Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 42
·14723-14731
·
IF 7.059
Lele Li,Liwei Yang,Si Zhang,Yuping Sun,Fen Li,Tengteng Qin,Xiaoqiang Liu,Yanmei Zhou,Subbiah Alwarappan
Herein, we designed a NiCo2S4@N/S–CeO2 composite with amplified electrocatalytic oxygen reduction (OR) capability by the in situ growth of NiCo2S4 nanoparticles on CeO2 nanospheres with simultaneous doping of nitrogen and sulfur. After optical characterization of the composite, it was then employed as the signal amplification label for constructing an electrochemical aptasensor. The composite provides a biocompatible and large surface platform to load biomolecules and retain their bioactivity. More importantly, the composite shows a comparable electrocatalytic OR capability similar to a commercial Pt/C catalyst and far better than CeO2, attributed to the NiCo2S4 deposition and oxygen vacancies introduced by N and S doping. Furthermore, the Koutecky–Levich plots indicate a nearly four-electron transfer pathway of the ORR. The as-prepared aptasensor exhibited a highly sensitive and selective determination of a model analyte-sulfadimethoxine with a wide linear range of 0.05–180 nM, a low detection limit of 0.02 ± 0.0011 nM and good feasibility for real-sample detection. This work paved an effective way for the design of highly efficient electrocatalysts with bright prospects in bioanalytical applications.
研究领域:
电化学
·
生物传感器
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 32
·20838-20849
·
IF 4.036
Hanzhang Ye,Yongli Ding,Tingting Liu,Jiani Li,Qi Wang,Yuhao Li,Jingjing Gu,Zhanen Zhang,Xuedong Wang
Traditional bimetallic sulfide-based nanomaterials often have a small specific surface area (SSA), low dispersion, and poor conductivity, thereby limiting their wide applications in the nanozyme-catalytic field. To address the above issues, we herein integrated NiCo2S4 with N,S-rGO to fabricate a nanocomposite (NiCo2S4@N,S-rGO), which showed a stronger peroxidase–mimetic activity than its pristine components. The SSA (155.8 m2 g−1) of NiCo2S4@N,S-rGO increased by ∼2-fold compared to NiCo2S4 with a pore size of 7–9 nm, thus providing more active sites and charge transfer channels. Based on the Michaelis–Menten equation, the affinity of this nanocomposite increased 40% and 1.1∼10.6-fold compared with NiCo2S4 with N,S-rGO, respectively, highlighting the significant enhancement of the peroxidase-like activity. The enhanced activity of this nanocomposite is derived from the joint participation of ˙OH, ˙O2−, and photogenerated holes (h+), and was dominated by h+. To sum up, N,S-codoping, rich S-vacancies, and multi-valence states for this nanocomposite facilitate electron transfer and accelerate reaction processes. The nanocomposite-based colorimetric sensor gave low detection limits for H2O2 (12 μM) and glucose (0.3 μM). In comparison with the results detected by a common glucose meter, this sensor provided the relative recoveries across the range of 97.4–101.8%, demonstrating its high accuracy. Moreover, it exhibited excellent selectivity for glucose assay with little interference from common co-existing macromolecules/ions, as well as high reusability (>6 times). Collectively, the newly developed colorimetric sensor yields a promising methodology for practical applications in H2O2 and glucose detection with advantages of highly visual resolution, simple operation, convenient use, and satisfactory sensitivity.
研究领域:
生物化学
·
分析化学
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）