Determination of histamine in tuna fish by photoluminescence sensing using thioglycolic acid modified cdte quantum dots and cationic solid phase extraction
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The determination of histamine based upon the photoluminescence static quenching of thioglycolic acid modified CdTe quantum dots (TGA-CdTe QDs) is proposed. Under optimum conditions, the analytical response followed a Stern-Volmer model. Experimental conditions were adjusted to enable a robust and reproducible analytical response. The linear response observed in the QDs aqueous dispersion covered the histamine concentration from 9.6×10−6 mol L−1 (1.1 µg mL−1) to 5.7×10−4 mol L−1 (63 µg mL−1). The approach was tested in the analysis of fresh and canned tuna fish samples after cationic solid phase extraction, in order to improve selectivity of determination. Analytical results of the eluted extracts were compared to the ones achieved with a reference spectrophotometric method using a concentration range that can be accessed by both methods and also by liquid chromatography with mass detection. Satisfactory recoveries were achieved for both canned and fresh tuna fish samples. The application in real samples has been demonstrated at the mg kg−1 level. The possible mechanism for histamine quenching is investigated.