FIA-spectrophotometric assay of N-acetylcysteine by o-phthalaldehyde derivatization.
A flow injection-spectrophotometric procedure is proposed for the determination of N-acetylcysteine (NAC). The procedure is based on the rapid reaction of the thiol group with o-phthalaldehyde and isoleucine at pH 9.5 to give an 1-alkylthio-2-alkyl-substituted isoindole which shows maximum absorbance at 335 nm. The linear dynamic range is 16-160 micrograms/ml, with a 0.6% relative standard deviation for 100 micrograms/ml. The sampling rate is 126 samples/h. The method is applied successfully to the evaluation of NAC in commercial formulations.
Medina Hernández
M J
MJ
Departamento de Química Analítica, Facultad de Química, Universidad de Valencia, Spain.
García Alvarez-Coque
M C
MC
Bonet Domingo
E
E
Villanueva Camañas
R M
RM
D000111:Acetylcysteine / Q000032:analysis*; D007202:Indicators and Reagents; D011208:Powders; D012996:Solutions; D013053:Spectrophotometry; D009764:o-Phthalaldehyde / Q000737:chemistry
D007202:Indicators and Reagents; D011208:Powders; D012996:Solutions; D009764:o-Phthalaldehyde; D000111:Acetylcysteine