Name: development and functionalization of electrolyte-gated graphene field-effect transistor for biomarker detection
Uploaded: 2022-02-01T14:20:00
Description: Watch this Scientific Journal Video about Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection at JoVE.com

The experiments were conducted at West Virginia University. We acknowledge the Shared Research Facilities at West Virginia University for device fabrication and material characterization. This work was supported by the US National Science Foundation under Grant No. NSF1916894.

1. Transferring chemical vapor deposition of graphene
<ol>
	<li>Cut the graphene sheet on a copper substrate in half (2.5 cm x 5 cm) using scissors. Apply heat resistive tape to fix the four corners of the graphene square on a spinner gasket (see Table of Materials). 
	NOTE: The purchased graphene has a dimension of 5 cm x 5 cm (see Table of Materials).</li>
	<li>Spin-coat the sheet of the graphene with a thin layer (100-200 nm) of PMMA 495K A4 spinning at 500 rpm...

<ol>
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C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrinsic+response+of+graphene+vapor+sensors.">Intrinsic response of graphene vapor sensors.</a> Nano Letters. 9 (4), 1472-1475 (2009).</li><li>Zhang, A., Lieber, C. M. -. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nano-Bioelectronics.">Nano-Bioelectronics.</a> Chemical Reviews. 116 (1), 215-257 (2015).</li><li>Forsyth, R., Devadoss, A., Guy, O. 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The purchased CVD graphene on copper film needs to be trimmed to the right size for the following fabrication steps. Cutting of the films can cause wrinkling, which needs to be prevented. The parameters provided in the fabrication step can be referred to for plasma etching of graphene, and these numbers could be varied when using different instruments. The etched sample must be closely monitored and inspected to ensure complete graphene etching. Multiple pre-cleaning methods can be applied to clean the substrates, such a...

