Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-30T10:53:57.177Z Has data issue: false hasContentIssue false

Challenges in fabricating graphene nanodevices for electronic DNA sequencing

Published online by Cambridge University Press:  06 September 2018

Jasper P. Fried
Affiliation:
Department of Materials, University of Oxford, Oxford OX1 3PH, UK
Jacob L. Swett
Affiliation:
Department of Materials, University of Oxford, Oxford OX1 3PH, UK
Xinya Bian
Affiliation:
Department of Materials, University of Oxford, Oxford OX1 3PH, UK
Jan A. Mol*
Affiliation:
Department of Materials, University of Oxford, Oxford OX1 3PH, UK
*
Address all correspondence to Jan A. Mol at jan.mol@materials.ox.ac.uk
Get access

Abstract

Graphene-based electronic DNA sequencing techniques have received significant attention over the past decade and are hoped to provide a new generation of portable, low-cost devices capable of rapid and accurate DNA sequencing. However, these devices are yet to demonstrate DNA sequencing. This is partly due to complex fabrication requirements resulting in low device yields and limited throughput. In this paper, we review the challenging fabrication of graphene-based electronic DNA sequencing devices. We will place a particular focus on common fabrication challenges and look toward the development of high-throughput, high-yield fabrication of these devices.

Type
2D Nanomaterials for Healthcare and Lab-on-a-Chip Devices Prospective Articles
Copyright
Copyright © Materials Research Society 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Shendure, J. and Ji, H.: Next-generation DNA sequencing. Nat. Biotechnol. 26, 11351145 (2008).Google Scholar
2.Metzker, M.L.: Sequencing technologies—the next generation. Nat. Rev. Genet. 11, 3146 (2009).Google Scholar
3.Deamer, D., Akeson, M., and Branton, D.: Three decades of nanopore sequencing. Nat. Biotechnol. 34, 518524 (2016).Google Scholar
4.Schadt, E.E., Turner, S., and Kasarskis, A.: A window into third-generation sequencing. Hum. Mol. Genet. 19, R227R240 (2010).Google Scholar
5.Norris, A.L., Workman, R.E., Fan, Y., Eshleman, J.R., and Timp, W.: Nanopore sequencing detects structural variants in cancer. Cancer Biol. Ther. 17, 246253 (2016).Google Scholar
6.Stankiewicz, P. and Lupski, J.R.: Structural variation in the human genome and its role in disease. Annu. Rev. Med. 61, 437455 (2010).Google Scholar
7.Mardis, E.R.: Next-generation DNA sequencing methods. Annu. Rev. Genom. Hum. Genet. 9, 387402 (2008).Google Scholar
8.Chaisson, M.J.P., Wilson, R.K., and Eichler, E.E.: Genetic variation and the de novo assembly of human genomes. Nat. Rev. Genet. 16, 627640 (2015).Google Scholar
9.Branton, D., Deamer, D.W., Marziali, A., Bayley, H., Benner, S.A., Butler, T., Di Ventra, M., Garaj, S., Hibbs, A., Huang, X., Jovanovich, S.B., Krstic, P.S., Lindsay, S., Ling, X.S., Mastrangelo, C.H., Meller, A., Oliver, J.S., Pershin, Y.V., Ramsey, J.M., Riehn, R., Soni, G.V., Tabard-Cossa, V., Wanunu, M., Wiggin, M., and Schloss, J.A.: The potential and challenges of nanopore sequencing. Nat. Biotechnol. 26, 11461153 (2008).Google Scholar
10.Dekker, C.: Solid-state nanopores. Nat. Nanotechnol. 2, 209215 (2007).Google Scholar
11.Wang, Y., Yang, Q., and Wang, Z.: The evolution of nanopore sequencing. Front. Genet. 5, (2015). Article no. 449.Google Scholar
12.Kasianowicz, J.J., Brandin, E., Branton, D., and Deamer, D.W.: Characterization of individual polynucleotide molecules using a membrane channel. Proc. Natl. Acad. Sci. USA 93, 1377013773 (1996).Google Scholar
13.Cherf, G.M., Lieberman, K.R., Rashid, H., Lam, C.E., Karplus, K., and Akeson, M.: Automated forward and reverse ratcheting of DNA in a nanopore at 5a precision. Nat. Biotechnol. 30, 344348 (2012).Google Scholar
