Patents by Inventor Masaaki Kida

Masaaki Kida has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for measuring complement activity and reagent used therefor
    Patent number: 6015679
    Abstract: A reagent composition comprising (a) liposomes encapsulating a marker therein, immobilizing a hapten on liposome membranes and having a size in the range of 100 to 500 nm in terms of mean particle size plus twice the standard derivation, and (b) an antibody to the hapten is effective for measuring human complement activity easily and precisely with excellent storage stability.
    Type: Grant
    Filed: May 20, 1998
    Date of Patent: January 18, 2000
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Kazuhisa Kubotsu, Sachiko Yamamoto, Masaaki Kida
  • Process for measuring complement activity and reagent used therefor
    Patent number: 5854082
    Abstract: A reagent composition comprising (a) liposomes encapsulating a marker therein, immobilizing a hapten on liposome membranes and having a size in the range of 100 to 500 nm in terms of mean particle size plus twice the standard derivation, and (b) an antibody to the hapten is effective for measuring human complement activity easily and precisely with excellent storage stability.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: December 29, 1998
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Kazuhisa Kubotsu, Sachiko Yamamoto, Masaaki Kida
  • Immunoassay using liposomes
    Patent number: 5654156
    Abstract: Complement immunoassay using liposomes is improved by pretreatment of a sample solution before determination of analyte comprising acidifying or alkalinizing the sample solution, followed by changing the pH to about neutral so as to remove influences caused by interfering substances present in the sample.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: August 5, 1997
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Kazuhisa Kubotsu, Masaaki Kida, Sachiko Goto
  • Process for quantitatively lysing liposomes and a process for determining the amount of an analyte using same
    Patent number: 5501953
    Abstract: Membranes of liposomes fixing biotin on membrane surfaces thereof can be lysed by a mixed agent comprising a surfactant and avidin. This mechanism can be applied to immunoassay for determining an analyte, e.g. antigen or antibody, wherein liposomes encapsulating a marker and fixing biotin on membrane surfaces thereof are lysed depending on hindrance of an avidin-biotin binding reaction by a specific reaction caused by the analyte.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: March 26, 1996
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Minoru Fujita, Masaaki Kida
  • Immunoassay process and liquid reagents used therefor
    Patent number: 5221613
    Abstract: A combination of reagents including (i) a first liquid containing (a) first microcapsules having an analyte immobilized on surfaces thereof and containing a marker therein and (b) microcapsules encapsulating an antibody and having different capsule walls from said first analyte immobilized microcapsules with respect to susceptibility to a capsule wall lysin, and (ii) a second liquid containing complement is suitable for immunoassay based on complement-dependent immune lysis of microcapsules.
    Type: Grant
    Filed: February 1, 1990
    Date of Patent: June 22, 1993
    Assignee: Wako Pure Chemical Industries Ltd.
    Inventors: Masaaki Kida, Kazunisa Kubotsu, Shuji Matuura
  • Urea derivatives
    Patent number: 5041636
    Abstract: Urea derivatives of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently a 4-disubstituted aminoaryl group or the like, and R.sup.3 is a carboxyalkyl group or the like, is soluble in water and effective as a color producing reagent for determining hydrogen peroxide or the like or the activity of peroxidase.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: August 20, 1991
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Kazunari Hashidume, Tsutomu Iwata, Toyoharu Mukai, Masaaki Kida
  • Urea derivatives
    Patent number: 4879383
    Abstract: Urea derivatives of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently a 4-disubstituted aminoaryl group or the like, and R.sup.3 is a carboxyalkyl group or the like, is soluble in water and effective as a color producing reagent for determining hydrogen peroxide or the like or the activity of peroxidase.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: November 7, 1989
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Kazunari Hashidume, Tsutomu Iwata, Toyoharu Mukai, Masaaki Kida
  • Novel functionallized liposomes and a process for production thereof
    Patent number: 4861597
    Abstract: Novel functionallized liposomes containing a high-molecular-weight amphiphilic compound such as LPS etc. as one of matrix material have a very high encapsulation efficiency and readily undergo lysis. Moreover, antigen, antibody, etc. can be immobilized on the liposomes efficiently with a sufficient binding rate by using the amphiphilic compound as a spacer.
    Type: Grant
    Filed: May 19, 1987
    Date of Patent: August 29, 1989
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Masaaki Kida, Isako Kitabata, Kazuhisa Kubotsu, Yoshitsugu Sakata