Determination of zinc (II) in pharmaceuticals based on a flow-through bulk optode

• Published in: Journal of pharmaceutical and biomedical analysis Vol. 29; no. 5; pp. 779 - 786
• Main Authors: Albero, M.I, Ortuño, J.A, Garcı́a, M.S, Sánchez-Pedreño, C, Expósito, R
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 31.07.2002; Elsevier Science
• Subjects: Analysis; Biological and medical sciences; Flow Injection Analysis; Flow-through optode; General pharmacology; Medical sciences; Optics and Photonics - instrumentation; Pharmaceutical Preparations - chemistry; Pharmaceuticals; Pharmacology. Drug treatments; Zinc - analysis; Zinc determination; Zinc determination; Flow-through optode; Pharmaceuticals; Drug; Analysis method; Zinc II; Optical sensor; Membrane; Chemical sensor; Photometry; Quantitative analysis; Reflectance; Flow injection; Heavy metal
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/S0731-7085(02)00173-5

A method based on flow injection (FI), was applied for the determination of Zn (II) using a flow-through bulk optode membrane that incorporates 1-(2-pyridylazo)-2-naphthol in a plasticized poly (vinyl chloride) membrane entrapped in a cellulose support. The calibration graph plotting the reflectance at 562 nm versus [Zn (II)] was linear in the range 0.16–3.27 mg l −1 (2.5×10 −6–5×10 −5 M) with a detection limit of 0.10 mg l −1. The variation coefficients of the sensor response for 0.33 mg l −1 of Zn (II) were ±0.11% for consecutive measurements ( n=10), ±0.19% between days ( n=5) and ±0.22% between different membranes ( n=6). The sensor can be readily regenerated with the same acetic/acetate carrier of pH 3.9. The FI method proposed was applied to the determination of zinc (II) in pharmaceuticals.