Three-dimensional ZnS/MoS2 on cellulose paper for determination of Digoxin in urine and plasma

The current study describes the in-situ growth of ZnS/MoS2 on cellulose paper using the thin-film microextraction (TFME) method. On cellulose paper, ZnS/MoS2 was grown using a simple, easy, and inexpensive hydrothermal method. The digoxin was quantified after TFME using high-performance liquid chromatography-UV detection (HPLC-UV). The effect of effective parameters such as extraction time, extraction temperature, agitation speed, and sample ionic strength was investigated, and the best conditions were selected. Under ideal conditions, a calibration curve with good linearity (R2=0.987) and a low limit of detection (LOD) in the range of 0.01–100 ng mL-1 was obtained. The detection limits were 0.03 ng mL-1. For the digoxin, the relative standard deviations (RSDs) were 5.3%. The method was successfully applied to the study of urine and plasma. Relative recoveries were found to range between 96% and102 %. The proposed method provided a straightforward, efficient, and environmentally friendly way for determining digoxin in real-world samples.