S-quinolin-2-yl-methyldithiocarbazate-based magnetic adsorbent for magnetic solid-phase extraction of heavy metals from water samples

ABSTRACT

New S-quinolin-2-yl-methyl-dithiocarbazate-based magnetic adsorbent (MNP-SQ2MDTC) for magnetic solid phase extraction (MSPE) was developed for the determination of Cd²⁺ and Cu²⁺ in water samples. The surface of MNP was first coated with (3-aminopropyl) triethoxysilane (APTES) as cross-linker and then SQ2MDTC incorporated covalently to the coated MNP. The newly prepared MNP-SQ2MDTC was analysed by Fourier Transform infrared (FT-IR), X-ray diffractometer (XRD), energy dispersive X-ray spectroscopy (EDX), vibrating-sample magnetometry (VSM), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET). Under optimal MSPE conditions (20 mg adsorbent dispersed in 25 mL of sample which adjusted to pH 6.0 and sonicated for 10 min, before desorbed in 0.5 mL of 1 M HClO₄ and sonicated for 5 min), the validation method revealed a good linearity (0.1–5.0 µg mL⁻¹) with the coefficient of determination (R²) in the range of 0.995–0.996 for the samples. The limits of detection (LOD) of the developed method for Cd²⁺ and Cu²⁺ were found to be 0.054 and 0.040 µg mL⁻¹, and limit of quantification (LOQ) were 0.180 and 0.134 µg mL⁻¹, respectively. The recoveries of Cd²⁺ ranged from 75.6% to 93.9% and from 81.5% to 98.7% for Cu²⁺. To the best of our knowledge, this is the first study that have investigated the use of magnetic nanoparticles coated SQ2MDTC for determination of Cd²⁺ and Cu²⁺ in water samples analysis based on complexation of the metal ions to the surface of amino groups.

KEYWORDS:

• Magnetic nanoparticles
• Squinolin2ylmethyldithiocarbazate
• heavy metals removal
• magnetic solid phase extraction

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by funding from Universiti Sains Malaysia Research Grants (Short Term: 304.PKIMIA.6313334; Bridging: 304.PKIMIA.6316492) and International Islamic University Malaysia Research Initiative Grants (RIGS15-136-0136, P-RIGS18-029-0029).