Polymer Laboratories Limited

Solid Phase Sciences Corporation

Stiftung Fur Diagnostische Furschung

Graham Margetts

Irving Sucholeiki

Peter Schwind

Michael J Marshall

Roderick N Hobbs

David Bashforth

Mark J J Roberts

Mark Roberts

The present invention relates to a material containing ionic groups that form an ionic pair with a free radical catalyst. In particular, the invention relates to materials that are magnetic, and to the methods of forming such materials. For example, a method of forming paramagnetic particles is disclosed, the method comprising contacting a substance having cationic groups with an aqueous solution of Feso that all the cationic groups are exchanged for Fe, adjusting the pH of the solution to betweenand, to form Fe(III) hydroxide, reducing a portion of the Fe(III) hydroxide to Fe(II) hydroxide to obtain a blend of the Fe(III) hydroxide the Fe(II) hydroxide, and crystallizing the two iron hydroxides to form paramagnetic particles comprising magnetite. The invention also discloses the formation of polymers from the ionic groups within the material. Various applications of the resulting materials are also disclosed.

Ionic material

The present invention relates to a material containing ionic groups, in particular, to the ionic materials that form an ionic pair with a free radical catalyst. Various applications of such materials are also described. Ionic materials can include magnetic particles. Examples of free radical catalysts that can be used include 2,2'-azobis(2 -methylpropionamidine) dihydrochloride, and 2,2&#x2032;-azobis[2-(2-imidazolin-2-yl) propane]dihydrochloride.

Described is a method and reagent kit for the detection of an analyte in a sample liquid by agglutination, wherein the sample liquid is contacted with an agglutination reagent in a reaction vessel that contains an inert matrix to form a reaction mixture that is then subjected to centrifugation. The reaction between the analyte and the agglutination reagent is determined based upon the penetration of the agglutination reagent into the inert matrix. The agglutination reagent includes synthetic particles having an average diameter and specific density chosen such that the particles' sedimentation behavior towards the matrix is essentially the same as that of erythrocytes under the same centrifugal conditions. Preferably, the surfaces of the synthetic particles have ligand molecules immobilized thereon for binding to the analyte.

Synthetic particles as agglutination reagents

This invention provides a novel composite magnetic bead and a method for making the composite magnetic bead. The composite magnetic bead is comprised of a matrix formed from vinyl monomers throughout which is distributed primary beads, each primary bead of which is a magnetizable metal oxide encapsulated in a rigid polymeric coating. The matrix structure allows the composite magnetic bead to swell in organic solvents without loss of the intermeshed primary beads. Further, the matrix can be functionalized to allow the covalent bonding of sites useful for organic syntheses. The composite magnetic beads are made utilizing a core-shell polymerization techinque under conditions which preserve the oxidation state of the magnetizable metal oxide in the primary particles. In one embodiment, primary beads, each having a hydrophobic exterior surface, are dispersed in an inert solvent with a vinyl monomer and a crosslinking agent for that monomer to form a dispersed phase. The dispersed phase is mixed into an aqueous solvent-dispersing agent phase and stirred until the desired droplet size is achieved, then polymerization is initiated. After removal of the solvent and unreacted components, the composite magnetic beads are dried and sieved.

Growing community of inventors

Shrewsbury, United Kingdom

Graham Margetts