A new CE with contactless conductivity detection method for the determination of complex cationic compositions: Application to the analysis of pen inks

作者：Saiz Jorge^*; Martin Alberca Carlos; Thanh Duc Mai; Garcia Ruiz Carmen

来源：Electrophoresis, 2016, 37(21): 2896-2902.

DOI：10.1002/elps.201600220

• Capillary electrophoresis
• Cations
• Contactless conductivity detection
• Metals
• Pen inks

A CE with contactless conductivity detection methodology using a novel background electrolyte for the separation and determination of 17 metal cations (Cs+, Rb+, K+, Ca2+, Na+, Mg2+, Mn2+, Sr2+, Li+, Ba2+, Fe2+, Pb2+, Cd2+, Zn2+, Co2+, Cu2+ and Ni2+) and ammonium has been investigated. The buffer, based on lactic acid and beta-alanine, was experimentally compared with other two commonly used electrolytes, showing important improvements, such as shorter analysis times (<11 min), better electrophoretic resolutions and higher detectabilities for certain analytes, such as Fe2+ and Pb2+. The inclusion of other additives such as 18-Crown-6 and alpha-hydroxyisobutyric acid was studied in order to obtain the best separation of the analytes of interest. The optimised method was applied to the analysis of 11 water-based pen inks and the determination of their metal composition. The methodology was demonstrated for the comparison and differentiation of pen inks.

• 出版日期2016-10