Ultrasmall HKUST-1 nanoparticles decorated graphite nanosheets for highly sensitive electrochemical sensing of DNA damage biomarker 8-hydroxy-2'-deoxyguanosine

Highlights: • HKUST-1 decorated graphite nanosheets (HKUST-1/GN) hybrids are easily in-situ prepared. • HKUST-1/GN hybrids show remarkably enhanced adsorption property. • High sensitivity and selectivity is achieved toward 8-hydroxy-2'-deoxyguanosine sensing. • The strategy provides guidance for the synthesis of other electrode materials. -- Abstract: Herein, graphite nanosheets (GN) were first prepared through simple liquid-phase exfoliation of graphite powder in N, N-dimethylacetamide (DMAC). After then, ultrasmall Cu-based metal organic frame (HKUST-1) nanoparticles (less than 5 nm) were in-situ anchored on the surface of graphite nanosheets with high degree of dispersion. Due to the intrinsic structural advantages of the as-synthesized HKUST-1 nanoparticles decorated graphite nanosheets (HKUST-1/GN) hybrids, including superior electron transfer ability and the greatly enhanced adsorption property, HKUST-1/GN shows excellent electrochemical sensing performance toward DNA damage biomarker 8-hydroxy-2'-deoxyguanosine with fast detection speed (∼240 s), wide linear window (10 nM–1 μM), high sensitivity (346857 μA mM⁻¹ cm⁻²), low detection limit (∼2.5 nM), and good reproducibility. As a result, a highly sensitive electrochemical sensing platform for the detection of DNA damage biomarker 8-hydroxy-2'-deoxyguanosine was fabricated basing the as-prepared HKUST-1/GN hybrids. What is more, the developed electrochemical method was successfully used for the detection of real samples and exhibited satisfied result.