Chitosan-based metal organic coordination polymers/silica hybrid monoliths for use in urinary...

8-Hydroxy-2'-deoxyguanosine (8-OHdG) has been widely applied as a biomarker in oxidative DNA damage-related diseases. In this study, a new analysis for urinary 8-OHdG levels is proposed as a potential analytical approach for urinary 8-OHdG determination. Applying a facile one-step self-assembly procedure, zinc(II)-chitosan coordination polymer/silica (ZCCPS) and copper(II)-chitosan coordination polymer/silica (CCCPS) hybrid monoliths have been prepared. The presence of 8-OHdG in human urine was quantitatively determined using solid-phase micro-extraction (SPME) coupled with high-performance liquid chromatography and ultraviolet (HPLC-UV) analysis. Tests have established 8-OhdG extraction factors (EFs) of 61.64 and 51.20 for CCCPS and ZCCPS, respectively, demonstrating that the chitosan-based metal organic coordination polymer/silica hybrid monoliths deliver superior extraction efficiency. Analyses based on CCCPS and ZCCPS hybrid monoliths are linear (R² > 0.99) in the 1.9-100 and 8.8-100 nmol L^-1 ranges, respectively. Moreover, the associated limits of detection (LODs) are 0.58 nmol L^-1 and 2.70 nmol L^-1 (N/S = 3) with respective spiking recoveries from 90.20% to 104.56% and 91.40% to 106.68% (n = 3), indicating a high level of accuracy. In addition, the respective relative standard deviations (RSDs) for intra-day and inter-day precision are in the 3.65-4.72% and 4.83-5.79% ranges. Testing has confirmed that the SPME-HPLC-UV analyses deliver sensitive, reliable, and accurate detection of 8-OHdG in urine samples.