ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Magnetic bio-coated nanoadsorbents for the extraction and spectrophotometric determination of ritodrine hydrochloride using Fe₃O₄@Citrulline@CTAB and Fe₃O₄@Alginate@CTAB

Israa Nabeel Hamzah and Hind Hadi

Department of Chemistry, College of Science, University of Baghdad, Baghdad, Iraq

E-mail: hind.h@sc.uobaghdad.edu.iq

Received: 30 January 2026  Accepted: 9 March 2026

Abstract:

The present work aims to develop a new bio-magnetic nanosorbent, Fe₃O₄@Citrulline@CTAB, and to compare its performance with Fe₃O₄@Alginate@CTAB for the removal of ritodrine hydrochloride (RIT) from aqueous solutions. Both bio-coated magnetic nanosorbents were prepared via an in-situ coprecipitation approach, in which Fe₃O₄ nanoparticles were first modified with either citrulline or sodium alginate and subsequently functionalized with cetyltrimethylammonium bromide (CTAB). Comprehensive physicochemical characterization confirmed the successful formation of magnetic nanocomposites. RIT was initially reacted with diazotized sulfamethazine to generate a rapidly developing, highly sensitive azo dye, facilitating its selective adsorption onto synthesized nanosorbents. Adsorption on both materials was mainly governed by polarity differences and electrostatic interactions between the azo dye and the functionalized magnetic surfaces. The nanosorbents exhibited remarkable extraction performance, with removal efficiencies of 92–95% and good linear calibration ranges of 0.1–4.0 µg/mL for Fe₃O₄@Citrulline@CTAB and 0.05–4.00 µg/mL for Fe₃O₄@Alginate@CTAB. The method demonstrated excellent precision and accuracy, with RSD values below 4% and relative recoveries ranging from 97.7 to 98.9%. Preconcentration factors of 57 and 56 were achieved for the two sorbents, respectively. The method was successfully applied to different environmental water samples and urine, confirming its robustness and reliable performance in complex matrices. The method provides a sensitive and eco-friendly approach for RIT monitoring in water systems, well suited to modern environmental analysis.

Keywords: Alginate; Citrulline; Dispersive solid phase microextraction; In-situ coprecipitation; Ritodrine; Spectrophotometry

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-04798-2

Chemical Papers 80 (6) 6783–6799 (2026)