Lateral Flow Assay: A World of Possibilities for the Diagnostic

Review Article

Austin Clin Microbiol. 2019; 3(1): 1010.

Lateral Flow Assay: A World of Possibilities for the Diagnostic

Contreras MEM*

Parasite Enzymology Laboratory, University of the Andes, Venezuela

*Corresponding author: María Elizabeth Márquez Contreras, Parasite Enzymology Laboratory, University of the Andes, Faculty of Science, Mérida, Venezuela

Received: June 18, 2019; Accepted: July 08, 2019;Published: July 15, 2019


Lateral Flow Assays (LFAs) are devices that have acquired a great popularity worldwide because of their ergonomic design; do not require refrigeration for storage. As well as, are easy to use, this facilitates its manipulation by non-specialized personnel; provide results in a short period, which is very advantageous in modern times. In addition, these tests can be acquired by people of low economic resources, due to their relatively low costs; they provide very reliable results and have great sensitivity and specificity; among many other positive properties. The LFA format consists of several components: 1) sample pad is the placement area of the sample; 2) conjugate pad contains the component of interaction with the positive sample associated with the reporter labels; 3) nitrocellulose membrane chemically treated to produce a test line and/or control line, which are the indicators of a positive or negative sample. The reporter labels are varied: colloidal gold, enzymes, colored latex beads, quantum dots, carbon nanoparticles and their use depends on the requirements of each test in particular. This review focuses on the general aspects of these rapid tests of great utility in multiple areas of life such as: clinical diagnosis, veterinary, agriculture, biowarfare, food analysis, environmental health and safety, industrial testing, as well as in new areas that have arisen more recently, such as molecular diagnostics and theranostics


Lateral flow assays (LFA), also called Rapid Test Devices (RTD), are tools based on chromatography whose principle is very simple: the test sample is placed in the sample pad to determine the presence or absence of the particular analyte, then the displacement lateral occurs through capillary action to reach the conjugate pad where the analyte binds to the reporter label, these molecules continue to migrate until they come the Control Lines (LC) and the Test Line (TL), then the liquid continues travel until the absorbent pad. The LC is an internal control of these tests and must always provide a signal (which allows corroborating the correct operation) and TL indicates if the sample is positive (presence of signal) or negative (absence of signal); in the case of a positive sample this process promotes an interaction chemical that generates a signal indicative of reaction, such as the appearance of color [1].

Some outstanding advantages and disadvantages of LFA are shown in Table 1.

Citation:Contreras MEM. Lateral Flow Assay: A World of Possibilities for the Diagnostic. Austin Clin Microbiol. 2019; 3(1): 1010.