A method of providing a droplet in contact with a magnetically responsive bead and having a reduced quantity of a substance. The method generally includes the steps of (a) providing a droplet actuator (200) comprising: (i) a substrate (210) comprising electrodes (214) arranged for conducting droplet operations on a surface; (ii) a starting droplet (218/222) comprising: (1) one or more magnetically responsive beads (220); (2) a starting quantity of the substance; and (3) a starting volume; (b) magnetically immobilizing the one or more magnetically responsive beads at a location which is at a distance from a target droplet splitting zone, (224); (c) conducting one or more droplet operations comprising droplet dividing operations selected to divide the combined droplet to yield a set of droplets comprising: (i) a droplet (218) comprising substantially all of the one or more magnetically responsive beads and having a decreased quantity of the substance relative to the starting concentration; and (ii) a droplet (222) substantially lacking the magnetically responsive beads.

Droplet actuator devices and methods employing magnetic beads

A polymer comprising phospholipid moieties and a biocompatible polymer backbone, a composition comprising the polymer and optionally a bioactive agent, an implantable devices such as a DES comprising thereon a coating comprising the polymer and optionally a bioactive agent, and a method of using the device for the treatment of a disorder in a human being are provided.

Phosphoryl choline coating compositions

A method for the production of an esterified product is provided which affords an esterified product with high quality by repressing, during the esterification reaction of an alcohol with (meth)acrylic acid, the occurrence of impurities, particularly gel, to be formed owing to the polymerization of the alcohol and the (meth)acrylic acid as raw materials, the esterified product consequently formed, or the mixture thereof. Specifically, a method for the production of an esterified product of this invention comprises esterifying an alcohol represented by the following formula (1): R 1 O(R 2 O) n H  ( 1 ) wherein R 1 represents a hydrocarbon group of 1 to 30 carbon atoms, R 2 O represents an oxyalkylene group of 2 to 18 carbon atoms, providing that the repeating units, R 2 O, may be the same or different and that when the R 2 O's are in the form of a mixture of two or more species, the repeating units, R 2 O, may be added either in a block form or in a random form, and n represents an average addition mol number of oxyalkylene groups and is in the range of 0 to 300, with (meth)acrylic acid in a dehydrating solvent in the presence of an acid catalyst and a polymerization inhibitor, wherein a reaction temperature during the esterification reaction is not higher than 130° C. and a circulation speed of the solvent during the esterification reaction is not less than 0.5 cycle/hour.

Method for production of esterified product

The present invention provides an agglutination immunoassay, wherein the agglutination of insoluble carrier particles such as latex are stabilized and uniformized to give good reproducibility, and a reagent therefor. In the agglutination immunoassay which comprises allowing an antigenic substance in a sample to bind to insoluble carrier particles carrying substantially neither antigens nor antibodies thereon, and allowing an antibody or an antibody complex which reacts specifically to the antigenic substance to bind to the antigenic substance to give a selective agglutination of the insoluble carrier particles, a homopolymer prepared by polymerization of a monomer such as 2-methacryloyloxyethyl phosphorylcholine having a phosphorylcholine group and a vinyl group, or a copolymer prepared by polymerization of a monomer having a phosphorylcholine group and a vinyl group, with a monomer having a vinyl group such as n-butyl methacrylate is used.

Highly reproducible agglutination immunoassay method and reagents

An affinity particle, characterized in that it comprises an inorganic particle, a phosphoryl coline group represented by the following formula (1) bound to the surface of the particle by a covalent bonding, and a ligand having the specific affinity to an objective material bound to the particle by a covalent bonding or adsorption. An affinity separation method using the above affinity particle utilizes inorganic particles being produced at a low cost and allows the separation of an objective material with simplicity and ease and with high accuracy.

Affinity particle and affinity separation method

PURPOSE:To suppress the adsorption of protein to antibody combination solid phase, antigen combination solid phase, or solid phase and then improve analysis accuracy without affecting a measurement system by a specific protein adsorption inhibitor. CONSTITUTION:A protein adsorption inhibitor containing 2- methacryloyloxyethylphosphorylcholine(MPC) polymer and/or copolymer of MPC-containing constituent is used. The applicable range is the analysis method of living thing related substance where enzyme reaction or immunity or the antigen antibody reaction of immunity globulin are generally utilized. The MPC polymer and/or MPC copolymer using the protein adsorption inhibitor are the MPC individual polymer or a copolymer with other vinyl monomers and the NIPC content within the constituent of the polymer A is preferable 1-100mol.% and an average molar weight is preferable 1000-1,000,000. The inhibitor can be used by adding itself to a solvent medium where the polymer A can be dissolved, for example, phosphoric acid buffer solution, acetic buffer solution, and carbon buffer solution.

