Determination of Lead Employing Simple Flow Injection AAS with Monolithic Alginate-Polyurethane Composite Packed In-Valve Column

• Published in: Molecules (Basel, Switzerland) Vol. 26; no. 15; p. 4397
• Main Authors: Issarangkura Na Ayutthaya, Piyanat, Yeerum, Chonnipa, Kesonkan, Kullapon, Kiwfo, Kanokwan, Grudpan, Kate, Teshima, Norio, Murakami, Hiroya, Vongboot, Monnapat
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 21.07.2021; MDPI
• Subjects: Acids; alginate-polyurethane composite; Alginic acid; Automation; Binding sites; Calibration; Diisocyanates; FlameAAS; flow injection; Flow velocity; in-valve column; Injection; Laboratories; Lead content; lead(II); Load distribution; monolithic column; Polyurethane; Polyurethane resins; Scientific imaging; Sodium alginate; Voltammetry
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules26154397

A simple flow injection FlameAAS for lead determination with an alginate-polyurethane composite (ALG-PUC) monolithic in-valve column has been developed. The ALG-PUC monolithic rod was prepared by mixing methylene diphenyl diisocyanate with polyol and sodium alginate with the ratio of 2:1:1 by weight for a 5 min polymerization reaction. It was then put into a column (0.8 cm i.d × 11 cm length) situated in a switching valve for the FI set up. A single standard calibration could be obtained by plotting the loaded µg Pb2+ vs. FI response (absorbances). The loaded µg Pb2+ is calculated: μg Pb2+ = FRload × LT × CPb2+, where the FR load is the flow rate of the loading analyte solution (mL min−1), LT is the loading time (min), and CPb2+ is the Pb2+ concentration (µg mL−1). A linear calibration equation was obtained: FI response (absorbances) = 0.0018 [µg Pb2+] + 0.0032, R2 = 0.9927 for 1–150 µg Pb2+, and RSD of less than 20% was also obtained. Application of the developed procedure has been demonstrated in real samples.