Determination of Urinary Hydroxyl PAHs Using Graphene Oxide@Diatomite Based Solid-Phase Extraction and...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) are biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs).
• Accurate determination of OH-PAHs in biological samples like urine is crucial for health risk assessment.
• Existing methods often face challenges with sensitivity, selectivity, and sample matrix interference.

Purpose of the Study:

• To develop and validate a solid-phase extraction (SPE) method for determining trace OH-PAHs in urine.
• To utilize a novel diatomite-supported graphene oxide composite (GO@Dt-NH2) as an SPE adsorbent.
• To couple the SPE method with high-performance liquid chromatography (HPLC) for sensitive analysis.

Main Methods:

• Fabrication and characterization of the graphene oxide-diatomite composite (GO@Dt-NH2) using X-ray powder diffractometry and scanning electron microscopy.
• Optimization of SPE parameters, including the amount of graphene oxide and extraction conditions.
• Analysis of target OH-PAHs (2-hydroxy-naphthalene, 2-hydroxy-fluorene, 1-hydroxy-phenanthrene, 1-hydroxy-pyrene) in urine samples using HPLC.

Main Results:

• The GO@Dt-NH2 composite demonstrated enhanced adsorption affinity for OH-PAHs compared to bare diatomite.
• The developed SPE-HPLC method exhibited good linearity (0.30-200 ng/mL) and low detection limits (0.10-0.15 ng/mL).
• High average recoveries (90.6%-100%) and acceptable relative standard deviations (intra-day: 1.8-6.4%, inter-day: 2.7-11.8%) were achieved.
• The adsorbent provided significant enrichment factors (18-20) and excellent purification capabilities.

Conclusions:

• The fabricated GO@Dt-NH2 composite is a highly effective adsorbent for SPE of trace OH-PAHs in urine.
• The developed SPE-HPLC method is sensitive, reliable, and suitable for the determination of OH-PAHs in real-world samples.
• The method was successfully applied to analyze OH-PAHs in urine from smoking volunteers, indicating its practical utility.