Development and Application of a Quantitative Fluorescence-Based Immunochromatographic Assay for Fumonisin B₁ in Maize

Abstract

A fluorescence-based immunochromatographic assay (ICA) for fumonisin B1 (FB1) that employs conjugates of fluorescent microspheres and monoclonal antibodies (FM-mAbs) as detection reporters is described. The ICA is based on the competitive reaction between FB1-bovine serum albumin (BSA; test line) and the target FB1 for binding to the FM-mAb conjugates. A limit of detection (LOD) for FB1 of 0.12 ng/mL was obtained, with an analytical working range of 0.25-2.0 ng/mL (corresponding to 250-2000 μg/kg in maize flour samples, according to the extraction procedure). The recoveries of the ICA to detect FB1 in maize samples ranged from 91.4 to 118.2%. A quantitative comparison of the fluorescence-based ICA and HPLC-MS/MS analysis of naturally contaminated maize samples indicated good agreement between the two methods (r(2) = 0.93). By replacing the target of interest, the FM-based ICA can easily be extended to other chemical contaminants and thus represents a versatile strategy for food safety analysis.

Nanoparticle-based lateral flow biosensors

“…Edwards and Baeumner (2006) and Khreich et al (2008) used liposomes to encapsulate fluorescent dyes, getting higher sensitivity when using larger particles, with limits of detection close to 20 pg/mL. Commercial fluorescent microspheres which can be used on LFSs also are available (Xie et al, 2014;Wang et al, 2014b;Zhou et al, 2014). Interestingly, Xie et al (2014) evaluated the optimal quantity of antibodies required to be conjugated with their microspheres and compared it with AuNPs, resulting that when using microspheres this quantity can be reduced four times; moreover, even using less quantity of antibodies in the labels, the sensitivity, the working range and the limit of detection are improved in comparison to AuNPs assays.…”

Rapid and quantitative detection of 4(5)-methylimidazole in caramel colours: A novel fluorescent-based immunochromatographic assay

“…The fluorescent intensity of test lines (F T ) and control lines (F C ) were recorded, the ratio of F T /F C was then calculated. 20 blank samples (only PBS solution) were analysed and recorded by the optical reader for the calculation of the limit of detection (LOD) and the limit of quantification (LOQ) (Majdinasab et al, 2015;Wang et al, 2014). The LOD and LOQ were calculated as three times and ten times of the standard deviation of the negative samples, respectively.…”

“…Regarding immunoassay, enzyme-linked immunosorbent assay (ELISA) and ICA are two well-known and established examples (Wang et al, 2014). Indirect competitive ELISA (ic-ELISA) method has been developed by Wu et al to detect 4-MI in caramels (Wu, Yu, & Kang, 2014).…”

“…But limits have been observed when ultra high sensitivity is required (Chiao, Shyu, Hu, Chiang, & Tang, 2004;Peng et al, 2007;Valecha, Sharma, & Devi, 1998;Wang et al, 2007). In recent years, fluorescent microspheres, instead of colloidal gold, have been developed and used in ICA format with increased sensitivity and accuracy (Majdinasab et al, 2015;Wang et al, 2014). For example, fluorescence-based ICA has been established for sulfamethazine and enrofloxacin residue detection (Chen et al, 2013;Huang et al, 2013).…”

An on-site, ultra-sensitive, quantitative sensing method for the determination of total aflatoxin in peanut and rice based on quantum dot nanobeads strip

“…It can also achieve a sensitive, low-cost determination for AFT, thereby guaranteeing the potential on-site application. Typically, the gold nanoparticle has been substantiated as an effective reporter for colorimetric detection, allowing the qualitative determination for mycotoxin with relatively high concentrations [10,11,12,13].Furthermore, to meet the requirements of detection of sensitive mycotoxins such as AFT, some quantitative test strip methods have been developed recently using various reporters, such as liposome-encapsulated dyes [14], magnetic nanogold microspheres [15],time-resolved fluorescence [16,17,18], up-converting phosphor [19], fluorescent microspheres [20], and quantum dots (QDs) [21,22,23].Owing to the intrinsically high sensitivity, the fluorescence-based strip could qualify application in food safety [9].The organic fluorescence could be hampered from the extensive application due to their inherent photobleaching, thus lowering the sensitivity. QDs have been proven as one of the optimum reporters.…”