Rapid and efficient determination of phenylurea herbicides in edible and medicinal herbs by D-SPE method using a microporous metal-organic framework adsorbent.

A rapid and efficient method is highly desired for the determination of phenylurea herbicides (PUHs) in edible and medicinal herbs. Herein, we report a dispersive solid-phase extraction (d-SPE) method using a metal-organic framework Zn4O(NTB)2 as the adsorbent. The microporous Zn4O(NTB)2 can selectively extract targets while excluding matrix substances. Under optimized conditions, this method exhibits high sensitivity, with a limit of detections (LODs) and limits of quantification (LOQs) in the range of 0.09-0.32 ng mL-1 and 0.32-1.08 ng mL-1, respectively. Moreover, the recoveries reach the range of 69.8 %-83.3 % with relative standard deviations below 6.2 %. The optimized adsorption efficiency of PUHs can be rapidly achieved in a short time of 10 min. Additionally, the adsorbent can be facilely regenerated with methanol washing. Furthermore, computational simulations reveal the guest-host interactions involving hydrogen bonding, π-π stacking interactions, and Van der Waals interactions. Practically, the established method has been successfully validated for extracting PUHs from Dendrobium candidum and Ganoderma lucidum samples.