TiO₂ Nanoparticles Functionalized Monolithic Capillary Microextraction Online Coupled with Inductively Coupled Plasma Mass Spectrometry for the Analysis of Gd Ion and Gd-Based Contrast Agents in Human Urine

Abstract

In this work, a novel method of TiO2 nanoparticles (NPs) functionalized monolithic capillary microextraction (CME) online coupling with inductively coupled plasma mass spectrometry (ICPMS) was developed for the sequential determination of Gd(3+) and Gd-based contrast agents in human urine samples. The monolithic capillary was prepared by embedding anatase TiO2 NPS in the poly(methacrylic acid-ethylene glycol dimethacrylate) (MAA-EDMA) framework. The Gd(3+) and Gd-based contrast agents (such as gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) and Gd-DTPA-bismethylamide (Gd-DTPA-BMA)) display different adsorption behaviors on the prepared monolithic capillary which possesses the adsorption properties of both anatase TiO2 NPS and poly(MAA-EDMA) monolith. Under the optimized conditions, the limits of detection (LODs) were found to be 3.6, 3.2, and 4.5 ng L(-1) for Gd(3+), Gd-DTPA, and Gd-DTPA-BMA, respectively, which are the lowest up to date. The enrichment factor was 25-fold with the sample throughput of 5 h(-1). The proposed method was validated by the analysis of Gd(3+) and Gd-DTPA in the healthy human urine samples as well as Gd(3+) and Gd-DTPA-BMA in patient urine samples. It was found that only a small amount of the free Gd(3+) was released from Gd-DTPA-BMA, and accurate results could be obtained since no oxidation/reduction or subtraction is involved in this method. This method is simple, sensitive, and rapid and provides a very attractive nonchromatography strategy for the speciation of Gd(3+) and Gd-based contrast agents in urine samples.

Novel materials as capillary coatings for in‐tube solid‐phase microextraction for bioanalysis

“…Incorporation of nanomaterials (TiO 2 NPs, silica NPs, metal organic frameworks, graphene nanosheets, and CNTs) into polymeric monolithic columns has emerged as an effective way to afford higher specific surface area, thereby providing more active adsorption sites for target molecules and enhancing the capacity to extract the analytes [100][101][102].…”

Boronate affinity monolithic column incorporated with graphene oxide for the in‐tube solid‐phase microextraction of glycoproteins

“…And the SWNTs incorporated monolithic column showed higher preconcentration ability toward analytes. Polymeric monolith incorporated with ZnO nanoparticles , TiO 2 nanoparticles , graphene , and β‐cyclodextrin/graphene composites were also reported.…”

Facile Chip-Based Array Monolithic Microextraction System Online Coupled with ICPMS for Fast Analysis of Trace Heavy Metals in Biological Samples

“…The dual-model porous structure of the monolithic column provides lots of pathways for the flow liquid resulting in low back-pressure, and the large specific surface area with abundant functional groups is beneficial for extraction. Therefore, capillary monolithic microextraction has been successfully used for the analysis of organic compounds, , biomolecules, , and trace metals. − Liu et al prepared a poly­(glycidyl methacrylate- co -ethylene glycol dimethacrylate) (poly­(GMA- co -EDMA)) capillary monolithic column with sulfydryl functional groups and developed an online capillary monolith microextraction-ICPMS method for the determination of trace Au and Pb in human urine and serum; the LODs were 5.8–8.3 ng L –1 . The same authors also modified a poly­(methacrylic acid (MAA)- co -EDMA) capillary monolithic column with TiO 2 nanoparticles and established a new method of online capillary monolithic microextraction-ICPMS for the analysis of free Gd 3+ and Gd-based contrast agent in human urine with LODs of 3.2–4.5 ng L –1 .…”