1. Analytical Chemistry Department, GUIA Group, I3A, University of Zaragoza, Ma de Luna 3, 50018 Zaragoza, Spain
2. Samtack Adhesivos Industriales, C/Cerámica,
no. 3, Pol. Magarola, 08292 Esparreguera, Barcelona, Spain
3. Waters Corporation, Wilmslow SK9 4AX, United Kingdom