Amorphous ZrO₂-Modified Polymeric Microspheres for Effective Separation of Nucleoside Analogues

Due to the diverse roles of nucleoside analogues in biological processes, their coexistence often complicates drug therapeutic effect and disease diagnosis, then effective separation of nucleoside analogues becomes extremely important. However, the separation of nucleoside analogues remains challenging. Herein, we combined the metal oxide affinity technology with solid-phase extraction by depositing ZrO₂-nanoparticles on the PS@PAA microspheres to form a type of functional composite, and the selective adsorption of adenosine (Ado), adenosine-5'-monophosphate (AMP) and deoxyadenosine (dA) was achieved by exploiting their differential interactions with the hybrid microspheres, reaching selectivity coefficients of α_(AMP/Ado) = 23.73 and α_(Ado/dA) = 10.14 under optimized conditions. Mechanism investigation shows that this selectivity is mainly caused by the coordination of Zr(IV) with diol and phosphate groups in Ado, AMP and dA. Meanwhile, the hydrogen bonding is also an important parameter for the selectivity coefficients of the nucleoside analogues. Based on these, a versatile adsorption-elution protocol was established and successfully applied to the effective separation of adenosine analogues from mixed samples. This work thus provides a facile and effective strategy for the separation of structural analogues.