Micro solid phase extraction of parabens from breast milk samples using Mg-Al layered double hydroxide functionalized partially reduced graphene oxide nanocomposite.

In this study, a magnesium-aluminum layered double hydroxide coated on graphene oxide nanosheets was synthesized. It was successfully applied as an effective medium for determination of the parabens in human breast milk samples using micro solid phase extraction by packed sorbent (in spinal syringe format) followed by HPLC-UV. Effective parameters were optimized by central composite design. Under the optimal conditions, figures of merit of the developed method were obtained in which the limits of detection were found between 3.0 and 5.0 µg L-1. The calibration plots were linear in the range of 10-1000 µg L-1. Intra- and inter-day RSD% (n = 3) at two concentration levels of 25 and 250 µg L-1 varied between 4.2 and 9.5%. The relative recovery values for the spiked breast milk samples were in the acceptable range of 87.2-104.4%. Accordingly, the proposed method exhibits proper sensitivity, good repeatability, and acceptable applicability for the determination of parabens in complex matrices.