Determination of Reduced, Protein-Unbound, and Total Concentrations of N-Acetyl--cysteine and -Cysteine in Rat Plasma by Postcolumn Ligand Substitution High-Performance Liquid Chromatography

N-Acetylcysteine in the Prevention of Contrast-Induced Nephropathy

“…After intravenous injection, Harada et al found that NAC was highly bound to plasma and tissue proteins, forming various disulfide compounds. Only small amounts of NAC were found in circulation despite the intravenous route of administration (29). It is clear from these reports that, after oral administration, NAC is almost completely metabolized before entering the systemic circulation.…”

Practical Aspects of the Ligand-Binding and Enzymatic Properties of Human Serum Albumin.

“…For example, N-acetyl-L-cysteine (and L-cysteine) binds to albumin in plasma; the interaction can be quantitated by a high-performance liquid chromatographic (HPLC) method using hexaiodoplatinate. 36) Furthermore, D-penicillamine, 32,37) captopril, 32,33) meso-2,3-dimercaptosuccinate, 38) and SA3786 (a bucillamine derivative) 39) bind to albumin in the serum of patients receiving these drugs. Interestingly, the reactivity in patient sera is much higher than that found in albumin solutions 33) and in sera of healthy volunteers.…”

Molecular and nanoparticle postcolumn reagents for assay of low-molecular-mass biothiols using high-performance liquid chromatography

“…For the detection of the LMM biothiols, interferences from thioethers, thiazolidines and ascorbic acids have been reported [45]. However, Harada et al found that these interferences could be suppressed under certain experimental conditions [47]. The reaction medium used in their study is 0.1 M sodium phosphate buffer at pH 2.2 containing 100 mM H 2 PtCl 6 ·6H 2 O and 10 mM potassium iodide.…”

“…The reaction medium used in their study is 0.1 M sodium phosphate buffer at pH 2.2 containing 100 mM H 2 PtCl 6 ·6H 2 O and 10 mM potassium iodide. The derivatization was performed in a polyether ether ketone tube which was maintained at 40 • C. The method was used to determine three concentrations (reduced, protein-unbound, and total) of N-acetyl-l-cysteine and Cys in rat plasma with the detection limit of ∼20 pmol [47]. It was found that the reaction between hexaiodoplatinate and DTT leads to the formation of a contaminating substance that may be adsorbed to the inner walls of the HPLC pipeline and induce peak-broadening and tailing [47].…”

“…HPLC analysis of the LMM biothiols based on the optical changes following the substitution of the coordination bonds has been studied [45][46][47]. Hexaiodoplatinate exhibits a broad reactivity.…”