Preparation of titanium ion functionalized polydopamine coated ferroferric oxide core-shell magnetic particles for selective extraction of nucleotides from Cordyceps and Lentinus edodes

Abstract In this study, a titanium ion (Ti 4+ ) functionalized polydopamine coated ferroferric oxide (Fe 3 O 4 @PDA@Ti 4+ ) core-shell magnetic particle was prepared for the selective extraction of nucleotides. Firstly, different metal ions including Ti 4+ , Zr 4+ , Fe 3+ , Al 3+ , Cu 2+ , Zn 2+ , Ni 2+ and Mg 2+ were respectively immobilized onto Fe 3 O 4 @PDA particles and their extraction efficiency for five nucleotides [cytidine-5′-monophosphate (CMP), uridine-5′-monophosphate (UMP), guanosine-5′-monophosphate (GMP), thymidine-5′-monophosphate (TMP) and adenosine-5′-monophosphate (AMP)] were compared. Among these prepared materials, Fe 3 O 4 @PDA@Ti 4+ , which exhibited the highest extraction efficiency for nucleotides, was further characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. After being optimized of the extraction parameters including adsorbent amounts, extraction time, extraction temperature, type and concentration of the eluent, the prepared Fe 3 O 4 @PDA@Ti 4+ magnetic particles were successfully applied for the selective extraction and determination of CMP, UMP, GMP, TMP and AMP in Cordyceps and Lentinus edodes . Good linearity (varying from 0.063 to 19.000 μg/mL, R 2  > 0.999) and low limit of detection (LODs) (ranging between 0.0047 and 0.0141 μg/mL) for target analytes were achieved. These results demonstrated that the synthesized material in this study had potential for selective extraction of phosphorylated small molecular compounds in complicated matrix.