1. a Department of Chemistry , Shandong University , Jinan, P. R. China
2. b Department of Analytical Chemistry , University of Almeria , La Canada de San Urbano, Almeria, Spain
3. c Pharmaceutical Analysis Laboratory, Biological and Medical Research Department (MBC‐03‐65) , King Faisal Specialist Hospital and Research Centre , P.O. Box 3354, Riyadh, 11211, Saudi Arabia