Reverse phase dispersive liquid–liquid microextraction coupled to slotted quartz tube flame atomic absorption spectrometry as a new analytical strategy for trace determination of cadmium in fish and olive oil samples

[Display omitted] •A sensitive and accurate analytical method was developed for cadmium.•The optimized RP-DLLME method was used to preconcentrate the analyte from oil.•SQT with three exit holes was coupled to FAAS system to increase the signal/noise.•Percent recovery results were calculated between 95.6 and 105.3 %. In the present study, trace level of cadmium was determined by a new, sensitive and simple analytical method called as reverse phase dispersive liquid–liquid microextraction (RP-DLLME) combined to slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS) system. Microextraction parameters such as type and volume of disperser solvent, volume of extraction solvent, heating effect, initial sample volume, final volume, centrifugation period and type/period of mixing were optimized. FAAS and SQT-FAAS systems were also examined to get high signal to noise ratio. After optimizing all significant parameters, the limit of detection (LOD) and limit of quantification (LOQ) of the developed analytical strategy were calculated as 0.74 and 2.48 μg/kg, respectively. In order to determine the applicability and accuracy of the RP-DLLME-SQT-FAAS method, recovery studies were performed in fish oil syrup. Matrix matching calibration strategy was used to eliminate heavy matrix effects on analytical signals, and percent recovery results were found between 95.6 and 105.7 %.