14.Manrao, E.A., Derrington, I.M., Laszlo, A.H., Langford, K.W., Hopper, M.K., Gillgren, N., Pavlenok, M., Niederweis, M., and Gundlach, J.H.: Reading DNA at single-nucleotide resolution with a mutant MspA nanopore and phi29 DNA polymerase. Nat. Biotechnol. 30, 349353 (2012).Google Scholar
15.Venkatesan, B.M. and Bashir, R.: Nanopore sensors for nucleic acid analysis. Nat. Nanotechnol. 6, 615624 (2011).Google Scholar
16.Mikheyev, A.S. and Tin, M.M.Y.: A first look at the oxford nanopore MinION sequencer. Mol. Ecol. Resour. 14, 10971102 (2014).Google Scholar
17.Jain, M., Olsen, H.E., Paten, B., and Akeson, M.: The oxford nanopore MinION: delivery of nanopore sequencing to the genomics community. Genome Biol. 17, (2016). Article no. 239.Google Scholar
18.Jain, M., Koren, S., Miga, K.H., Quick, J., Rand, A.C., Sasani, T.A., Tyson, J.R., Beggs, A.D., Dilthey, A.T., Fiddes, I.T., Malla, S., Marriott, H, Nieto, T., Grady, J.O., Olsen, H.E., Pedersen, B.S., Rhie, A., Richardson, H., Quinlan, A.R., Snutch, T.P., Tee, L., Paten, B., Phillippy, A.M., Simpson, J.T., Loman, N.J., and Loose, M.: Nanopore sequencing and assembly of a human genome with ultra-long reads. Nat. Biotechnol. 36, 338345 (2018).Google Scholar
19.Heerema, S.J. and Dekker, C.: Graphene nanodevices for DNA sequencing. Nat. Nanotechnol. 11, 127136 (2016).Google Scholar
20.Merchant, C.A., Healy, K., Wanunu, M., Ray, V., Peterman, N., Bartel, J., Fischbein, M.D., Venta, K., Luo, Z., Johnson, A.T.C., and Drndic, M.: DNA translocation through graphene nanopores. Nano Lett. 10, 29152921 (2010).Google Scholar
21.Schneider, G.F., Kowalczyk, S.W., Calado, V.E., Pandraud, G., Zandbergen, H.W., Vandersypen, L.M.K., and Dekker, C.: DNA translocation through graphene nanopores. Nano Lett. 10, 31633167 (2010).Google Scholar
22.Garaj, S., Hubbard, W., Reina, A., Kong, J., Branton, D., and Golovchenko, J.A.: Graphene as a subnanometre trans-electrode membrane. Nature 467, 190193 (2010).Google Scholar
23.Rosenstein, J.K., Wanunu, M., Merchant, C.A., Drndic, M., and Shepard, K.L.: Integrated nanopore sensing platform with sub-microsecond temporal resolution. Nat. Methods, 9, 487492 (2012).Google Scholar
24.Nelson, T., Zhang, B., and Prezhdo, O.V.: Detection of nucleic acids with graphene nanopores: Ab initio characterization of a novel sequencing device. Nano Lett. 10, 32373242 (2010).Google Scholar
25.Traversi, F., Raillon, C., Benameur, S.M., Liu, K., Khlybov, S., Tosun, M., Krasnozhon, D., Kis, A., and Radenovic, A.: Detecting the translocation of DNA through a nanopore using graphene nanoribbons. Nat. Nanotechnol. 8, 939945 (2013).Google Scholar
26.Postma, H.W.C.: Rapid sequencing of individual DNA molecules in graphene nanogaps. Nano Lett. 10, 420425 (2010).Google Scholar
27.Min, S.K., Kim, W.Y., Cho, Y., and Kim, K.S.: Fast DNA sequencing with a graphene-based nanochannel device. Nat. Nanotechnol. 6, 162165 (2011).Google Scholar
28.Healy, K., Ray, V., Willis, L.J., Peterman, N., Bartel, J., and Drndić, M.: Fabrication and characterization of nanopores with insulated transverse nanoelectrodes for DNA sensing in salt solution. Electrophoresis 33, 34883496 (2012).Google Scholar
29.Fanget, A., Traversi, F., Khlybov, S., Granjon, P., Magrez, A., Forró, L., and Radenovic, A.: Nanopore integrated nanogaps for DNA detection. Nano Lett. 14, 244249 (2013).Google Scholar
30.Heerema, S.J., Vicarelli, L., Pud, S., Schouten, R.N., Zandbergen, H.W., and Dekker, C.: Probing DNA translocations with inplane current signals in a graphene nanoribbon with a nanopore. ACS Nano 12, 23232633 (2018).Google Scholar
31.Yuan, Z., Wang, C., Yi, X., Ni, Z., Chen, Y., and Li, T.: Solid-state nanopore. Nanoscale Res. Lett. 13, (2018). Article no. 56.Google Scholar
32.Kim, H.S. and Kim, Y.-H.: Recent progress in atomistic simulation of electrical current DNA sequencing. Biosens. Bioelectron. 69, 186198 (2015).Google Scholar
