Fig. 4From: Optimization of an efficient solid-phase enrichment medium for Salmonella detection using response surface methodologyVisual observation of the whole-sample solid-phase enrichment assay using the optimized H2S-producing medium: a prepared swab with no sample applied, b, c negative control (swabs with E. coli only), d, e swabs applied with 101 cells of Salmonella and 105 cells of E. coliBack to article page