Rapid and Sensitive Detection of the Food Allergen Glycinin in Powdered Milk Using a Lateral Flow Colloidal Gold Immunoassay Strip Test

Abstract

A rapid immunochromatographic lateral flow test strip in a sandwich format was developed with the colloidal gold-labeled mouse antiglycinin monoclonal antibody (mAb) and rabbit antiglycinin polyclonal antibody (pAb) to specifically identify glycinin, a soybean allergen. The test strip is composed of a sample pad, a conjugate reagent pad, an absorbent pad, and a test membrane containing a control line and a test line. This test strip has high sensitivity, and results can be obtained within 10 min without sophisticated procedures. The limit of detection (LOD) of the test strip was calculated to be 0.69 mg/kg using an optical density scanner that measures relative optical density. The assay showed high specificity for glycinin, with no cross-reactions with other soybean proteins or other food allergens. The recoveries of the lateral flow test strip in detecting glycinin in powdered milk samples ranged between 80.5 and 89.9% with relative standard deviations of less than 5.29% (intra-assay) and 6.72% (interassay). Therefore, the test strip is useful as a quantitative, semiquantitative, or qualitative detection method for glycinin in powdered milk. In addition, the test strip can be used to detect glycinin in other processed foods and may be a valuable tool in identifying effective approaches for reducing the impact of glycinin.

Food Allergy

“…It is therefore useful to determine immunoassay sensitivity, specificity, and robustness for optimal assay performance. Until recently, dipstick (lateral flow device) immunoassays have been used for qualitative applications (Poms et al 2004, van Hengel 2007, and efforts have been reported to develop their quantitative counterparts (Zheng et al 2012, Wang et al 2015. Simple and rapid dipstick formats offer portability and operational ease.…”

Development of a gold nanoparticle-based strip assay for detection of clopidol in the chicken

“…IC 50 of the the mAb against CLOP was 0.275 ng/mL, LOD was 0.018 ng/mL, and the linear range of detection was from 0.032 ng/mL to 0.896 ng/mL. studies (Wang et al, 2020;Wang et al, 2015) have proven that the antibodies and pH are essential to the function of GNP-labeled anti-CLOP mAb conjugates. Thus, in this study, GNP solutions were tested at different pH values (4.5, 5.5, 6.5, 7.5, and 8.5).…”

Chromatographic Immunoassays: Strategies and Recent Developments in The Analysis of Drugs and Biological Agents

“…Other chromatographic sandwich immunoassays have been described for IL-5, anti-HCV antibodies, potato virus X, cardiac troponin and myoglobin [81][82][83][84]. Sandwich immunoassays have also been applied to the determination of allergens, bacteria and toxins in food [85][86][87][88][89].…”

“…For example, the use of nanomaterials, such as gold or silver nanoparticles, and quantum dots should continue to lead to new or enhanced detection methods and formats for these methods [19,[85][86][87][88][93][94][95][96][97][98][99][100]109]. The utilization of alternative supports, such as affinity monoliths, is also expected to continue [110][111][112][113][114][115][116].…”

“…The utilization of alternative supports, such as affinity monoliths, is also expected to continue [110][111][112][113][114][115][116]. In addition, further research is anticipated in the development of miniaturized chromatographic immunoassays that can be employed in microfluidic devices and portable or disposable devices [19,[26][27][28]30,[82][83][84][85][86][87][88]100,113,116]. These develop ments, in turn, should increase the range of applications for which chromatographic immunoassays can be used in areas that include clinical chemistry, pharmaceutical testing, drug development and biomedical research [7,8].…”