In-Tube Solid-Phase Microextraction and Liquid Chromatography Using a Monolithic Column for the Selective Determination of Residual Ethylenediamine in Industrial Cationic Polymers

Abstract

The selective determination of the diamine ethylenediamine (EDA) in the presence of a higher amount of residual dimethylamine in cationic polymers has been developed. The strategy uses both a solution derivatization with a selective agent of primary amines such as o-phthaldialdehyde-N-acetyl-L-cysteine (OPA-NAC) and an in-tube solid-phase microextraction (IT-SPME) coupled to liquid chromatography (LC). A 70 cm long, 0.32 mm internal diameter, and 3 microm thick commercially available capillary column coated with 95% polydimethylsiloxane and 5% polydiphenylsiloxane was employed to replace the injection loop of a Rheodyne injection valve. A volume of 1 mL of derivatized sample was passed through the capillary, and 100 microL of water was later used for cleaning and filling the capillary. After, the injection was effected and the desorption of the derivative from the capillary was carried out in the dynamic mode using the mobile phase. Chromatographic separation was performed in less than 2 min using a monolithic silica column Onyx (100 mm x 3.0 mm i.d.) under isocratic conditions. The effect of several parameters affecting derivatization and IT-SPME was investigated. The quantification of EDA was realized over the range of 0.07-2 microg/mL with adequate linearity, accuracy, and reproducibility, and the limit of detection was 20 ng/mL. The method is rapid and low in cost, and sample handling and organic solvent consumption have been minimized. Its application to polymeric cationic surfactants used in water treatment allowed the selective quantification of residual EDA at low microgram per milliliter levels of concentration without off-line preconcentration.

Recent advances of in-tube solid-phase microextraction

“…As an example, residual dimethylamine and ethylenediamine in cationic polymers has been determined by in-tube SPME-HPLC-DAD. This method also included on-line derivatization of the target analyte, resulting in an in-tube SPMEassisted derivatization procedure [24,25]. The main advantages were simple automation, rapidity, low cost, low consumption of solvents and reduction of wastes.…”

Folic acid-modified laponite nanodisks for targeted anticancer drug delivery

“…The principle of this assay has been validated in the literature. [43][44][45] Zeta-potential and dynamic light scattering (DLS) measurements were carried out using a Zetasizer Nano ZS system (Malvern, Worcestershire, UK) equipped with a standard 633 nm laser. All experiments were done in triplicate.…”

Magnetism-Enhanced Monolith-Based In-Tube Solid Phase Microextraction

“…Among the SPME techniques, in-tube solid phase microextraction (IT-SPME) shows additional advantages such as automation and online coupling with the separation and detection instruments. On the basis of these advantages, IT-SPME has been widely used in environmental monitoring, food analysis, and other fields. , In IT-SPME, the core is the extractive phase which decides the extraction targets and performance. So far, several capillaries including wall-coated open tubular, sorbent-packed, porous monoliths, − and fiber-packed have been used as extractive phases of IT-SPME.…”

“…On the basis of these advantages, IT-SPME has been widely used in environmental monitoring, 2 food analysis, 3 and other fields. 4,5 In IT-SPME, the core is the extractive phase which decides the extraction targets and performance. So far, several capillaries including wall-coated open tubular, 6 sorbentpacked, 7 porous monoliths, 8−10 and fiber-packed 11 have been used as extractive phases of IT-SPME.…”