Simultaneous detection of N-acetyl-l-cysteine and physiological low molecular mass thiols in plasma by capillary electrophoresis

Abstract

N-acetyl-L-cysteine (NAC) is a therapeutic drug widely used as mucolytic agent in the treatment of respiratory diseases. Recently it has been proposed that NAC administration may modify the plasma levels of low molecular weight thiols (LMW) like cysteine, homocysteine and glutathione, though it has been still debated if their plasma concentration increases or decreases during the therapy. Therefore research calls for methods able to analyze simultaneously NAC and the other plasma LMW thiols in order to evaluate if NAC is able to modify plasma thiols concentration and in particular to reduce homocysteine levels in hyperhomocysteinemia. In this paper we present a new capillary electrophoresis method that allows a baseline separation of plasma NAC from the physiological thiols. The proposed method has been utilized to measure the drug and the physiological LMW thiols in NAC administered chronic obstructive broncho-pneumopathy (COPB) disease patients.

Determination of glutathione and glutathione disulfide in biological samples: An in-depth review

“…This is especially important with CE in view of the small amounts of samples analyzed. All recent papers have employed exclusively 5-IAF [175][176][177][178][179][180][181] or 6-IAF (Fig. 4) [42] as fluorophores for the determination of GSH, HCys, Cys or CysGly.…”

“…4) [42] as fluorophores for the determination of GSH, HCys, Cys or CysGly. One investigator group added N-methyl-dglucamine (NMDG) to the running buffer in order to obtain a better resolution of the thiol peaks [175,[177][178][179][180][181]. By masking the silanol functionalities on the surface of the uncoated capillary wall, NMDG decreased the electroosmotic flow and permitted complete peak resolution [178].…”

Capillary electrophoresis in the evaluation of aminothiols in body fluids

“…The same research group has recently developed a CE-LIF method for the simultaneous evaluation of a cysteine derivate, namely NAC [89]. NAC is a therapeutic drug widely used as mucolytic agent in the treatment of respiratory diseases.…”

Use of capillary electrophoresis with chemiluminescence detection for sensitive determination of homocysteine

“…However, CE with UV detection has low sensitivity, and an extraction and enrichment procedure prior to analysis often is needful [17]. CE with laser induced fluorescence (LIF) detection has been also used in the detection of HCys [18][19][20]. LIF detection is the most sensitive detection scheme available for CE.…”