Abstract
A simple selective luminescent dependent approach was established for quantitation of two selective β2 agonists namely; Fenoterol hydrobromide (FEN) and Salmeterol xinafoate (SAL). This approach utilizes the capability of the cited drugs to undergo a complexation reaction with Europium ion (Eu3+) in the presence of 1,10-phenanthroline as a co-ligand. The resultant complex leads to a hypersensitive transition and enhancement of the Eu3+ emission peak at 615nm (279nm excitation). Under the optimized conditions, the rectilinear concentration plots of both drugs were (70–1500ngmL−1) and (100–2000ngmL−1) with limit of quantitation 51.3 and 84.4ngmL−1 for FEN and SAL, respectively. The luminescence properties of the complex and its optimum formation conditions were carefully investigated according to the regulations of ICH and the method was successfully applied in plasma. The good accuracy and selectivity of the suggested method allowed extending the proposed protocol into stability study of the cited drugs.
Suggested reaction mechanism between Fenoterol hydrobromide as a representative example and Eu3+ in presence of 1,10-phenanthroline. [Display omitted]
•Development of a new spectrofluorimetric method for quantitation of Fenoterol hydrobromide and Salmeterol xinafoate.•The method is based on the ability of the cited drugs to make complexes with Europium in presence of 1,10-Phenanthroline.•Validation of the proposed method according to the ICH guidelines.•Application of the proposed method on different dosage forms and human plasma.•Application to stability studies at different stress conditions.