Cathodic adsorptive stripping voltammetry of an anti-emetic agent Granisetron in pharmaceutical formulation and biological matrix

Abstract

Granisetron showed one well-defined reduction peak at Hanging Mercury Drop Electrode (HMDE) in the potential range from -1.3 to -1.5 V due to reduction of C=N bond. Solid-phase extraction technique was employed for extraction of Granisetron from spiked human plasma. Granisetron showed peak current enhancement of 4.45% at square-wave voltammetry and 5.33% at cyclic voltammetry as compared with the non stripping techniques. The proposed voltammetric method allowed quantification of Granisetron in pharmaceutical formulation over the target concentration range of 50-200 ng/mL with detection limit 13.63 ng/mL, whereas in human plasma 50-225 ng/mL with detection limit 11.75 ng/mL.

Keywords: Granisetron; Hanging mercury drop electrode; Human plasma; Pharmaceutical formulation; Solid-phase extraction; Voltammetry.

Figure 1

Chemical structure of Granisetron.

Figure 2

Cyclic voltammograms of Granisetron (100 ng/mL) at scan rate 25–200 mV/s (A) and plot of scan rate (υ, mV/s) vs. peak current (I_p, μA) (B).

Figure 3

Square-wave voltammograms of Granisetron (175 ng/mL) at t_acc 0.0 s (curve b), t_acc 50 s (curve c) and cyclic voltammograms at t_acc 0.0 s (curve e), t_acc 50 s (curve f) and blank (curves a & d).

Figure 4

The plot of E_acc/V vs. peak current (I_p) of Granisetron (100 ng/mL) in the potential range from 0.0V to −0.9 V (vs. Ag/AgCl).

Figure 5

Square-wave voltammograms of standard solution of Granisetron at concentration levels, 50–200 ng/mL (A, curves b–h), blank solution (A, curve a) and plot of concentration vs. peak current (B).

Figure 6

Square-wave voltammograms of Granisetron at concentration levels, 50–225 ng/mL (A, curves b–i), blank solution (A, curve a) and plot of concentration vs. peak current (B), extracted from human plasma through SPE.