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A new optical sensor was developed for rapid screening with high sensitivity for the existence of biogenic amines (BAs) in poultry meat samples. Gold nanoparticles (GNPs) with particle size 11–19 nm function as a fast and sensitive biosensor for detection of histamine resulting from bacterial decarboxylation of histidine as a spoilage marker for stored poultry meat. Upon reaction with histamine, the red color of the GNPs converted into deep blue. The appearance of blue color favorably coincides with the concentration of BAs that can induce symptoms of poisoning. This biosensor enables a semi-quantitative detection of analyte in real samples by eye-vision. Quality evaluation is carried out by measuring histamine and histidine using different analytical techniques such as UV–vis, FTIR, and fluorescence spectroscopy as well as TEM. A rapid quantitative readout of samples by UV–vis and fluorescence methods with standard instrumentation were proposed in a short time unlike chromatographic and electrophoretic methods. Sensitivity and limit of detection (LOD) of 6.59 × 10−4 and 0.6 μM, respectively, are determined for histamine as a spoilage marker with a correlation coefficient (R 2) of 0.993.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-017-2014-z) contains supplementary material, which is available to authorized users.

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Schiff bases of acetylacetone, benzoylacetone, dibenzoylmethane, and thienoyltri¯uoro-acetone with ethanolamine and 2-aminophenol were synthesized and characterized by elemental analysis, infrared and 1 H NMR spectra. Dissociation constants of the synthesized ligands were determined in methanol-water and at an ionic strength of 0.1 M KNO 3 at different temperatures; the associated thermodynamic parameters were calculated. Single crystals of one of the ligands were prepared; the X-ray diffraction pattern was analyzed. Thermal analyses of the investigated ligands were performed and correlated with the ligand structure.

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