Determination of ethambutol in biological samples using graphene oxide based dispersive solid-phase microextraction followed by ion mobility spectrometry

A simple, fast and reliable graphene oxide nanosheets based dispersive solid-phase microextraction methodology was described for the quantification of trace amount of ethambutol. The determination of ethambutol quantified with the aim of ion mobility spectroscopy as a sensitive, rapid, inexpensive and environmentally friendly instrument. Effects of relevant experimental parameters on the method efficiency such as pH, type of buffer and its volume, amount of absorbent, desorption solvent and extract time were investigated to reach the maximum efficiency of the proposed method. Under the optimum conditions, the calibration curve was linear in the range of 1 to 120 μg L−1 with the R-squared (R2) of 0.9990. The limit of detection for proposed method (n = 8) was 0.4 μg L−1 and the relative standard deviations were obtained (n = 8) 3.3% and 1.6% for 10 and 100 μg L−1, respectively. The proposed method was successfully applied for the preconcentration and determination of ethambutol in the different biological samples such as plasma, saliva, breast milk and artificial tear.