Multicommuted Fluorometric Multiparameter Sensor for Simultaneous Determination of Naproxen and Salicylic Acid in Biological Fluids

Abstract

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.

Multicommutation in Flow Systems: A Useful Tool for Pharmaceutical and Clinical Analysis

“…In the latter case, the separation of the analytes can be made using a mini-column filled with the same solid support used in the flow-through cell [30,31] or in the same flow-through cell [32,33]. When the retention/desorption kinetic of the analytes on the solid support is very different, the separation can be performed by just placing an extra amount of microbeads in the flow-though cell.…”

“…The same configuration of valves is used, but the mini-column is removed from the flow system. This manifold was used for the fluorimetric determination of naproxen/salicylic acid in biological fluids [32] and pyridoxine/riboflavin in pharmaceuticals [33].…”