Graphene and its derivatives have been investigated and used for many applications, including electronics1,2, sensing3,4,5, energy storage6,7, and photocatalysis1,6,8. Synthesis and fabrication of high quality, good uniformity, and low defects graphene are critical for high-performance and highly sensitive devices. Since the development of Chemical vapor deposition (CVD) in 2009, it has shown colossal promise and set its place as an essential member of the graphene family9,10,11,12,13. It is grown on a metal substrate and, later for practical uses, is transferred onto insulating substrates14. Several transferring methods have been used to transfer CVD graphene recently. The poly (methyl methacrylate) (PMMA) assisted method is the most used among the different techniques. This method is particularly well-suited for industrial usage because of its large-scale capability, lower cost, and high quality of the transferred graphene14,15. The critical aspect of this method is getting rid of the PMMA residue for CVD graphene&#39;s applications because the residues can cause declination of the electronic properties of graphene14,15,16, cause an effect on biosensors&#39; sensitivity and performance17,18, and create significant device-to-device variations19.
Nanomaterials-based biosensors have been significantly investigated over the past decades, including silicon nanowire (SiNW), carbon nanotube (CNT), and graphene20. Because of its single-atom-layer structure and distinctive properties, graphene demonstrates superior electronic characteristics, good biocompatibility, and facile functionalization, making it an attractive material for developing biosensors14,21,22,23. Due to field-effect transistors (FET) characteristics such as high sensitivity, standard configuration, and cost-effective mass producibility21,24, FET is more preferred in portable and point-of-care implementations than other electronics-based biosensing devices. The electrolyte-gated graphene field-effect transistor (EGGFET) biosensors are examples of the stated FETs21,24. EGGFET can detect various targeting analytes such as nucleic acids25, proteins24,26, metabolites27, and other biologically relevant analytes28. The technique mentioned here ensures the implementation of CVD graphene in a label-free biosensing nanoelectronics device which offers higher sensitivity and accurate time detection over other biosensing devices29.
In this work, an overall process for developing an EGGFET biosensor and functionalizing it for biomarker detection, including transferring CVD graphene onto an insulating substrate, Raman, and AFM characterizations of the transferred graphene, are demonstrated. Furthermore, fabrication of EGGFET and integration with a polydimethylsiloxane (PDMS) sample delivery well, bioreceptor functionalization, and successful detection of human immunoglobulin G (IgG) from serum by spike-and-recovery experiments are also discussed here.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1-pyreneutyric acid N- hydroxysuccinimide ester</td>
			<td>Sigma Aldrich</td>
			<td>457078-1G</td>
			<td>functionalization</td>
		</tr>
		<tr>
			<td>Asylum MFP-3D Atomic Force Microscope</td>
			<td>Oxford Instruments</td>
			<td></td>
			<td>graphene characterization</td>
		</tr>
		<tr>
			<td>AZ 300 MIF</td>
			<td>MicroChemicals</td>
			<td>AZ 300 MIF</td>
			<td>photoresist developer</td>
		</tr>
		<tr>
			<td>AZ 300 MIF</td>
			<td>MicroChemicals</td>
			<td>AZ 300 MIF</td>
			<td>photoresist</td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>Sigma Aldrich</td>
			<td>810014</td>
			<td>blocking</td>
		</tr>
		<tr>
			<td>Branson 1210 Sonicator</td>
			<td>SONITEK</td>
			<td></td>
			<td>sample cleaning</td>
		</tr>
		<tr>
			<td>Copper Etchant</td>
			<td>Sigma Aldrich</td>
			<td>667528-500ML</td>
			<td>removing copper film to release graphene</td>
		</tr>
		<tr>
			<td>Dimethyl Sulfoxide (DMSO)</td>
			<td>VWR</td>
			<td>97063-136</td>
			<td>functionalization</td>
		</tr>
		<tr>
			<td>Disposable Biopsy Punches, Integra Miltex</td>
			<td>VWR</td>
			<td>21909-144</td>
			<td>create well in PDMS</td>
		</tr>
		<tr>
			<td>Gold etchant</td>
			<td>Gold Etch, TFA, Transene</td>
			<td>658148</td>
			<td>enchant</td>
		</tr>
		<tr>
			<td>Graphene</td>
			<td>Graphene supermarket</td>
			<td>2&#34; x 2&#34; sheet</td>
			<td>biosensing element of the device</td>
		</tr>
		<tr>
			<td>IgG aptamer</td>
			<td>Base Pair Biotechnologies</td>
			<td>customized</td>
			<td>bioreceptor</td>
		</tr>
		<tr>
			<td>Keithley 4200A-SCS Parameter Analyzer</td>
			<td>Tektronix</td>
			<td></td>
			<td>measurement and detection</td>
		</tr>
		<tr>
			<td>KMG CR-6</td>
			<td>KMG chemicals</td>
			<td>64216</td>
			<td>Chromium etchant</td>
		</tr>
		<tr>
			<td>Kurt J. Lesker E-beam Evaporator</td>
			<td>Kurt J. Lesker</td>
			<td></td>
			<td>metal deposition</td>
		</tr>
		<tr>
			<td>Laurell Technologies 400 Spinners</td>
			<td>Laurell Technologies</td>
			<td>WS-400BZ-6NPP/LITE</td>
			<td>thin film coating</td>
		</tr>
		<tr>
			<td>March PX-250 Plasma Asher</td>
			<td>March Instruments</td>
			<td></td>
			<td>sample cleaning</td>
		</tr>
		<tr>
			<td>Nickel etchant</td>
			<td>Nickel Etchant, TFB, Transene</td>
			<td>600016000</td>
			<td>etchant</td>
		</tr>
		<tr>
			<td>OAI Flood Exposure</td>
			<td>OAI</td>
			<td></td>
			<td>photolithography</td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline (PBS)</td>
			<td>Sigma Aldrich</td>
			<td>806552-500ML</td>
			<td>buffer</td>
		</tr>
		<tr>
			<td>PMMA 495K A4</td>
			<td>MicroChemicals</td>
			<td>PMMA 495K A4</td>
			<td>Photoresist for assisting graphene transferring</td>
		</tr>
		<tr>
			<td>Polydimethylsiloxane (PDMS)</td>
			<td>Sigma Aldrich</td>
			<td>Sylgard 184</td>
			<td>sample delivery well</td>
		</tr>
		<tr>
			<td>Renishaw InVia Raman Microscope</td>
			<td>Renishaw</td>
			<td></td>
			<td>graphene characterization</td>
		</tr>
		<tr>
			<td>Sodium Hydroxide (NaOH)</td>
			<td>Sigma Aldrich</td>
			<td>221465-25G</td>
			<td>functionalization</td>
		</tr>
		<tr>
			<td>Suss Microtech MA6 Mask Aligner</td>
			<td>Suss MicroTec</td>
			<td></td>
			<td>photolithography</td>
		</tr>
		<tr>
			<td>Thermo Scientific Cimarec Hotplate</td>
			<td>Thermo Scientific</td>
			<td>SP131635</td>
			<td>sample and device Baking</td>
		</tr>
	</tbody>
</table>

