Ping Li1, Wenchao Zhang1, Xuan Zhou1, Lun Zhang2. 1. Department of Maxillofacial & E.N.T. Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin 300020, PR China. 2. Department of Maxillofacial & E.N.T. Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin 300020, PR China. Electronic address: zhanglun@tjmuch.com.
Abstract
BACKGROUND AND OBJECTIVES: Electrochemical immunosensors have attracted much interest recently. Some researches on electrochemical PCT measurement have been reported but improvements are still needed to enhance detection performance for the clinical determination of PCT. DESIGN AND METHODS: In this work, a novel signal amplification strategy was developed by fabricating an electrochemical immunosensor for the sensitive detection of procalcitonin (PCT). Amino group-functionalised C(60) nanoparticles were used as a matrix to immobilise a redox probe, ferrocene carboxylic acid (Fc), and were subsequently coated with platinum nanoparticles (PtNPs) to form PtNP-Fc-C(60) nanocomposites. RESULTS: The experimental results demonstrated that the multi-labelled PtNP-Fc-C(60) nanocomposites displayed satisfactory electrochemical redox activity and high electrocatalytic activity from the PtNPs and glucose oxidase, consequently resulting in high sensitivity for the detection of PCT. The linear range of PCT was 0.01-10 ng/mL, with a detection limit of 6p g/mL (S/N = 3). CONCLUSION: Although the proposed immunosensor was only to determine PCT in this study, we expect that this immunosensor should be suitable for the determination of other targets in similar signal-enhanced immunoassays.
BACKGROUND AND OBJECTIVES: Electrochemical immunosensors have attracted much interest recently. Some researches on electrochemical PCT measurement have been reported but improvements are still needed to enhance detection performance for the clinical determination of PCT. DESIGN AND METHODS: In this work, a novel signal amplification strategy was developed by fabricating an electrochemical immunosensor for the sensitive detection of procalcitonin (PCT). Amino group-functionalised C(60) nanoparticles were used as a matrix to immobilise a redox probe, ferrocene carboxylic acid (Fc), and were subsequently coated with platinum nanoparticles (PtNPs) to form PtNP-Fc-C(60) nanocomposites. RESULTS: The experimental results demonstrated that the multi-labelled PtNP-Fc-C(60) nanocomposites displayed satisfactory electrochemical redox activity and high electrocatalytic activity from the PtNPs and glucose oxidase, consequently resulting in high sensitivity for the detection of PCT. The linear range of PCT was 0.01-10 ng/mL, with a detection limit of 6p g/mL (S/N = 3). CONCLUSION: Although the proposed immunosensor was only to determine PCT in this study, we expect that this immunosensor should be suitable for the determination of other targets in similar signal-enhanced immunoassays.