Analytical Sciences


Abstract − Analytical Sciences, 23(4), 423 (2007).

Multicommuted Fluorometric Multiparameter Sensor for Simultaneous Determination of Naproxen and Salicylic Acid in Biological Fluids
Juan F. GARCÍA-REYES, Pilar ORTEGA-BARRALES, and Antonio MOLINA-DÍAZ
Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaén, Paraje Las Lagunillas, E-23071 Jaén, Spain
A combined approach based on solid-phase optosensing and multicommutation principles has been applied to develop a method for the simultaneous analysis of two pharmaceuticals (naproxen and salicylic acid) in biological fluids. The multicommuted flow-through optosensor was based on direct native fluorescence measurements of both analgesics using a non-polar sorbent (C18 silica gel) as a solid sensing zone. The flow system was controlled by Java-written home-made software and designed using three-way solenoid valves for an independent automated manipulation of sample and carrier solutions. Using an optimized sampling time, the method was calibrated in the range of 1 - 25 and 5 - 200 ng mL-1. The obtained detection limits were 0.3 and 1.3 ng mL-1 for naproxen and salicylic acid, respectively, with RSD (%) values of better than 2% for both analytes. The proposed methodology was successfully applied to urine, serum and pharmaceutical preparations. Recovery percentages ranging from 96.1 to 104% were obtained for both analytes.