Patents by Inventor Yoshitsugu Sakata

Yoshitsugu Sakata 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 an analyte with an oxidase and an oxidizable color reagent and surfactants
    Patent number: 5384248
    Abstract: A substrate or an enzymatic activity in a body fluid can be measured accurately without influences of interfering substances such as bilirubin by reacting an oxidase corresponding to an analyte with the analyte or an oxidase corresponding to a substance produced by enzymatic reaction with the substance in a measuring system containing one or more cationic and/or amphoteric surfactants, followed by optical measurement of hydrogen peroxide produced by the reaction.
    Type: Grant
    Filed: April 15, 1994
    Date of Patent: January 24, 1995
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Toshiro Hanada, Ryosuke Matsuda, Yoshiyuki Matsuda
  • Stabilizing method for immuno active substances immobilized on insoluble carrier and its use in preparation of reagent for measuring physiologically active substances
    Patent number: 5273908
    Abstract: An immuno active substance immobilized on a carrier and stabilized by immersing the carrier in a solution of at least one of sugars and proteins can be used for measuring a physiologically active substance even after stored for a long period of time. A preferred embodiment of the invention uses a synergistic mixture of a sugar and a protein as the stabilizing agents.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: December 28, 1993
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Yoshitaka Hamaguchi, Motoo Goto, Shinzo Kobatake
  • 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
  • Acidic gas absorbent and process for production thereof
    Patent number: 5030610
    Abstract: A molded acidic gas absorbent produced by press molding powders, etc. of calcium hydroxide and one or more powders, etc. of alkali metal hydroxides and alkaline earth metal hydroxides except for calcium hydroxide, impregnating the molded article with water, followed by heat treatment while maintaining a predetermined amount of water therein is effective for absorbing an acidic gas such as CO.sub.2 in air and a narcotic gas.
    Type: Grant
    Filed: April 16, 1990
    Date of Patent: July 9, 1991
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Shinogu Fukahori, Hiroyuki Kodera, Kenzi Iwata
  • Reagents for determining peptidoglycan and .beta.-1,3-glucan
    Patent number: 4970152
    Abstract: A reagent comprising a fraction obtained from plasma of an insect such as silkworm larvae and capable of reacting specifically with .beta.-1,3-glucan or peptidoglycan can be used for determining .beta.-1,3-glucan or peptidoglycan.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: November 13, 1990
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Masaaki Ashida, Masakazu Tsuchiya, Yoshitsugu Sakata, Shuji Matsuura
  • 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
  • Process for measuring endotoxin and apparatus used therefor
    Patent number: 4740460
    Abstract: Endotoxin contents in samples can be determined qualitatively, or quantitatively, singly or in parallel, with high precision in a short time by a process comprising applying a light to each sample solution, measuring an initial transmitted light amount I.sub.0 and a transmitted light amount at a time t, I(t), to give a ratio R(t)=I(t)/I.sub.0, and judging a gelation point by a threshold value of R(t), or further obtaining a gelation time from the gelation point. An apparatus used therefor is also disclosed.
    Type: Grant
    Filed: June 26, 1985
    Date of Patent: April 26, 1988
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Haruki Oishi, Yasumichi Hatayama, Hiromi Shiraishi, Kazuya Yanagisawa
  • Process for quantitative determination of substrate treated with oxidase
    Patent number: 4695539
    Abstract: A substrate in a sample can be determined quantitatively by measuring colorimetrically superoxide ion generated by treating the sample with a specific oxidase corresponding to the substrate to be determined, said oxidase treatment and measuring of the generated superoxide ion being conducted by using a reagent composition comprising (a) an oxidase, (b) peroxidase, (c) a phenol and/or an amine, (d) a thiol compound, (e) a color producing reagent to be reduced, and if necessary (f) a chelating agent.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: September 22, 1987
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Yoshibonu Miyashita, Tadashi Hamanaka, Hiroyuki Kodera, Yutaka Miki, Kazuhiko Yamanishi, Toshiro Hanada
  • Composition, method and test strip for examining urobilinogen
    Patent number: 4665038
    Abstract: A composition comprising a 9-fluorenone-2-diazonium salt, an acid or acidic salt which is solid at normal temperatures, and if necessary an anionic surface active agent can produce a vivid red color instantly by reacting with urobilinogen without interfered with bilirubin.
    Type: Grant
    Filed: October 12, 1984
    Date of Patent: May 12, 1987
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Tadashi Hamanaka, Kenzi Iwata, Misato Nakaue
  • Water-soluble cross-linked polymer of lysyl endopeptidase, process for preparing same and use of same
    Patent number: 4634671
    Abstract: A water-soluble cross-linked polymer of the enzyme lysyl endopeptidase produced by Achromobacter lyticus and a process for preparing the polymer as well as a semi-synthesis of human insulin using the polymer.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: January 6, 1987
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Yoshitsugu Sakata, Akinori Shintani, Tetsuya Matsuo, Haruhiko Sugiyama, Nobuyuki Tokioka