High Sensitive Immunoassay for Multiplex Mycotoxin Detection with Photonic Crystal Microsphere Suspension Array

Abstract

A novel, sensitive, and high throughput competitive immunoassay for multiplex mycotoxins was established by immobilizing the artificial antigens (Ags) of mycotoxins on the surfaces of three kinds of silica photonic crystal microsphere (SPCM) suspension arrays. The SPCMs were encoded by their reflectance peak positions. Aflatoxin B1 (AFB1), fumonisin B1 (FB1), and citrinin (CIT) spiked in the cereals were extracted, and the fluorescein isothiocyanate (FITC) labeled antibodies (Abs) of these mycotoxins were added into the centrifuge tube which contained the SPCMs of the modified artificial antigens (Ags). The fluorescence signal was collected by an array fluorescent scanner. The limit of detection (LOD) was as low as 0.5, 1, and 0.8 pg/mL for AFB1, FB1, and CIT, respectively. The new method provided a wide linear detection range from 0.001 to 10, 0.001 to 10, and 0.001 to 1 ng/mL for AFB1, FB1, and CIT, respectively. The mean recovery rates are in range of 74.7 ± 4.0% to 127.9 ± 4.4% for the three mycotoxins in corn, peanuts, and wheat. The developed method for mycotoxins was used to assay the AFB1, FB1, and CIT level in 10 naturally contaminated cereal samples, and the results of detection were in agreement with that of a classic enzyme-linked immunosorbent assay (ELISA) method. This method saves a large amount of reagents (10 μL volume) and detection time (<3 h) for multiplex mycotoxin assay.

Simultaneous Detection of Ochratoxin A and Fumonisin B1 in Cereal Samples Using an Aptamer–Photonic Crystal Encoded Suspension Array

“…15,36 The fluorescence signal intensity was the 10 times higher than that obtained from the liquid system. 34 The comparison of the calibration curves of SPCMs with the same size diameter of glass beads was performed under the same conditions, which further demonstrated the above result ( Figure.S3).…”

“…14,15 In this paper, we established a new aptamer-based suspension array for simultaneous detection of ochratoxins A (OTA) and fumonisin B1 (FB1) in cereal samples using SPCMs as the encoded carriers. Ochratoxins A (OTA) and fumonisin B1 (FB1) are selected as a proof-of-concept that shows the capacity of the array to adapt the aptamer for a multiplex mycotoxin assay.…”

Microfluidic Synthesis of Barcode Particles for Multiplex Assays

“…With a sandwich format, the PCBs are used for multiplex detection of a series of targets, such as tumor protein markers, [162][163][164][165][166] tumor multidrug-resistance genes, [ 163 ] heart failure and coronary heart disease biomarkers, [ 168 ] environmental toxins, [ 169 ] and so on. [ 170,171 ] The PCBs in these groups all performed satisfactorily. For example, in the detection of multiplex tumor protein markers, the results indicated that the four targets, the α-fetoprotein (AFP), carcinoembryonic antigen (CEA), carcinoma antigen 125 (CA 125), and carcinoma antigen 19-9 (CA 19-9) could be assayed with limits of detection of 0.68 ng/mL, 0.95 ng/mL, 0.99 U/mL, and 2.30 U/mL, respectively.…”

Cell Microarray Technologies for High-Throughput Cell-Based Biosensors

“…However, there is still a possible disadvantage of QDs as a source of optical fluorescence because of their toxicity. To avoid this problem, Zhao et al and Deng et al have produced silica colloidal crystal beads (SCCBs) and silica photonic crystal microspheres (SPCM) as carriers for the suspension array (Figure 5b) [75,76]. Their end products generally share the common ideas: e.g., both groups have used silica nanoparticles as the fundamental material for microspheres.…”