monocytogenes Bacteria captured by MyOne-2D12 or MyOne-3F8 were detected by the Belnacasan cost MAb-2D12-coated fiber-optic sensor (with MAb-2D12 as a reporter) and yielded signals of 18,230 ± 1,840 pA and 13,280 ± 2,890 pA, respectively (Figure  8). The MAb-3F8 fiber optic sensor (with

MAb-2D12 as a reporter) produced signals of 11,225 ± 2,860 pA and 8,890 ± 1,900 pA, respectively (Figure  8a). The fiber optic signal value for MyOne-2D12 and -3F8 captured L. monocytogenes was about 2 to 3-fold higher than the signals obtained from the LOD concentrations (3 × 102 CFU/ml) (Figure  7). These data indicate that L. monocytogenes detection using MAb-2D12 for IMS and a fiber optic sensor gave better results compared with those obtained using MAb-3F8. Figure 8 Fiber-optic-based detection of L. monocytogenes after immunomagnetic capture with MyOne-2D12 or MyOne-3F8 from (a) buffer, (b) soft cheese, or (c) hotdog samples. (a) Fibers

were coated with MAb-2D12 and 3F8. (b, c) Fibers were coated with MAb-2D12 only. Cy5-conjugated MAb-2D12 was used as a reporter in all experiments. Data (signals; pA) are the mean of 3 fibers. Bars marked with different letters are significantly different (P < 0.05). Blank, PBS only. In soft cheese-containing co-culture of L. monocytogenes and L. innocua, both MyOne-2D12 and MyOne-3F8 captured Luminespib bacteria and produced signals of 13,026 ± 2,710 pA and 12,620 ± 4,554 pA, respectively (Figure  8b). Bacteria captured with Dynabeads anti-Listeria gave the lowest fiber-optic signals (Figure  8b). In Listeria-inoculated hotdog samples, only MyOne-2D12 was used for IMS and assayed Carteolol HCl by fiber optic sensor. The signal from the sample containing both L. monocytogenes and L. innocua was 8,376 ± 2,448 pA, while that from L. monocytogenes- and L. innocua-inoculated food was 8,552 ± 4,363 pA and 2,549 ± 1,358 pA, respectively (Figure  8c). For both food samples, the fiber optic signal values for MyOne-2D12 and -3F8

captured L. monocytogenes but not the L. innocua were higher than the signals obtained from the LOD cell concentrations (3 × 102 CFU/ml) (Figure  7). Therefore, the IMS and fiber optic sensor can be used together for detection of L. monocytogenes from enriched food samples, even in presence of L. innocua or other bacteria. Real-time qPCR for validation Real-time qPCR targeting hlyA was used to quantify PMB-captured Listeria from hotdogs and goat’s cheese artificially contaminated with L. monocytogenes and L. innocua (Table  2). When IMS was applied to the cheese samples followed by qPCR, MyOne-2D12 showed cell counts that were 4 times higher than those of MyOne-3F8 and Dynabeads anti-Listeria. In hotdog samples, MyOne-2D12 produced cell counts that were 2–3 times higher than those of the other 2 types of beads.