A novel fully-automated magnetic stirring-assisted lab-in-syringe analytical procedure has been developed for the fast and efficient dispersive liquid-liquid microextraction (DLLME) of caffeine in coffee beverages. The procedure is based on the microextraction of caffeine with a minute amount of dichloromethane, isolating caffeine from the sample matrix with no further sample pretreatment. Selection of the relevant extraction parameters such as the dispersive solvent, proportion of aqueous/organic phase, pH and flow rates have been carefully evaluated.

Caffeine quantification was linear from 2 to 75 mg L⁻¹, with detection and quantification limits of 0.46 mg L⁻¹ and 1.54 mg L⁻¹, respectively. A coefficient of variation (n = 8; 5 mg L⁻¹) of a 2.1% and a sampling rate of 16 h⁻¹, were obtained. The procedure was satisfactorily applied to the determination of caffeine in brewed, instant and decaf coffee samples, being the results for the sample analysis validated using high-performance liquid chromatography.

Item Type:	Refereed Article
Keywords:	flow analysis, liquid-liquid extraction, lab-in-syringe, dispersive liquid-liquid microextraction, caffeine determination, spectrophotometry, UV detection, coffee beverages
Research Division:	Chemical Sciences
Research Group:	Analytical Chemistry
Research Field:	Flow Analysis
Objective Division:	Expanding Knowledge
Objective Group:	Expanding Knowledge
Objective Field:	Expanding Knowledge in the Chemical Sciences
UTAS Author:	Maya, F (Mr Fernando Maya Alejandro)
ID Code:	127840
Year Published:	2016
Web of Science® Times Cited:	22
Deposited By:	Chemistry
Deposited On:	2018-08-19
Last Modified:	2018-09-20
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