The MnO2@tea polyphenols used as a sorbent in dispersive solid-phase extraction (DSPE) of methyl, ethyl, propyl, and butyl parabens from wastewater and cosmetic samples followed by HPLC-UV. After optimization using response surface methodology, the linearity and limits of detection were in the range of 0.1- 500 μg/L and 0.08-0.3 μg/L, respectively.
