Biosensors for detecting biomarkers and methods of fabricating and using the same

Patent metadata

Field	Value
Publication number	US-12130286-B2
Application number	US-202217806109-A
Country	US
Kind code	B2
Filing date	Jun 9, 2022
Priority date	Jun 9, 2022
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

Biosensors capable of detecting certain biomarkers (e.g., platelet-derived growth factor-BB (PDGF-BB)), as well as methods of fabricating the same and methods of using the same, are provided. The biosensors can be disposable and/or label-free. Electrochemical bipolar exfoliation can be used to exfoliate, reduce, and deposit (in a single step) graphene nanosheets on a desired substrate (e.g., an electrode). Affinity aptamers can be immobilized on the graphene nanosheets disposed on the substrate.

First claim

What is claimed is:

1. A biosensor for detecting a biomarker, the biosensor comprising:
an electrode comprising a metal;
reduced graphene oxide (rGO) disposed on the electrode, the rGO comprising graphene nanosheets; and
a plurality of aptamers disposed on the rGO, the plurality of aptamers being configured to bind to the biomarker,
the plurality of aptamers being directly immobilized on the graphene nanosheets without any mediator or linking layer disposed therebetween,
the rGO covering at least 90% of an upper surface of the metal of the electrode, and
the rGO having a vertically aligned structure.

2. The biosensor according to claim 1 , the electrode further comprising a substrate on which the metal is disposed.

3. The biosensor according to claim 2 , the substrate being a polymer.

4. The biosensor according to claim 3 , the substrate being polyethylene terephthalate (PET).

5. The biosensor according to claim 1 , the metal being gold (Au).

6. The biosensor according to claim 1 , the metal being stainless steel (SS).

7. The biosensor according to claim 1 , the biomarker being a cancer biomarker.

8. The biosensor according to claim 1 , the biomarker being platelet-derived growth factor-BB (PDGF-BB).

9. The biosensor according to claim 1 , the biosensor being label-free.

10. The biosensor according to claim 1 , the biosensor being disposable.

11. The biosensor according to claim 1 , the biosensor having a lower limit of detection for the biomarker of less than 1 picomolar (pM).

12. A biosensor for detecting a biomarker, the biosensor comprising:
an electrode comprising a metal;
reduced graphene oxide (rGO) disposed on the electrode, the rGO comprising graphene nanosheets; and
a plurality of aptamers disposed on the rGO, the plurality of aptamers being configured to bind to the biomarker,
the biomarker being platelet-derived growth factor-BB (PDGF-BB),
the rGO covering at least 90% of an upper surface of the metal of the electrode,
the rGO having a vertically aligned structure,
the biosensor being label-free,
the biosensor being disposable,
the biosensor having a lower limit of detection for the biomarker of less than 1 picomolar (pM),
the plurality of aptamers being directly immobilized on the graphene nanosheets without any mediator or linking layer disposed therebetween, and
the electrode comprising either feature a) or feature b):
a) the electrode comprising a substrate on which the metal is disposed, the metal being gold (Au), and the substrate being polyethylene terephthalate (PET); or
b) the metal of the electrode being stainless steel (SS).

Assignees

• Forouzanfar Shahrzad
• Khakpour Iman
• Pala Nezih
• Wang Chunlei
• The Florida International Univ Board Of Trustees

Inventors

• Forouzanfar Shahrzad
• Khakpour Iman
• Pala Nezih
• Wang Chunlei

Classifications

• G01N33/5758 Primary

  involving compounds serving as markers for tumours, cancers or neoplasias, e.g. cellular determinants, receptors, heat shock/stress proteins, A-protein, oligosaccharides or metabolites · CPC title

• G01N2333/49

  Platelet-derived growth factor [PDGF] · CPC title

• G01N27/3276

  being a hybridisation with immobilised receptors (using a FET type sensor G01N27/4145; concerning the hybridisation C12Q1/68) · CPC title

• G01N27/308

  at least partially made of carbon · CPC title

• G01N33/5438 Primary

  Electrodes · CPC title