Piezoelectric detection of ion pairs between sulphonate and catecholamines for flow injection analysis of pharmaceutical preparations

• Published in: Talanta (Oxford) Vol. 48; no. 3; pp. 643 - 648
• Main Authors: Mo, Zhihong, Long, Xiaohui, Zhang, Minjuan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.1999; Oxford Elsevier
• Subjects: Analysis; Biological and medical sciences; Catecholamines; Flow injection; General pharmacology; Ion-pair; Medical sciences; Pharmacology. Drug treatments; Piezoelectric detection; Catecholamines; Ion-pair; Piezoelectric detection; Flow injection; Epinephrine(drug); Injectable form; Chemical analysis; Aminoacid; Piezoelectric detector; Ion pair; Dosage form; Tablet; Catecholamine; Dopa; Quantitative analysis
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/S0039-9140(98)00287-2

Fundamentals of ion-pair flow injection with piezoelectric detection were investigated experimentally and theoretically for the adsorption of dodecyl phenylsulfonate and interfacial ion-pair formation with epinephrine and l-dopa on silver electrode of quartz crystal microbalance. The influences of sulfonate concentration and operating parameters on the frequency response were demonstrated and provided the possibility for the discriminating determination of mixtures. The selected system of ion-pair flow injection with piezoelectric detection was applied to the determination of epinephrine and l-dopa. Calibration curves were linear in ranges 4.00–850 and 3.50–730 μg ml−1, with detection limits of 1.22 and 1.05 μg ml−1 and sampling frequencies of 120 samples h−1, for epinephrine and l-dopa, respectively. The method has been satisfactorily applied to the determination of catecholamines in pharmaceutical preparations.