Nonhydrolytic sol-gel approach to facile creation of surface-bonded zirconia organic-inorganic hybrid coatings for sample preparation. Ι. Capillary microextraction of catecholamine neurotransmitters

• Published in: Journal of chromatography. A Vol. 1468; p. 23
• Main Authors: Alhendal, Abdullah, Mengis, Stephanie, Matthews, Jacob, Malik, Abdul
• Format: Journal Article
• Language: English
• Published: Netherlands 14.10.2016
• Subjects: Catecholamines - isolation & purification; Chemistry Techniques, Analytical - instrumentation; Chemistry Techniques, Analytical - methods; Gels - chemistry; Neurotransmitter Agents - isolation & purification; Reproducibility of Results; Silicon Dioxide - chemistry; Zirconium - chemistry; pH stability; Desorption efficiency (DE); Catecholamines; Nonhydrolytic sol-gel approach; Surface-bonded zirconia-polypropylene oxide sorbent coatings; Capillary microextraction (CME)
• ISSN: 1873-3778

Nonhydrolytic sol-gel (NHSG) route was used for the creation of novel zirconia-polypropylene oxide (ZrO -PPO) sol-gel hybrid sorbents in the form of surface coatings for the extraction and preconcentration of catecholamine neurotransmitters and molecules structurally related to their deaminated metabolites. In comparison to other sorbents made of inorganic transition metal oxides, the presented hybrid organic-inorganic sorbents facilitated reversible sorption properties that allowed for efficient desorption of the extracted analytes by LC-MS compatible mobile phases. The presented sol-gel hybrid sorbents effectively overcame the major drawbacks of traditional silica- or polymer-based sorbents by providing superior pH stability (pH range: 0-14), and a variety of intermolecular interactions. Nonaqueous sol-gel treatment of PPO with ZrCl was employed for the derivatization of the terminal hydroxyl groups on PPO, providing zirconium trichloride-containing end groups characterized by enhanced sol-gel reactivity. NHSG ZrO -PPO sorbent provided excellent microextraction performance for catecholamines, low detection limits (5.6-9.6pM), high run-to-run reproducibility (RSD 0.6-5.1%), high desorption efficiency (95.0-99.5%) and high enrichment factors (∼1480-2650) for dopamine and epinephrine, respectively, extracted from synthetic urine samples. The presented sol-gel sorbents provided effective alternative to conventional extraction media providing unique physicochemical characteristics and excellent extraction capability.