Analytical features of the MSPE-HPLC-UV method^a.

Analyte	LOD	LOQ	Linear range	R 2	EFb	RSD (%) (within day)c	RSD (%) (between day)c
F	1.0	3.0	3.0–400	0.9971	125	5.2	10.8
HMF	2.0	7.0	7.0–500	0.9945	113	6.4	9.1

^aAll concentrations are based on μg kg⁻¹.

^bEnhancement factor.

^cRelative standard deviations (n = 5 samples for within day and n = 3 days for between day) were obtained at a 20 μg kg⁻¹ level of the furfurals.