Protein adsorption inhibitor

PROBLEM TO BE SOLVED: To obtain a copolymer containing a phosphorylcholilne group- containing monomer and a silyl group-containing monomer as constituents, capable of being adhered to the surfaces of substrates such as a glass substrate by simple operations, having high durability and high biological adaptability, and useful as a material for medical treatments, etc. SOLUTION: This copolymer is obtained by randomly or alternately copolymerilzing a phosphorylcholine group-containing monomer of formula I [X is a divalent residual group; Y is a 1-16C alkyleneoxy; Z is H, R -0-CO (R is a 1-10C alkyl, etc.); (m) is 0-10; R is H, methyl; R -R are each H, a 1-6C hydroxyhydrocarbon] with a silyl group-containing monomer of formula II [w is -(CH2 )k (k is 0-4), etc.; R is H, methyl; R is a 1-10C alkoxy, a 6-14C aryloxy; R , R are each a 1-10C alkyl which may contain a halogen group], and has repeating units of formula III, uniformly distributed monomer constituent units (a, b), a number-average mol.wt. of 5,000-300,0000, and a (a):(b) ratio of 95:5 to 50:50.

Copolymer having phospholipid-like structure and medical material

PROBLEM TO BE SOLVED: To prevent a non-specific aggregation and a non-specific reaction at the measuring time by improving a developing solvent used for an immuno- chromatography method, and to thereby measure highly accurately. SOLUTION: This developing solvent for the immuno-chromatography is characterized by including a polymer having a phosphorylcholine group in a buffer solution. The polymer is preferably included with a concentration of 0.005-0.3 w/v%, and its number-average molecular weight is preferably over 40,000. The polymer preferably includes 2-methacryloyloxyethyl phosphorylcholine as a constitutive monomer, and may be a single polymer or a copolymer. COPYRIGHT: (C)2004,JPO

Developing solvent for immuno-chromatography, measuring method and kit

PROBLEM TO BE SOLVED: To obtain the subject solid phase useful for clinical diagnosis, capable of suppressing nonspecific adsorption and carrying out measurement excellent in sensitivity and reproducibility, by adsorbing a phosphorylcholine group- containing polymer on a stationary phase prepared by immobilizing an immunologically active substance to a carrier. SOLUTION: A phosphorylcholine group-containing polymer of the formula (R is a 1-10C hydrocarbon group) composed of a polymer obtained by polymerizing a polymerizable component containing 2-methacryloyloxyethyl-2'-(trimethyl ammonio)ethyl phosphate is adsorbed on an immunologically active substance immobilized stationary phase prepared by immobilizing an immunologically active substance (e.g. antibody) to a carrier (e.g. titer plate made of polystyrene) to give the objective polymer absorbing immunologically active substance immobilized stationary phase capable of carrying out measurement excellent in sensitivity and reproducibility while preventing nonspecific adsorption to an immunologically active substance-immobilized stationary phase useful in a two- site method (sandwich measurement) widely used in the field of clinical diagnostic.

Polymer adsorbed immunologically active substance immobilizing stationary phase

PROBLEM TO BE SOLVED: To provide a fine particle dispersant for clinical examination having high reproducibility and high sensitivity and treatable by a simple method suitable to an automatic analyzer in which the dispersion stability of a fine particle- containing reagent is improved, and the re-dispersibility is improved without deteriorating the activity of an antibody, antigen or the like bonded to the clinical examination fine particles coagulated in the process of reagent regulation or in the process of measurement. SOLUTION: This fine particle dispersant for clinical examination contains a polymer obtained by polymerizing a monomer composition containing a phosphoryl chorine-analogous group-containing monomer as effective component.

Sakaki Hidejiro

Papers

Protein adsorption inhibitor

Copolymer having phospholipid-like structure and medical material

Developing solvent for immuno-chromatography, measuring method and kit

Polymer adsorbed immunologically active substance immobilizing stationary phase

Fine particle dispersant for clinical examination, examination reagent, producing method of reagent, examination method and use