Research Article

Analysis of Reaction between -Lipoic Acid and 2-Chloro-1-methylquinolinium Tetrafluoroborate Used as a Precolumn Derivatization Technique in Chromatographic Determination of -Lipoic Acid

Table 3

Assay results of the commercial lipoic acid dosage forms; .

Declared value/mgDetermined/mgAverage error/%

Direct spectrophotometric method298 ± 3.26±0.46
Spectrophotometric method based on derivatization reaction300 mg/capsule300.66 ± 2.87±0.23
HPLC method based on DHLA-CMQT product as precolumn derivatization reaction301.44 ± 2.63±0.48