Potentiometric determination of acetylsalicylic acid by sequential injection analysis (SIA) using a tubular salicylate-selective electrode

• Type: Article in International Scientific Journal
• Date: 2001

Authors

Pasekova, H (Author) Other; Sales, MG (Author) Other; Montenegro, MC (Author) FFUP; Araujo, AN (Author) FFUP; Polasek, M (Author) Other

Journal

Title: Journal of Pharmaceutical and Biomedical Analysis

Vol. 24

Pages: 1027-1036

ISSN: 0731-7085

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 26 Citations

Scopus - 31 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-000-W9Q

DOI: 10.1016/s0731-7085(00)00537-9

Abstract (EN): This paper deals with the development of an automated procedure for formulation assays and dissolution tests based on a sequential injection analysis (SIA) system involving an ion-selective electrode as sensing device. Construction of a tubular salicylate (Sal) selective electrode suitable for potentiometric determination of acetylsalicylic acid (Asa) in pharmaceutical formulations is described. The flow-through electrode is formed by a PVC membrane containing 29.2% (w/w) PVC, 5.8% (w/w) tetraoctylammonium salicylate (ionic sensor), 58.5% o-nitrophenyloctylether (plasticizer) and 6.5% (w/w) p-tert-octylphenol (stabilising, additive which increases electrode selectivity). The calibration range is 0.05-10 mM Sal, the limit of detection (LOD) is 0.05 mM Sal, the slope is 56.0 mV per decade at 22 degreesC. The R.S.D. is 0.20% (15 readings) when determining 2.5 mM Sal in standard solution. The electrode is used fur sensing Asa after. its on-line chemical hydrolysis to Sal in a SIA system. The sampling rate is 6 h(-1) but for the dissolution tests the frequency is increased to 20 h(-1). The SIA set-up is employed for the assay of Asa in plain tablets, composed tablets and effervescent tablets and for performing dissolution tests of normal and sustained release tablets. Results obtained by this technique compare well with those required by the US Pharmacopoeia XXIV. (C) 2001 Elsevier Science B.V. All lights reserved.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10