Flow-injection chemiluminescence method to detect a β2 adrenergic agonist

A new method for the detection of (2) adrenergic agonists was developed based on the chemiluminescence (CL) reaction of (2) adrenergic agonist with potassium ferricyanide-luminol CL. The effect of (2) adrenergic agonists including isoprenaline hydrochloride, salbutamol sulfate, terbutaline sulfate and ractopamine on the CL intensity of potassium ferricyanide-luminol was discovered. Detection of the (2) adrenergic agonist was carried out in a flow system. Using uniform design experimentation, the influence factors of CL were optimized. The optimal experimental conditions were 1mmol/L of potassium ferricyanide, 10 mu mol/L of luminol, 1.2mmol/L of sodium hydroxide, a flow speed of 2.6mL/min and a distance of 1.2cm from Y-2' to the flow cell. The linear ranges and limit of detection were 10-100 and 5ng/mL for isoprenaline hydrochloride, 20-100 and 5ng/mL for salbutamol sulfate, 8-200 and 1ng/mL for terbutaline sulfate, 20-100 and 4ng/mL for ractopamine, respectively. The proposed method allowed 200 injections/h with excellent repeatability and precision. It was successfully applied to the determination of three (2) adrenergic agonists in commercial pharmaceutical formulations with recoveries in the range of 96.8-98.5%. The possible CL reaction mechanism of potassium ferricyanide-luminol-(2) adrenergic agonist was discussed from the UV/vis spectra. Copyright (c) 2014 John Wiley & Sons, Ltd.