Particle agglutination detection method and device

Abstract

A method for detecting and / or observing particle agglutination comprising: placing a volume of particle suspension on a filter constructed to allow passage of individual particles; placing a volume of solution or suspension containing an agglutination reagent on the particle The location of the suspension; optionally placing the washing solution at the location of the agglutinating reagent; and observing the surface of the location for the presence of particles, which presence indicates that particle agglutination has occurred. Also provided are methods for detecting agglutination in general and hemagglutination, eg, for blood typing and cross-matching in particular. The method consists of continuous vertical addition of whole blood, blood typing reagents, and detergent to the filter. In the case of hemagglutination, colored, preferably red or reddish spots appear after washing. Devices and kits based on the present invention are also claimed which facilitate blood typing and cross matching in a non-laboratory environment without the need for laboratory instruments.

Description

field of invention [0001] The present invention relates generally to the detection of receptor-ligand interactions, and more particularly to the detection of blood group antigens and antibodies thereto for blood typing and matching purposes in transfusion medicine. Background of the invention [0002] Particle agglutination is a widely adopted immunological method for detecting and visualizing antigen-antibody interactions due to its simplicity, rapidity and relative sensitivity (Riochet 1993). Cells in general, and erythrocytes in particular, are particles that can be subjected to various methods of agglutination. Thus, erythrocyte agglutination (hemagglutination) is used in blood typing or matching as an important component of the pre-transfusion testing process to detect antigens on their surface and antibodies against such antigens (Rouger 1993; Brecher 2002). The purpose of pre-transfusion testing of blood is to prevent adverse reactions caused by hemagglutination or h...

AI Technical Summary

Problems solved by technology

Some drawbacks of this method include: (a) the need to mix for several minutes; (b) subjective visual results; (c) false positive reactions due to drying; and (d) inability to store slides

Some of the pitfalls of tube agglutination include: (a) the need for laboratory equipment, personnel, and environment; (b) subjective visual inspection of the results; (c) incorrect centrifugation speed or time may lead to false-positive or false-negative results, as possible Cell clumps considered immunoagglutinated; (d) no direct recording of results; (e) bulky tubes; and (f) risk of breakage and spillage

Drawbacks are: (a) require laboratory instruments, personnel and environment; b) do not record results directly; (c) bulky test hardware (even though the manufacturer calls the product a "card" it is actually in the holder series of test tubes, and not as flat as a "card"); and (d) complex preparation (inserting gel into narrow test tubes) resulting in high cost

Although the Akers device simplifies blood typing to such an extent that it can be used outside the laboratory (e.g., at the bedside) by non-blood bank professionals, it still has some disadvantages: (a) it requires a relatively large volume of blood; ( b) it requires the operator to record the timing of the steps; (c) it only allows for positive blood typing and not for crossmatch (observing the activity of the recipient's antibodies against the donor's red blood cells); (d) the appearance of the results may Can be misleading: the absence of red in the result window indicates a positive result, while red appears in a negative reaction result; and (e) the result must be observed exactly 1 minute after adding the saline wash

Although these products actually simplify the blood testing procedure to some extent, they are not completely error free and can be complicated for some personnel (Rachel and Plapp, 1990; Migeot et al., 2002)

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