Nickel oxide nanoparticles modified with dimethylglyoxime grafted on a cellulose surface as an efficient adsorbent for thin film microextraction of tramadol in biological fluids followed by its determination using HPLC.

In the current study, nickel oxide nanoparticles (NiO NPs) modified with dimethylglyoxime (DMG) were deposited onto the cellulose surface (Ni(DMG)-NiO-Cell) and used as an efficient adsorbent for thin film microextraction (TFME) of tramadol (TRA). The extracted TRA was determined using a high-performance liquid chromatography-ultraviolet detector (HPLC-UV). NiO NPs were synthesized by co-precipitation method on the surface of the cellulose substrate; afterward, its surface was modified by DMG to increase the extraction capability of the thin film toward TRA.