Cadmium determination in cola soft drinks via dispersive solid-phase microextraction using thiocarbanilide-functionalized carbon nanofibers

CARRIZO, BRIAN G.; FIORENTINI, EMILIANO F.; WUILLOUD, RODOLFO G.; VEGA, MABEL; ESCUDERO, LETICIA B.

JOURNAL OF FOOD COMPOSITION AND ANALYSIS

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2026 vol. 149

0889-1575

In this study, a new cadmium (Cd) microextraction and preconcentration system based on dispersive micro-solid phase extraction (D-μ-SPE), followed by HG-AFS detection, was efficiently developed. A novel adsorbent nanomaterial based on thiocarbanilide-modified carbon nanofibers (CNF@TC) was synthesized, characterized, and successfully incorporated into a preconcentration system for cadmium determination in bottled cola soft drink samples. The main factors affecting the extraction and back-extraction processes were evaluated. A 5 mg mass of CNF@TC was required to achieve 100 % Cd extraction using 40 mL of sample. A complete back-extraction was achieved using 500 μL of a 1:1 vol ratio HCl (37 % w/v)/H2O2 (30 % v/v) mixture. A competitive analytical performance was demonstrated, achieving a LOD of 0.120 μg/L, a linear range of 0.40–100 μg/L, and RSD% of 3.4 % (2.0 μg/L Cd, n = 6). A preconcentration factor of 57 was obtained. The accuracy of the proposed methodology was validated by analyzing a certified reference material and Cd-spiked samples, with recoveries from 96.0 % to 100 %. This work reports the first application of CNF@TC in dispersive micro solid phase extraction technique for trace Cd determination in cola bottled soft drinks.