Glucose level measuring apparatus

• US 4,717,546 A
• Filed: 11/19/1984
• Issued: 01/05/1988
• Est. Priority Date: 11/19/1984
• Status: Expired due to Fees

• Current Assignee: Texas Tech University Health Sciences Center (Texas Tech University System)
• Original Assignee: Texas Tech University Health Sciences Center (Texas Tech University System)
• Inventors: Barnett, J. Craig
• Primary Examiner(s): Marcus, Michael S.
• Assistant Examiner(s): Delahunty, C. M.
• Application Number:
  US06/673,153
• Time in Patent Office: 1,142 Days
• Field of Search: 422/58, 422/63-66, 422/68, 436/66, 436/95, 436/169
• US Class Current: 422/63
• CPC Class Codes: G01N 2035/00039 Transport arrangements specific to flat sample substrates, e.g. pusher blade
• CPC Class Codes: G01N 2035/00108 Test strips, e.g. paper
• CPC Class Codes: G01N 2035/00752 bar codes
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001
• CPC Class Codes: G01N 35/00029 provided with flat sample substrates, e.g. slides G01N35/028 takes precedence

Abstract

An apparatus for automatically performing a blood glucose test includes a cylindrical carrier with a holder for receiving a reagent pad. Upon receiving the pad, the carrier holds the pad for a predetermined reaction time and then rotates the pad successively to washing and de-watering stations. After de-watering, the pad is presented to a measuring station at which a reflectometer evaluates the color characteristics of the pad. A display of glucose level as a function of the color change of the pad is presented.

Claims

1. An apparatus for performing a test to determine the glucose level in a sample of blood placed on a reagent pad attached to an elongated test strip of flexible material, the apparatus comprising the combination of individual means respectively defining a receiving station, a wash station, a de-watering station, and a measuring station in spaced relationship from each other;

carrier means for holding a test strip having a reagent pad thereon, said carrier means being movable to transport a test strip having a reagent pad thereon to each of said stations in sequence, said carrier means comprising

a generally cylindrical body having a central axis, said stations being disposed around the circumference of said body;

means for mounting said body for rotation about said central axis;

an axially extending holder on said body for receiving and retaining said pad, said holder including means for receiving and retaining a test strip having a reagent pad thereon comprising an elongated body having a flat portion dimensioned to receive (said) a test strip having a reagent pad thereon, said elongated body being slidably mounted on said cylindrical body for axial movement between a retracted position and an extended position; and

means for controllably moving said elongated body between said retracted and extended positions, said means defining a receiving station located at the same axial position with respect to said central axis as the extended position of said elongated body and said individual means defining a wash station, a de-watering station and a measuring station being located at the same axial position with respect to said central axis as the retracted position of said elongated body, control and drive means for moving said carrier means to transport a reagent pad mounted on a test strip elongated body to said stations and to hold (said) such a test strip sequentially at each of said individual means defining a watering station, a de-watering station and a measuring station while in said retracted position and at said means defining a receiving station while in said extended position for preselected intervals of time,

said means defining a wash station including means for washing a reagent pad mounted on a test strip retained by said elongated body when said carrier is moved to present said elongated body to said (said) means defining a wash station,

said means defining a de-watering station including means for removing superficial water remaining after washing from a reagent pad mounted on a test strip retained by said elongated body when said (pad) elongated body is moved to said means defining a de-watering station,

said means defining a measuring station including means for producing a signal representative of color characteristics of a reagent pad mounted on a test strip retained by said elongated body when said elongated body is moved to said means defining a measuring station, and

means for receiving said signal and for producing a display representative of color characteristics of a reagent pad mounted on a test strip which is carried by said elongated body.

2. An apparatus according to claim 1 wherein said means defining receiving, washing, de-watering and measuring stations are circularly spaced around said cylindrical body;

and wherein said control and drive means includes means for rotating said carrier in increments so that a test strip having a reagent pad thereon which is retained by said elongated body is moved sequentially between each of said stations.

3. An apparatus according to claim 1 wherein said means for washing includes a cup-shaped body having an open side facing toward said carrier means and being movable against said carrier;

a water supply;

a supply of air under pressure;

a discharge chamber in fluid communication with said cup-shaped body and said water supply;

means for delivering a measured quantity of water from said water supply to said discharge chamber;

valve means for introducing air under pressure from said supply of air under pressure into said discharge chamber to force water from said discharge chamber into said cup and against a reagent pad mounted on a test strip carried by said elongated body to wash a reagent pad which is so carried by said elongated body; and

drain means for draining water from said cup-shaped body.

4. An apparatus according to claim 1 wherein said means for removing superficial water includes

a strip of water-absorbent blotting paper;

and

means for pressing said blotting paper against a pad mounted on a test strip which is retained on said elongated body.

5. An apparatus according to claim 1 wherein said holder comprises

wall means on said cylindrical body extending radially outwardly relative to said central axis, the upper edges of said wall means having teeth thereon;

and said apparatus further comprises

gear means mounted above said holder at said receiving station for engaging said teeth; and

said means for controllably moving said elongated body comprises means for driving said gear means to move said elongated body of said holder between said extended and retracted positions.

6. An apparatus according to claim 5 wherein said means defining receiving, washing, de-watering and measuring stations are circularly spaced around said cylindrical body;

and wherein said control and drive means includes means for rotating said carrier in increments so that a test strip having a reagent pad thereon which is retained by said elongated body is moved sequentially between each of said stations.

7. An apparatus according to claim 6 wherein said means for washing includes a cup-shaped body having an open side facing toward said carrier means and means for moving said cup-shaped body against said carrier to enclose a reagent pad mounted on a test strip which is carried by said elongated body when said elongated body is located at said means defining a wash station;

a water supply;

a supply of air under pressure;

a discharge chamber in fluid communication with said cup-shaped body and said water supply;

means for delivering a measured quantity of water from said water supply to said discharge chamber;

valve means for introducing air under pressure from said supply of air under pressure into said discharge chamber to force water from said discharge chamber into said cup and against a reagent pad mounted on a test strip carried by said elongated body to wash a reagent pad which is so carried by said elongated body; and

drain means for draining water from said cup-shaped body.

8. An apparatus according to claim 7 wherein said means for removing superficial water includes

a strip of water-absorbent blotting paper, and

means for pressing said blotting paper against a pad mounted on a test strip which is retained on said elongated body.

9. An apparatus according to claim 5 wherein said means for washing includes a cup-shaped body having an open side facing toward said carrier means and means for moving said cup-shaped body against said carrier to enclose a reagent pad mounted on a test strip which is carried by said elongated body when said elongated body is located at said means defining a wash station;

a water supply;

a supply of air under pressure;

a discharge chamber in fluid communication with said cup-shaped body and said water supply;

means for delivering a measured quantity of water from said water supply to said discharge chamber;

valve means for introducing air under pressure from said supply of air under pressure into said discharge chamber to force water from said discharge chamber into said cup and against a reagent pad mounted on a test strip carried by said elongated body to wash a reagent pad which is so carried by said elongated body; and

drain means for draining water from said cup-shaped body.

10. An apparatus according to claim 5 wherein said means for removing superficial water includes

a strip of water-absorbent blotting paper;

and

means for pressing said blotting paper against a pad mounted on a test strip which is retained on said elongated body.

11. An apparatus according to claim 6 wherein said means for removing superficial water includes

a strip of water-absorbent blotting paper;

and

means for pressing said blotting paper against a pad mounted on a test strip which is retained on said elongated body.