972 Modified antibody, e.g. hybrid, bifunctional
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A magnetic-polymer particle, useful in immunoassay techniques and various other biological/medical applications is produced by coprecipitation of transition metals in the presence of a polymer having available coordination sites. These particles are capable of forming stable aqueous suspensions and may be easily resuspended after agglomeration.

Claims

1. A method of separating a target substance from a non-target substance within a fluid mixture, comprising the steps of:

combining the fluid mixture with resuspendable, magnetic-polymer particles in a container, to produce a suspension comprising a magnetic component and a non-magnetic component, wherein the magnetic component comprises magnetic particles bound to the target substance through at least one substance on the surface of the magnetic particles which directly or indirectly binds to the target substance and the non-magnetic component comprises the remainder of the fluid mixture, including the non-target substance, and wherein the magnetic-polymer particles are produced by a process comprising the steps of;

(a) combining a first aqueous solution of at least two species of transition metal ions capable of reacting with each other to form a magnetic precipitate and a polymer having available coordination sites in proportions adapted to produce a resuspendable product;

(b) reacting said transition metal ions in the presence of said polymer to form a magnetic precipitate comprising magnetic-polymer particles; and

(c) recovering said magnetic-polymer particles;

generating in the container, a magnetic field;

attracting the magnetic particles toward a collection surface; and

collecting the magnetic component upon the collection surface, thereby separating the target substance from the non-target substance.