Abstract
Procalcitonin (PCT) is an inflammatory marker with significance in the early diagnosis of sepsis. The label-free electrochemical impedance immunosensor has good prospects for the determination of this disease marker due to its cost-effectiveness, high specificity and simple operation. However, developing an immunosensor for procalcitonin faces challenges due to the absence of satisfactory electrodes. Herein, a novel label-free electrochemical impedance immunosensor using the three-dimensional (3D) flower-shaped gold nanoparticle@molybdenum(IV) sulfide/graphene (Au NPs@MoS2/graphene) composite is reported for procalcitonin. Under the optimal conditions, the immunosensor presents a linear response from 10 fg mL−1 to 50 ng mL−1 and an ultra-low detection limit of 2.3 fg mL−1 for for procalcitonin. The excellent performance is due to the unique 3D flower-shape and the synergistic effect of Au NPs@MoS2/graphene, generating a large surface area, high electrical conductivity, and increased immobilization of anti-PCT. Additionally, the immunosensor exhibits suitable specificity, stability, and reproducibility, and was used to determine procalcitonin in serum which may allow clinical screening and diagnosis of sepsis.
Acknowledgments
The authors would like to thank Wei Xiao and Lili Zou for their help with the ethical review.
Disclosure statement
The authors report there are no competing interests to declare.