Method of urinalysis, urinalysis apparatus, method of measuring angle of rotation and polarimeter

• US 6,166,807 A
• Filed: 08/19/1997
• Issued: 12/26/2000
• Est. Priority Date: 11/16/1995
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Kawamura, Tatsurou, Onishi, Hiroshi, Sonoda, Nobuo
• Primary Examiner(s): Pham, Hoa Q.
• Application Number:
  US08/860,937
• Time in Patent Office: 1,225 Days
• Field of Search: 356/364, 356/365, 356/366, 356/367, 356/368, 250/225, 600/316, 600/322
• US Class Current: 356/364
• CPC Class Codes: G01J 4/00 Measuring polarisation of light
• CPC Class Codes: G01N 21/21 Polarisation-affecting properties G01N21/19 takes precedence
• CPC Class Codes: G01N 33/493 urine

Abstract

The present invention provides a urinalysis apparatus easy to maintain and manage without using any supplies such as the test paper, in which the concentration of an optically active substance in urine is determined by measuring the angle of rotation of the urine. Also, a polarimeter and a urinalysis apparatus which are reliable, compact and inexpensive are provided by using a polarimeter including means for transmitting the polarized light through a specimen, applying a magnetic field to the specimen and detecting the change in the direction of light polarization due to the application of the magnetic field.

Claims

1. A method of urinalysis in which a concentration of an optically active substance in urine is determined, the method comprising the steps of

measuring an angle of rotation of said urine, wherein the angle of rotation is measured in the urine containing a substance to be measured having an optical rotary power and an optically active substance of a known concentration;

and

determining the range of concentration C (kg/dl) of said substance to be measured using the following equation;

space="preserve" listing-type="equation">(A-A.sub.h)/(α

×

L)<

C<

(A-A.sub.1)/(α

×

L)

space="preserve" listing-type="equation">A.sub.h =L×

a×

C.sub.h

space="preserve" listing-type="equation">A.sub.1 =L×

a×

C.sub.1

where

A_h ;

angle of rotation (degree) of urine measured measured at a maximum value (kg/dl) of concentration of optically active substance of a known concentration,

A_l ;

angle of rotation (degree) of urine measured measured at a minimum value (kg/dl) of concentration of optically active substance of a known concentration,

C_h ;

maximum value (kg/dl) of concentration of optically active substance of a known concentration,

C₁ ;

minimum value (kg/dl) of concentration of optically active substance of a known concentration,

α

;

specific angle of rotation (degree/cm·

dl/kg) of a substance to be measured,

a;

specific angle (degree/cm·

dl/kg) of rotation of optically active substance of a known concentration,

and

L;

measurement light path length (cm).

2. The method of urinalysis in accordance with claim 1, wherein the urine containing N kinds of optically active substance s is subjected to the measurements of the angle of rotation using the light of at least N kinds of wavelengths, respectively, to determine the concentrations of optically active substances in said urine, N being more than one.

3. The method of urinalysis in accordance with claim 1, wherein the concentration of said optically active substance and the concentration of a light scattering substance in said urine are determined by measuring a quantity of light scattered by said urine in addition to the measurement of the angle of rotation of said urine.

4. The method of urinalysis in accordance with claim 1, wherein said optically active substance is at least one selected from the group consisting of protein, sugar and L-ascorbic acid.

5. The method of urinalysis in accordance with claim 1, wherein said angle of rotation of the urine is measured with respect to the light having a wavelength of 500 nm or more.