title: Sensitive detection and quantification of gliadin contamination in gluten-free food with immunomagnetic beads based liposomal fluorescence immunoassay.
abstract: Gliadin from wheat is a common food allergen that can induce baker's asthma, wheat-dependent exercise-induced anaphylaxis, atopic dermatitis, and celiac disease. This gliadin assay focuses on rapidly screen and check for gluten contamination in raw materials and in the gluten-free food production process, not only for wheat-sensitive patients but also for the industries producing gluten-free foodstuffs. The developed assay incorporates the use of anti-gliadin antibody-conjugated immunomagnetic beads (IMBs) to capture the gliadin in samples and fluorescent dyes-loaded immunoliposomal nanovesicles (IMLNs) to produce and enhance the detection signal. Hence, a sandwich complex is formed as "IMBs-gliadin-IMLNs". Experimental results indicate that this detection platform exhibits good sensitivity for gliadin with a detection limit as low as 0.6 μg mL(-1) of gliadin; as the polyclonal antibody showed slight cross-reactions with barley and rye. Excellent recovery rates were found ranging from 83.5 to 102.6% as testing the spiked samples. Moreover, the CV (%) of intra- and inter-assay of this developed assay are 4.8-10.6% and 3.5-9.9%, respectively. Based on a parallel analysis of twenty food samples, the results of this developed assay provide a good consistency with those of an AOAC-approved ELISA kit without any false-negative results. The proposed assay method is thus a highly promising alternative method for detecting the contamination of gliadin in the food industry.
authors.affiliation: Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan, ROC.
authors.forename: Pei-Tzu
authors.initials: PT
authors.lastname: Chu
authors.forename: Hsiao-Wei
authors.initials: HW
authors.lastname: Wen
mesh_terms: D000818:Animals; D002645:Chickens; D055050:Diet, Gluten-Free / Q000592:standards; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005455:Fluorescent Antibody Technique / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D005903:Gliadin / Q000032:analysis*; D005983:Glutens / Q000032:analysis*; D018189:Immunomagnetic Separation / Q000379:methods*; D057230:Limit of Detection; D008081:Liposomes / Q000737:chemistry*
chemical_list: D008081:Liposomes; D005983:Glutens; D005903:Gliadin
keywords: Gliadin; Immunoliposomal nanovesicle; Immunomagnetic beads; Wheat allergen