Microextraction combined with microderivatization for drug monitoring and protein modification analysis from limited blood volume using mass spectrometry

Abstract

In the clinic, ethosuximide is commonly used to treat generalized absence seizures but has recently been repurposed for other diseases. Because of adverse effects and drug interactions, high-throughput therapeutic drug monitoring of ethosuximide is necessary. Microextraction is a simple, effective, rapid, and low consumption of organic solvents method for sample preparation. In this study, microderivatization-increased detection (MDID)-combined microextraction was used to detect ethosuximide by mass spectrometry. Ethosuximide is a difficult to retain and ionize compound in the C18 nano-flow column and ionization interface, respectively. Hence, we developed a fast method for detecting ethosuximide in human plasma by using the MDID strategy (within 2 min). Chemical microderivatization parameters were studied and optimized to increase the sensitivity of ethosuximide detection at trace levels. The linear range for the analysis of ethosuximide in 10 μL plasma was 5-500 μg/mL with a coefficient of determination (r) ≥ 0.995. The precision and accuracy of intraday and interday analyses of ethosuximide were below 13.0%. Furthermore, modifications of major proteins in plasma and blood cells, induced by ethosuximide, were identified. The proposed method effectively utilizes microliter samples to detect drug plasma concentrations under suitable microextraction procedures toward the eco-friendly goal of low consumption of organic solvents. Graphical abstract ᅟ.

New Methods Used in Pharmacokinetics and Therapeutic Monitoring of the First and Newer Generations of Antiepileptic Drugs (AEDs)

“…Data presented in the review show that near 50% of the LC methods applied the high-resolution detection despite the technical problems with the stability of MS/MS response. The sensitivity connected with the high-resolution LC-MS/MS causes that deuterated analogues of the AEDs are used as effective internal standards even with very small differences in molecular mass as well as retention time [21,22,37,40,42,65,84,119,146,147,149,151,157,176,177]. There is still an increase in the full automatization of analytical determination of AEDs in order to decrease hands-on time as well as consumption of organic solvents, protect the natural environment and improve the analytical process in terms of accuracy, precision, repeatability, and sensitivity.…”

“…There is still an increase in the full automatization of analytical determination of AEDs in order to decrease hands-on time as well as consumption of organic solvents, protect the natural environment and improve the analytical process in terms of accuracy, precision, repeatability, and sensitivity. To realize the purpose also different microextraction techniques for AEDs analysis were developed, including ultrasound-assisted emulsification microextraction [47], MEPS [66,75,167], microextraction combined with micro-derivatization-increased detection (MDID) [40], DLLME [59,133]. Automatization was applied for the DBS extraction of VPA, PHB, PHT, CBZ and its active 10,11 epoxide [21].…”

“…Wu et al [40] developed a micro-LC method with MALDI-TOF mass spectrometer to determine ESM in very low, 10 µl human plasma after prior microextraction with 40 µL volume of toluene and microderivatization to increase detection. The ESM and its derivative were separated on narrow nanoflow columns.…”

Sensitive determination of ethosuximide in human fluids by electromembrane extraction coupled with high performance liquid chromatography ultraviolet spectroscopy

“…The findings of the proposed analysis method are compared with other methods reported to determine the amount of ETX in different biological samples. One may observe from Table 4, the proposed method enjoys from the lowest identification and quantification limit that competes with the costly methods on MS. [9,10,12,50] Applying the derivatizing agent in some of the reported methods increases the time of sample preparation, consumes more organic solvent, and requires additional steps for the analysis. [9,13,50] In addition, the need for high sample volume in some methods leads to patient non-acceptance.…”

“…There are different analytical methods for the quantification of ETX in biological matrix. These methods include gas chromatography (GC) with flame ionization detector or mass spectrometry (MS), high-performance liquid chromatography (HPLC) with Ultra-Violet (UV) or MS, and ultra-performance liquid chromatography (UPLC) with MS. [8][9][10][11][12][13][14] However, most of the published literature deals with the determination of ETX in plasma or serum samples, while few methods have been proposed for the saliva. Among the routine process of bioanalysis, sample preparation is the foremost step in cleaning a complex biological matrix.…”