A highly sensitive sensor inspired by the papillary structure of cactus for simultaneous detection of glucose and H₂O₂

Designing an electrochemical sensor with high sensitivity and the ability to simultaneously detect multiple biomarkers is a challenging and significant research. Inspired by the water collection function of cactus papillary structures, a high-performance sensor (MCeO₂@γFe₂O₃ sensor) featuring a sponge-like nanoporous architecture and a bionic papillary array was constructed based on the CeO₂@γFe₂O₃ composite structure with lattice shap. The composite structure has transition metal carbide (MXene) as the framework and CeO₂@γFe₂O₃ composite nanoparticles as attachments. The sensor exhibits enhanced redox reaction activity, which is attributed to the combination of its unique microstructure and the substantial increase in oxygen vacancy concentration within the crystal lattice following recombination. This contributes to its superior detection performance in comparison to conventional electrochemical detection sensors. Its sensitivity is 11.0 mA mM⁻¹ cm⁻² (glucose detection) and 1.10 mA μM⁻¹ cm⁻² (H₂O₂ detection). It features the low limit of detection (glucose: 0.25 μM, H₂O₂: 0.010 nM) and the ultra-wide linear detection range (glucose: 1.0 mM–40.0 mM, H₂O₂: 0.10 nM-1.0 × 10² μM), which can meet the needs of blood glucose and H₂O₂ level detection. In addition, the sensor is capable of simultaneously detecting glucose and H₂O₂, demonstrating excellent selectivity, consistency, durability (300 cycles) and the potential to achieve accurate detection in the human blood environment. This study proposes a novel strategy for the development of an integrated high-performance sensor that enables simultaneous multi-biomarker detection, opening new avenues for innovation in blood testing technology.