Analysis of tetramethylene disulfotetramine in foods using solid-phase microextraction–gas chromatography–mass spectrometry

An automated solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS) method for the determination of tetramethylene disulfotetramine in foods was developed. A comparison of direct immersion (DI) and headspace (HS) extraction techniques using a 70 μm carbowax/divinylbenzene (CW/DVB) fiber is presented. The optimized DI-SPME method provided an aqueous extraction limit of detection (LOD) of 9.0 ng/g while the HS-SPME LOD was 2.7 ng/g. In both SPME modes, recovery was highly matrix dependent and quantification requires standard addition calibrations. Analysis of foods using DI-SPME encountered many obstacles including fiber fouling, low recovery and poor reproducibility. HS-SPME was successfully applied to food analysis with minimal interferences. Standard addition calibration curves for foods gave high linearity (R2 > 0.98), reproducibility (RSD < 12%) and sensitivity with LODs ranging from 0.9 to 4.3 ng/g.