Dispersive Micro-Solid Phase Extraction for Sensitive Determination of Methotrexate from Human Saliva Followed by Spectrophotometric Method

For biological assessing of hospital personnel occupationally exposed to antineoplastic drugs, highly sensitive and accurate methods are required. Methotrexate (MTX) is an anticancer agent that is widely used in a variety of human cancers. For the first time, dispersive-micro solid phase extraction (D-µ-SPE) has been applied for determination of low levels of MTX in saliva samples. The method is based on rapid extraction of MTX using graphene oxide adsorbent. The sample preparation time is decreased by the fact that the adsorbent dispersed in the sample solution and extraction equilibrium can be reached very fast. This significant feature which obtained with this method is of key interest for routine trace laboratory analysis. The influence of different variables on D-µ-SPE was investigated. Under optimum conditions, the calibration graph was linear over the range of 10–1,000 ng/ml. The relative standard deviations are better than 9.0%. The proposed method was successfully applied for the determination of MTX in patient samples.