Back to Search
Start Over
A label-free and sensitive electrochemical aptasensor for thrombin based on the direct electron transfer of hemin and hemin@rGO nanosheets as the signal probe
- Source :
- Analytical Methods. 7:8771-8777
- Publication Year :
- 2015
- Publisher :
- Royal Society of Chemistry (RSC), 2015.
-
Abstract
- In this work, a label-free electrochemical aptasensor for sensitive detection of thrombin was fabricated and characterized. This aptasensor was based on the direct electron transfer of hemin and hemin functionalized reduced graphene oxide hybrid nanosheets (hemin@rGO) as the signal probe. Hemin@rGO with intrinsic peroxidase-like activity could catalyze the reaction of the peroxidase substrate because of the catalytic ability of hemin attached on the graphene surface through π–π interactions. The greatly enhanced sensitivity of the as-prepared aptasensor for thrombin was based on an effective signal amplification strategy. Firstly, the synthesized hemin@rGO nanosheets not only provided a large conductive interface, but also exhibited excellent redox activity with avoidance of an extra electroactive mediator. Secondly, the electrodeposition of Pt nanoparticles (PtNPs) on the resultant electrode surface effectively promoted the electron transfer and amplified the electrochemical response. Thirdly, further enhanced sensitivity was achieved by the outstanding catalytic performance of the horseradish peroxidase as the blocking reagent. On the basis of such a signal amplification strategy, the direct and facile electrochemical aptasensor showed superior electrocatalytic efficiency toward H2O2, and sensitively responded to 0.45 pM thrombin with a linear calibration range from 1 pM to 50 nM. So, the proposed detecting platform for thrombin could be promising for clinical analysis and assays.
- Subjects :
- biology
Graphene
Chemistry
General Chemical Engineering
Inorganic chemistry
General Engineering
Substrate (chemistry)
Electrochemistry
Combinatorial chemistry
Horseradish peroxidase
Analytical Chemistry
law.invention
Electron transfer
chemistry.chemical_compound
law
Reagent
Electrode
biology.protein
Hemin
Subjects
Details
- ISSN :
- 17599679 and 17599660
- Volume :
- 7
- Database :
- OpenAIRE
- Journal :
- Analytical Methods
- Accession number :
- edsair.doi...........9988b4f44e480592543f4de94b0778ee