Figure 10

(A): Chromatograms of (a) the blank water sample, (b) spiked sample (300 ng/mL) without D-µ-SPE method, and (c) tartrazine extracted from real saffron sample spiked with 300 ng/mL of tartrazine by the D-µ-SPE-HPLC–PDA technique based on Fe SA-MOF@CNF at optimal extraction conditions (pH = 7.56, mass sorbent = 15 mg, contact time = 6 min, and tartrazine concentration = 300 ng/mL). (B): Calibration curve of tartrazine.