Development of a fluorimetric sequential injection analysis (SIA) methodology for determination of quinine

Author(s)

Infante, Carlos M. C. ^[1] ; Masini, Jorge C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim, BR-05508000 Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 22, n. 10, p. 1888-1893, 2011.
• Web of Science Citations: 2

Abstract

A sequential injection analysis (SIA) methodology was developed for fluorimetric determination of quinine in soft drinks. Minimum dispersion and efficient mixing were achieved by aspirating 200 mL of sample between two 100 mL reagent zones (0.10 mol L-1 H2SO4) at flow rate of 250 mL s-1 and using a reaction coil length of 50 cm (0.8 mm internal diameter). Linear response for quinine concentrations (C) between 0.050 and 100.0 mg L-1 was described by: I = (532 ± 40) + (2.36 ± 0.04) C, with r = 0.999, where I is the relative fluorescence intensity. The coefficient of variation and limits of detection and quantification were 1.9% (0.50 mg L-1 n = 10), 2.3 and 4.5 mg L-1, respectively. The sampling throughput was 60 analyses per hour, consuming 2.2 mL of concentrated H2SO4 and producing 4 mL of wastes per analysis. No statistically significant differences were observed between the results obtained by the proposed SIA methodology and the ones obtained by the batch procedure. (AU)

• FAPESP's process: 08/09284-3 - Development of methodologies for determination of organic substances using Sequential Injection Analysis (SIA) and high performance liquid chromatography in monolithic columns
• Grantee: Carlos Martín Infante Córdova
• Support Opportunities: Scholarships in Brazil - Post-Doctoral