Automatic analyzer

Patent metadata

Field	Value
Publication number	US-9488667-B2
Application number	US-201013318819-A
Country	US
Kind code	B2
Filing date	Apr 12, 2010
Priority date	May 11, 2009
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

To change a photometric time for each item or to change a measurement time for each specimen so that time required for biochemical measurement can be reduced, an index that indicates an end of a reaction is required. Unfortunately, however, no methods have been available for determining the end of the reaction. In measuring a substance to be measured contained in a sample, a parameter in an approximate expression is calculated using a measured value that changes with time, a degree of convergence of a reaction is determined according to a degree of convergence of the parameter, and a measured value at the end of the reaction is calculated using the parameter at a point in time at which it is determined that the reaction has converged.

First claim

The invention claimed is:

1. An automatic analyzer comprising:
a storage device that stores a plurality of approximate expressions each representing changes over time of a plurality of reaction processes of a plurality of specimens and reagents, each of the approximate expressions being associated with a corresponding test item or one of the specimens;
a photometer which measures actual values of one of the reaction processes of one of the specimens and reagents in a reaction vessel at predetermined intervals; and
a computer connected to the storage mechanism and the photometer, and which is programmed to execute:
a parameter optimizing mechanism which optimizes one or more parameters of one of the approximate expressions associated with the one of the specimens in the reaction vessel to the actual values of the one of the reaction processes measured by the photometer whenever the actual values of the one of the reaction processes are measured at the predetermined intervals; and
a determining mechanism which converts changes in the one or more parameters, which are optimized by the parameter optimizing mechanism whenever the actual values of the one of the reaction processes are measured at the predetermined intervals, into a numeric value, and determines whether or not the numeric value falls within a predetermined range over time,
wherein a measured value of the one of the reaction processes is calculated from the optimized parameters of the one of the approximate expressions associated with the one of the reaction processes measured by the photometer when the determining mechanism determines the numeric value falls within the predetermined range.

2. The automatic analyzer according to claim 1 , wherein the computer is further programmed to execute:
a measured value calculating mechanism to establish the one of the approximate expressions based on the parameters optimized by the parameter optimizing mechanism and calculating the measured value at an end of the one of the reaction processes using the established approximate expression, when the determining mechanism determines that the numeric value falls within the predetermined range the predetermined range, and
wherein the storage device further stores a plurality of calibration curves which are each associated with a corresponding test item or one of the specimens, and
wherein the measured value is converted to a concentration of a substance to be measured in the one of the specimens in the reaction vessel with one of the calibration curves associated therewith stored in the storage device.

3. The automatic analyzer according to claim 1 , wherein:
the determining mechanism stores the predetermined range as a reference space, calculates a Mahalanobis distance based on a change in the parameters at a current point in time, and thereby determines that the predetermined range is reached.

4. The automatic analyzer according to claim 1 , wherein:
the determining mechanism determines whether the numeric value falls within the predetermined range using a neural network.

5. The automatic analyzer according to claim 1 , wherein the computer is further programmed to execute:
an approximate expression selecting mechanism to select the one of the approximate expressions from among the approximate expressions according to the substance to be measured or the reagents for the corresponding test item or specimen.

6. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a 0 +a 1 *exp(− k 1 *t )+ a 2 *exp(− k 2 *t ),

where t denotes a measurement point in time, x denotes a calculated value, and * denotes a symbol representing multiplication; and
the parameters include a 0 , a 1 , a 2 , k 1 , and k 2 .

7. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a 0 +Σ{a i *exp(− k i *t )},

where t denotes a measurement point in time, x denotes a calculated value, Σ{ } denotes a symbol representing a sum of all values, each value being obtained by substituting i in { } for a value of 1 to n, n denotes a natural number, and * denotes a symbol representing multiplication; and
the parameters include a 0 , a i , and k i .

8. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=c +(1/( b 0 +b 1 *t )),

where t denotes a measurement point in time, x denotes a calculated value, and * denotes a symbol representing multiplication; and
the parameters include b 0 , b 1 , and c.

9. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=d +( e /(exp( r*t )+ s )),

where t denotes a measurement point in time, x denotes a calculated value, and * denotes a symbol representing multiplication; and
the parameters include d, e, r, and s.

10. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+h ( t ,ψ),

where t denotes a measurement point in time, x denotes a calculated value, ψ denotes a plurality of parameters, and * denotes a symbol representing multiplication; and
the parameters include a, b, and ψ and a concentration of a substance to be measured is calculated from a value of a.

11. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+c 1 *exp(− k 1 *t ),

where t denotes a measurement point in time, x denotes a calculated value, and * denotes a symbol representing multiplication; and
the parameters include a, b, c 1 , and k 1 .

12. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+Σ{c i *exp(− k i *t )},

where t denotes a measurement point in time, x denotes a calculated value, Σ{ } denotes a symbol representing a sum of all values, each value being obtained by substituting i in { } for a value of 1 to n, n denotes a natural number, and * denotes a symbol representing multiplication; and
the parameters include a, b, c i , and k i .

13. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+e /( t+d ),

where t denotes a measurement point in time, x denotes a measured value, and * denotes a symbol representing multiplication; and
the parameters include a, b, d, and e.

14. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+w /{exp( u*t )+ v},

where t denotes a measurement point in time, x denotes a measured value, and * denotes a symbol representing multiplication; and
the parameters include a, b, u, v, and w.

15. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=a*t+b+p *log{1+ q *exp( r*t )},

where t denotes a measurement point in time, x denotes a calculated value, and * denotes a symbol representing multiplication; and
the parameters include a, b, p, q, and r.

16. The automatic analyzer according to claim 1 , wherein:
at least one of the approximate expressions is:
x=g ( t ,φ),

where t denotes a measurement point in time, x denotes a calculated value, and φ denotes a plurality of parameters;
the parameter are represented by φ; and
a concentration of a substance to be measured is calculated from a value of a first-order derivative g′(t, φ) with respect to time of the expression at t at which an absolute value of a second-order derivati

Assignees

• Kamihara Kumiko
• Mitsuyama Satoshi
• Mimura Tomonori
• Manri Chihiro
• Hitachi High Tech Corp

Inventors

• Kamihara Kumiko
• Mitsuyama Satoshi
• Mimura Tomonori
• Manri Chihiro

Classifications

• G01N35/00613 Primary

  Quality control · CPC title

• G01N2035/0097

  monitoring reactions as a function of time · CPC title