Protein Chips for Detection of Salmonella spp. from Enrichment Culture.
Food pathogens are the cause of foodborne epidemics, therefore there is a need to detect the pathogens in food productions rapidly. A pre-enrichment culture followed by selective agar plating are standard detection methods. Molecular methods such as qPCR have provided a first rapid protocol for detection of pathogens within 24 h of enrichment culture. Biosensors also may provide a rapid tool to individuate a source of Salmonella contamination at early times of pre-enrichment culture. Forty mL of Salmonella spp. enrichment culture were processed by immunoseparation using the Pathatrix, as in AFNOR validated qPCR protocols. The Salmonella biosensor combined with immunoseparation showed a limit of detection of 100 bacteria/40 mL, with a 400 fold increase to previous results. qPCR analysis requires processing of bead-bound bacteria with lysis buffer and DNA clean up, with a limit of detection of 2 cfu/50 μL. Finally, a protein chip was developed and tested in screening and identification of 5 common pathogen species, Salmonella spp., E. coli, S. aureus, Campylobacter spp. and Listeria spp. The protein chip, with high specificity in species identification, is proposed to be integrated into a Lab-on-Chip system, for rapid and reproducible screening of Salmonella spp. and other pathogen species contaminating food productions.
CNR-ISPA, Institute of Sciences of Food Productions, via Monteroni km 7, 73100 Lecce, Italy. palmiro.poltronieri@ispa.cnr.it.
Palmiro
P
Poltronieri
Biotecgen, c/o Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy. f.cimaglia@biotecgen.it.
Fabio
F
Cimaglia
Biotecgen, c/o Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy. e.delorenzis@biotecgen.it.
Enrico
E
De Lorenzis
Biotecgen, c/o Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy. m.chiesa@biotecgen.it.
Maurizio
M
Chiesa
CNR-ISPA, Institute of Sciences of Food Productions, via Monteroni km 7, 73100 Lecce, Italy. valeria.mezzolla@ispa.cnr.it.
Valeria
V
Mezzolla
CNR-ISPA, Institute of Sciences of Food Productions, via Monteroni km 7, 73100 Lecce, Italy. Barbara.reca@ispa.cnr.it.
Ida Barbara
IB
Reca
D004926:Escherichia coli; D005516:Food Microbiology; D040081:Protein Array Analysis; D012475:Salmonella; D012680:Sensitivity and Specificity; D013211:Staphylococcus aureus
Salmonella spp.; antibody; biosensors; detection; food pathogens; identification; labelling