Analytical test device and method for use in medical diagnoses

An analytical test device for determining the presence of at least one analyte in a fluid sample, said device comprising:

• a dry porous carrier through which a sample can flow by capillary action;
• a sample delivery means through which the sample can be applied to the device and flow thereinto;
• a sample circulation channel which is closed at its terminal ends and which circumscribes an area of the carrier;
• at least one detection zone covering at least a segment of said area of the carrier, wherein at least a segment of the sample circulation channel conforms with a border of the detection zone and is in operative communication with said detection zone, across which border the sample is permitted to enter into the detection zone simultaneously from a plurality of different directions and to form a stream flowing away from said border, the detection zone containing at least one mobile, labelled specific binding reagent for the at least one analyte, which said at least one mobile, labelled specific binding reagent is capable of reacting with said at least one analyte to form at least one labelled complex which is capable of moving along with said stream;
• and
• at least one capture zone channel having an entrance end and a closed terminal end, the entrance end being in operative communication with the detection zone to permit said stream to flow from the detection zone into the capture zone channel, the distances between all points of said border and said entrance end being essentially the same, the capture zone channel containing at least one immobilized specific binding reagent, which at least one immobilized specific binding reagent is capable of reacting with and concentrating said at least one labelled complex to form at least one detectable reaction product.

A method for determining the presence of at least one analyte in a fluid sample comprising the sequential steps of:

• i) providing an analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:
• a) a dry porous carrier through which sample can flow by capillary action;
• b) at least one detection zone covering at least a segment of an area of said carrier, and a sample circulation channel in operative communication with said detection zone, such that said sample is permitted to enter from said sample circulation channel into said detection zone from a plurality of different directions, and said detection zone containing at least one mobile, labelled binding reagent for said at least one analyte, which mobile, labelled binding reagent is capable of reacting with said analyte to form a labelled complex;
• c) at least one capture zone channel having an entrance end which is in operative communication with the detection zone to permit sample to flow from the detection zone into the capture zone channel, the distances between all points where said sample is permitted to enter said detection zone and said entrance end being essentially the same, said capture zone channel containing at least one immobilized specific binding reagent, which immobilized specific binding reagent is capable of reacting and concentrating said labelled complex to form a detectable reaction product;
• ii) applying a quantity of said fluid sample to said detection zone;
• iii) permitting the fluid sample to flow from the detection zone from said plurality of different directions to the capture zone channel and any said analyte therein to form a detectable reaction product at said immobilized specific binding reagent in said capture zone channel;
• and
• iv) identifying the presence of said at least one analyte in said fluid sample by detecting said detectable reaction product at said immobilized specific binding reagent in said capture zone channel.

An analytical test device for determining the presence of at least one analyte in a fluid sample, said device comprising:

• a dry porous carrier;
• at least one detection zone covering at least a segment of an area of said carrier;
• a sample circulation channel in operative communication with said detection zone, the sample being permitted to enter from said sample circulation channel into said detection zone from a plurality of different directions;
• at least one capture zone channel having an entrance end which is in operative communication with the detection zone to permit sample to flow from the detection zone into the capture zone channel.

An analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:

• a dry porous carrier through which a sample can flow by capillary action;
• a sample delivery means through which the sample can be applied to the device and flow thereinto;
• a sample circulation channel in operative communication with said sample delivery means, which is closed at its terminal ends and which circumscribes an area of the carrier;
• at least one detection zone covering at least a segment of said area of the carrier, wherein at least a segment of the sample circulation channel conforms with a border of the detection zone and is in operative communication with said detection zone, across which border the sample is permitted to enter into the detection zone simultaneously from a plurality of different directions and to form a stream flowing away from said border, the detection zone containing at least one mobile, labelled specific binding reagent for the at least one analyte, which said at least one binding reagent is capable of reacting with said at least one analyte to form at least one labelled complex which is capable of moving along with said stream;
• and
• at least one capture zone channel having an entrance end and a closed terminal end, the entrance end being in operative communication with the detection zone to permit said stream to flow from the detection zone into the capture zone channel, the capture zone channel containing at least one immobilized specific binding reagent, which at least one binding reagent is capable of reacting with and concentrating said at least one labelled complex to form at least one detectable reaction product.

An analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:

• a dry porous carrier through which a sample can flow by capillary action;
• a sample delivery means through which the sample can be applied to the device and flow thereinto;
• a sample circulation channel in operative communication with said sample delivery means, which is closed at its terminal ends and which circumscribes an area of the carrier, said sample circulation channel being polygonal or forming part of a polygon;
• at least one detection zone covering at least a segment of said area of the carrier, wherein at least a segment of the sample circulation channel conforms with a border of the detection zone and is in operative communication with said detection zone, across which border the sample is permitted to enter into the detection zone simultaneously from a plurality of different directions and to form a stream flowing away from said border, the detection zone containing at least one mobile, labelled specific binding reagent for the at least one analyte, which said at least one binding reagent is capable of reacting with said at least one analyte to form at least one labelled complex which is capable of moving along with said stream;
• and
• at least one capture zone channel having an entrance end and a closed terminal end, the entrance end being in operative communication with the detection zone to permit said stream to flow from the detection zone into the capture zone channel, the capture zone channel containing at least one immobilized specific binding reagent, which at least one binding reagent is capable of reacting with and concentrating said at least one labelled complex to form at least one detectable reaction product.

An analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:

• a dry porous carrier through which a sample can flow by capillary action;
• a sample delivery means through which the sample can be applied to the device and flow thereinto;
• a sample circulation channel in operative communication with said sample delivery means, which is closed at its terminal ends and which circumscribes an area of the carrier, said sample circulation channel being rectangular or forming part of a rectangle;
• at least one detection zone covering at least a segment of said area of the carrier, wherein at least a segment of the sample circulation channel conforms with a border of the detection zone and is in operative communication with said detection zone, across which border the sample is permitted to enter into the detection zone simultaneously from a plurality of different directions and to form a stream flowing away from said border, the detection zone containing at least one mobile, labelled specific binding reagent for the at least one analyte, which said at least one binding reagent is capable of reacting with said at least one analyte to form at least one labelled complex which is capable of moving along with said stream;
• and
• at least one capture zone channel having an entrance end and a closed terminal end, the entrance end being in operative communication with the detection zone to permit said stream to flow from the detection zone into the capture zone channel, the capture zone channel containing at least one immobilized specific binding reagent, which at least one binding reagent is capable of reacting with and concentrating said at least one labelled complex to form at least one detectable reaction product.