development and functionalization of electrolyte-gated graphene field-effect transistor for biomarker detection

In the current study, graphene and its derivatives have been investigated and used for many applications, including electronics, sensing, energy storage, and photocatalysis. Synthesis and fabrication of high quality, good uniformity, and low defects graphene are critical for high-performance and highly sensitive devices. Among many synthesis methods, chemical vapor deposition (CVD), considered a leading approach to manufacture graphene, can control the number of graphene layers and yield high-quality graphene. CVD graphene needs to be transferred from the metal substrates on which it is grown onto&#160;insulating substrates for practical applications. However, separation and transferring of graphene onto new substrates are challenging for a uniform layer without damaging or affecting graphene&#39;s structures and properties. Additionally, electrolyte-gated graphene field-effect transistor (EGGFET) has been demonstrated for its wide applications in various biomolecular detections because of its high sensitivity and standard device configuration. In this article, poly (methyl methacrylate) (PMMA)-assisted graphene transferring approach, fabrication of graphene field-effect transistor (GFET), and biomarker immunoglobulin G (IgG) detection are demonstrated. Raman spectroscopy and atomic force microscopy were applied to characterize the transferred graphene. The method is shown to be a practical approach for transferring clean and residue-free graphene while preserving the underlying graphene lattice onto an insulating substrate for electronics or biosensing applications.

The representative results show the transferred CVD graphene characterized by Raman and AFM, respectively. The G peak and the 2D peaks of the Raman image give comprehensive information regarding the existence and the quality of the transferred monolayer graphene32 (Figure 1). Standard lithography processes30,31 were applied for fabricating the GFET device, as shown in Figure 2. <s...

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Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection

The present protocol demonstrates the development of electrolyte-gated graphene field-effect transistor (EGGFET) biosensor and its application in biomarker immunoglobulin G (IgG) detection.

In the current study, graphene and its derivatives have been investigated and used for many applications, including electronics, sensing, energy storage, ...

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Engineering

Synthesis and Functionalization of Nitrogen-doped Carbon Nanotube Cups with Gold Nanoparticles as Cork Stoppers

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Development of a 3D Graphene Electrode Dielectrophoretic Device

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Owing to its relativistic low-energy charge carriers, the interaction between graphene and various impurities leads to a wealth of new physics and degrees ...

Visible-light Induced Reduction of Graphene Oxide Using Plasmonic Nanoparticle

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Synthesis and Functionalization of 3D Nano-graphene Materials: Graphene Aerogels and Graphene Macro Assemblies

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Effect of Bending on the Electrical Characteristics of Flexible Organic Single Crystal-based Field-effect Transistors

The charge transport in an organic semiconductor depends highly on the molecular packing in the crystal, which influences the electronic coupling ...

Atmospheric Pressure Fabrication of Large-Sized Single-Layer Rectangular SnSe Flakes

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Guidelines and Experience Using Imaging Biomarker Explorer (IBEX) for Radiomics

Guidelines and Experience Using Imaging Biomarker Explorer IBEX for Radiomics

Imaging Biomarker Explorer (IBEX) is an open-source tool for medical imaging radiomics work. The purpose of this paper is to describe how to use IBEX's ...

Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding

Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding

The assembly of two-dimensional (2D) graphene into three-dimensional (3D) polyhedral structures while preserving the graphene's excellent inherent ...

Preparation of Graphene Liquid Cells for the Observation of Lithium-ion Battery Material

In this work, we introduce the preparation of graphene liquid cells (GLCs), encapsulating both electrode materials and organic liquid electrolytes between ...