Lateral flow device

Detection of proteins that are responsible for the altered phenotype, using (a) enzyme-linked immunosorbent assays (ELISA), and (b) lateral flow devices. 

Analytical tools to detect this particular protein rely on the use of antibodies, which specifically recognize the newly introduced protein. Two major applications are available lateral flow devices (also known as strip test or dipstick), and ELISA. An overview and an in-depth discussion of protein-based methods for the detection of grain derived from modern biotechnology can be found in the literature e.g., [3,4],... 

Nanoparticles, e.g., silicon, gold, silver (Dequaire et al., 2000), are often used as materials for protein labeling in immunoassays, especially in lateral flow device (LFD), where they are responsible for visualization of the results. Their advantage lies in the fact that they enhance the optical signal, and reduce the background interference (Schneider et al., 2000 Lochner et al., 2003 Matveeva et al., 2005 Chumbimuni-Torres et al., 2006 Li et al., 1999 Peng et al., 2007a). 

Volume 504 describes various electrochemical and mechanical detectors, lateral flow devices, and ligands for biosensors. As in Vol. 503, we describe several direct measurement sensors (in Part I), indirect methods (Parts II-III). Ligands are described in Part IV and two related technologies are described in Part V. 

Latex and nanogoldparticles. Latex particles are sold in a variety of colors that can be visualized with the naked eye. Nanogold particles can be used alone or in combination with silver to increase sensitivity. Both t) pes of particles are commonly used in rapid immunoassays such us lateral flow devices. 

Lateral flow devices (LFDs) are user-friendly tests that have been used successfully for years to monitor pregnancy and drug abuse. New applications in the analysis of different analytes in foods have also increased in recent years, including testing for food allergens and gluten residues in foods. 

Van Herwijnen R, Baumgartner S (2006). The use of lateral flow devices to detect food allergens. In Koppelman SJ, Hefle SL (eds.), Detecting Allergens in Food. Woodhead Publishing, Cambridge, UK, pp. 175-181. 

TABLE 20.6 Specifications of Currently Available Lateral Flow Devices for Nut Allergen Control"... 

FIGURE 20.1 Construction of a lateral flow device. C, control line T, test line antibody conjugate. 

A wide variety of commercial LFIA kits for the detection of antibiotic residues is available and the most well-characterised of these are summarized in Table 5.4, including the rapid one-step assay (ROSA) range from Charm Sciences Inc., and the Tetrasensor, Twinsensor, Trisensor, and Sulfasensor from Unisensor SA and the Betastar from Neogen Corporation. Other LFIA assays have been reported in the scientific literature for the detection of antimicrobial residues, including a lateral-flow device for nicarbazin detection in animal feedstuffs. However, at present these are not commercially available. These LFIA tests incorporate either a receptor protein or an antibody as the specific capture molecule and operate in the competitive assay format (most applicable for small-molecule detection). The sample preparation protocols are based on either direct analysis of the liquid sample (e.g., milk) or a simple extraction step for solid or complex matrices using buffer(s) supplied in the test kit. In general, the time required to perform these tests is less than 30 min with only basic laboratory equipment, if any, required. 

Campbell K, Eodey T, Elint J, Danks C, Danaher M, O Keeffe M, Kennedy DG, Elliott C, Development and vahdation of a lateral flow device for the detection of nicarbazin contamination in poultry feeds, J. Agric. Food Chem. 2007 55 2497-2503. 

Dry tests or test strips (also called lateral flow devices or immunomigration strips) are popular as... 

Antibodies have been produced to both retronecine and monocrotaline and detected using an avidin-biotin antibody. Retronecine was obtained from the hydrolysis of monocrotaline, succinylated and coupled to bovine serum albumin or ovalbumin. Recently an ELISA lateral flow device (dipstick test) based on gold colloidal polyclonal antibodies has been developed for jacobine and lycopsamine in honey and animal feed [59]. 

Lateral-flow devices are among the most-established POCT platforms as they fulfill most of the aforementioned characteristics of an ideal POC platform. The idealized concept of a biosensor (Fig. 1.6)" in POC applications includes a transducer coupled with a recognition element. The recognition event is then converted into a useful analytical signal (mainly electrochemical or colorimetric). The recognition elements include proteins, nucleic acids, and many more as elaborated in Section 1.3. 

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