EP0394041A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Capillary flow device and reading instrument
Assignee: Biotrack Inc
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Filing: 1990-04-19
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Granted: —
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Expires: 2010-04-19
Abstract
Abstract An instrument for performing assays is taught including one or more of the following features: an APTT test is performed utilizing a bandpass filter centered at approximately 45Hz in order to provide the best analysis of scattered light for properly detecting the endpoint of the APTT assay; a floating theshold voltage is used for comparison with the output signal, thereby avoiding problems which cause false endpoint detection; periodic determinations are made to ensure that an adequate supply of sample is present in the sample well, thereby avoiding false indications of an adequate supply of sample due to sample drying; pulses of light are used rather than modulated light, thereby obviating the need for a modulator while providing scattered light from a sample which can be easily distinguished from ambient light; unique codes contained on a quality check device are utilized for customization, for example, to establish the language in which the prompts will be presented to the user, or the units of measurement which will be displayed; and a thermal code is used to control the temperature of the cartridge containing the sample and one or more reagents within very close tolerances.
Inventors
- 👤 Paul James Lingane
- 👤 Brian Robert Carey
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 19:08
CPC Classifications
G; G01; G01N; G01N35/00; G01N35/00584; G01N35/00722; G01N35/00732; G01N11/00; G01N11/02; G01N11/04; G01N33/00; G01N33/48; G01N33/50; G01N33/86; G05; G05D; G05D23/00; G05D23/19; G01N2035/00742; G01N2035/00752; G01N2035/00762; G01N21/00; G01N21/75; G01N21/77; G01N21/82; G01N2201/00; G01N2201/12; G01N2201/122; G01N2201/1222
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
222 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent; determining a signal as a measure of said activity or the presence of concentration of said analyte in said sample; passing said signal through a filter to provide an output signal; detecting said output signal to provide a detected signal; and comparing said detected signal with a threshold voltage to determine when said flow has stopped, said threshold voltage being adjusted to track said detected signal relatively slowly such that a rapid change in said detected signal will fall below said threshold voltage.
Claim 2
Independent Claim
222 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent; determining a signal as a measure of said activity or the presence of concentration of said analyte in said sample; passing said signal through a filter to provide an output signal; detecting said output signal to provide a detected signal; and comparing said detected signal with a threshold voltage to determine when said flow has stopped, said threshold voltage being adjusted to track said detected signal relatively slowly such that a rapid change in said detected signal will fall below said threshold voltage.
Claim 3
Dependent Claim
13 words
A method according to Claim 1, wherein said filter is a bandpass filter.
Claim 4
Dependent Claim
18 words
A method according to Claim 2, wherein said bandpass filter has a center frequency of approximately 45 Hz.
Claim 5
Dependent Claim
19 words
A method according to Claim 3, wherein said bandpass filter has a 3 dB bandwidth of approximately 35 Hz.
Claim 6
Independent Claim
17 words
A method according to any one of the preceding claims wherein said analyte is an APTT assay.
Claim 7
Independent Claim
34 words
A method according to any one of the preceding claims wherein said detected signal must fall below said threshold voltage for a specified period of time to provide an indication that flow has stopped.
Claim 8
Dependent Claim
16 words
A method according to Claim 6, wherein said specific period of time is approximately 10 seconds.
Claim 9
Independent Claim
210 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; and determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample, wherein said detectable signal is a change in flow rate due to a stoppage of flow, and a periodic determination is made to insure that said stoppage of flow is not due to an inadequate supply of said fluid sample.
Claim 10
Independent Claim
210 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; and determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample, wherein said detectable signal is a change in flow rate due to a stoppage of flow, and a periodic determination is made to insure that said stoppage of flow is not due to an inadequate supply of said fluid sample.
Claim 11
Dependent Claim
46 words
A method according to Claim 8 wherein said each of said periodic determinations comprises the steps of: providing pulsed light to said fluid sample resulting in a detectable signal; and determining a signal at a specified frequency as an indication of the state of said sample.
Claim 12
Dependent Claim
21 words
A method according to Claim 9, wherein said specified frequency is selected to reduce undesired signal components due to ambient light.
Claim 13
Dependent Claim
17 words
A method according to Claim 9 or Claim 10, wherein said specific frequency is approximately 8 KHz.
Claim 14
Independent Claim
20 words
A method according to any one of Claims 9-11, wherein said detectable signal changes as said fluid sample is consumed.
Claim 15
Independent Claim
20 words
A method according to any one of Claims 9-12, wherein said periodic determination is made at approximately 2 second intervals.
Claim 16
Independent Claim
23 words
A method according to any one of Claims 9-13, wherein said periodic determination is made by observing light scatter at said inlet port.
Claim 17
Independent Claim
242 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, a reagent contained within the device, and a heater plate, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; and determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample, wherein the temperature of said sample in said device is maintained at a substantially constant temperature by the method of repeating the following sequence steps; measuring the ambient temperature; measuring the temperature of said heater plate temperature; updating a weighted average temperature; updating a calculated cartridge temperature; and adjusting the temperature of said heater plate to cause the calculated cartridge temperature to move closer to a desired cartridge temperature.
Claim 18
Independent Claim
242 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, a reagent contained within the device, and a heater plate, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; and determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample, wherein the temperature of said sample in said device is maintained at a substantially constant temperature by the method of repeating the following sequence steps; measuring the ambient temperature; measuring the temperature of said heater plate temperature; updating a weighted average temperature; updating a calculated cartridge temperature; and adjusting the temperature of said heater plate to cause the calculated cartridge temperature to move closer to a desired cartridge temperature.
Claim 19
Independent Claim
210 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample; reading an error detection coded signal from said device indicative of variations among a plurality of said devices which may affect said determination; decoding said error detection coded signal; and adjusting said determination in response to said error detection encoded signal.
Claim 20
Independent Claim
210 words
A method for measuring an activity or determining an analyte in a fluid medium employing a device comprising at least one capillary unit acting as the motive force for moving the fluid medium in the device, at least one chamber unit, an inlet port, an outlet port distant from the inlet port, and a reagent contained within the device, said reagent being a member of a detection system, wherein said capillary acts as a metering pump and flow controller of the assay medium through said device to provide for a time controlled reaction with said reagent, said method comprising: introducing a fluid sample though said inlet port into one of said units and allowing said fluid sample to transit from one unit to the next unit at a rate controlled by said capillary unit and react with said reagent resulting in a detectable signal produced by said detection system; determining said signal as a measure of said activity or the presence or concentration of said analyte in said sample; reading an error detection coded signal from said device indicative of variations among a plurality of said devices which may affect said determination; decoding said error detection coded signal; and adjusting said determination in response to said error detection encoded signal.
Claim 21
Dependent Claim
15 words
A method as in Claim 16, wherein said error detection signal employs a Hamming code.
Claim 22
Dependent Claim
16 words
A method as in Claim 16, wherein said error detection coded signal is an optical signal.
Claim 23
Dependent Claim
30 words
A method as in Claim 18, which further comprises the step of measuring the level of ambient light to determine if said error detection encoded signal can be accurately read.
References Cited (Backward Citations)
No citation records indexed.
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