Quantitative analysis of thiols in consumer products on a microfluidic CE chip with fluorescence detection

✍ Scribed by Tobias Revermann; Sebastian Götz; Uwe Karst

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 335 KB
• Volume: 28
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.200600419

✦ Synopsis

Abstract

A microchip CE‐based method for the quantification of the thiols mercaptoethanoic acid (MAA) and 2‐mercaptopropionic acid (2‐MPA) in depilatory cream and cold wave lotions was developed. The thiols were first derivatized with the fluorogenic reagent ammonium‐7‐fluorobenzo‐2‐oxa‐1,3‐diazole‐4‐sulfonate (SBD‐F). The derivatives were separated within only 20 s by microchip CE and detected by their fluorescence. Conventional CE with diode array detection and LC with fluorescence detection were used for validation. The internal standard 3‐mercaptopropionic acid (3‐MPA) provided RSDs of multiple injections of only 4% or less for the MCE approach. LOD is 2 μM, LOQ 6 μM, and the linear range comprises nearly three decades of concentration starting at the LOQ.