33.Saha, K.K., Drndić, M., and Nikolić, B.K.: DNA base-specific modulation of microampere transverse edge currents through a metallic graphene nanoribbon with a nanopore. Nano Lett. 12, 5055 (2011).Google Scholar
34.Ouyang, F.-P., Peng, S.-L., Zhang, H., Weng, L.-B., and Xu, H.: A biosensor based on graphene nanoribbon with nanopores: a first-principles devices-design. Chin. Phys. B. 20, 058504 (2011).Google Scholar
35.Avdoshenko, S.M., Nozaki, D., da Rocha, C.G., González, J.W., Lee, M.H., Gutierrez, R., and Cuniberti, G.: Dynamic and electronic transport properties of DNA translocation through graphene nanopores. Nano Lett. 13, 19691976 (2013).Google Scholar
36.Girdhar, A., Sathe, C., Schulten, K., and Leburton, J.-P.: Graphene quantum point contact transistor for DNA sensing. Proc. Natl. Acad. Sci. USA 110, 1674816753 (2013).Google Scholar
37.Puster, M., Balan, A., Rodrguez-Manzo, J.A., Danda, G., Ahn, J.-H., Parkin, W., and Drndić, M.: Cross-talk between ionic and nanoribbon current signals in graphene nanoribbon-nanopore sensors for single-molecule detection. Small 11, 63096316 (2015).Google Scholar
38.Puster, M., Rodrguez-Manzo, J.A., Balan, A., and Drndić, M.: Toward sensitive graphene nanoribbon–nanopore devices by preventing electron beam-induced damage. ACS Nano 7, 1128311289 (2013).Google Scholar
39.Grant, A.W., Hu, Q.-H., and Kasemo, B.: Transmission electron microscopy windows for nanofabricated structures. Nanotechnology 15, 11751181 (2004).Google Scholar
40.Lee, M.-H., Kumar, A., Park, K.-B., Cho, S.-Y., Kim, H.-M., Lim, M.-C., Kim, Y.-R., and Kim, K.-B.: A low-noise solid-state nanopore platform based on a highly insulating substrate. Sci. Rep., 4, (2014). Article no. 7448.Google Scholar
41.Yanagi, I., Ishida, T., Fujisaki, K., and Takeda, K.i: Fabrication of 3-nm-thick si3n4 membranes for solid-state nanopores using the poly-si sacrificial layer process. Sci. Rep., 5, (2015). Article no. 14656.Google Scholar
42.Ivanov, A.P., Instuli, E., McGilvery, C.M., Baldwin, G., McComb, D.W., Albrecht, T., and Edel, J.B.: DNA tunneling detector embedded in a nanopore. Nano Lett. 11, 279285 (2011).Google Scholar
43.Temiz, Y., Ferretti, A., Leblebici, Y., and Guiducci, C.: A comparative study on fabrication techniques for on-chip microelectrodes. Lab. Chip. 12, 49204928 (2012).Google Scholar
44.Verschueren, D.V., Yang, W., and Dekker, C.: Lithography-based fabrication of nanopore arrays in freestanding SiN and graphene membranes. Nanotechnology 29, 145302 (2018).Google Scholar
45.Asghar, W., Ilyas, A., Billo, J., and Iqbal, S.: Shrinking of solid-state nanopores by direct thermal heating. Nanoscale Res. Lett. 6, 372 (2011).Google Scholar
46.Kwok, H., Briggs, K., and Tabard-Cossa, V.: Nanopore fabrication by controlled dielectric breakdown. PLoS One 9, e92880 (2014).Google Scholar
47.Pud, S., Verschueren, D., Vukovic, N., Plesa, C., Jonsson, M.P., and Dekker, C.: Self-aligned plasmonic nanopores by optically controlled dielectric breakdown. Nano Lett. 15, 71127117 (2015).Google Scholar
48.Wang, Y., Ying, C., Zhou, W., de Vreede, L., Liu, Z., and Tian, J.: Fabrication of multiple nanopores in a SiNx membrane via controlled breakdown. Sci. Rep. 8, (2018). Article no. 1234.Google Scholar
49.Kuan, A.T., Lu, B., Xie, P., Szalay, T., and Golovchenko, J.A.: Electrical pulse fabrication of graphene nanopores in electrolyte solution. Appl. Phys. Lett. 106, 203109 (2015).Google Scholar
50.Puczkarski, P., Swett, J.L., and Mol, J.A.: Graphene nanoelectrodes for biomolecular sensing. J. Mater. Res. 32, 30023010 (2017).Google Scholar
51.Lagerqvist, J., Zwolak, M., and Di Ventra, M.: Fast DNA sequencing via transverse electronic transport. Nano Lett. 6, 779782 (2006).Google Scholar
52.Prasongkit, J., Grigoriev, A., Pathak, B., Ahuja, R., and Scheicher, R.H.: Transverse conductance of DNA nucleotides in a graphene nanogap from first principles. Nano Lett. 11, 19411945 (2011).Google Scholar
53.Prasongkit, J., Grigoriev, A., Pathak, B., Ahuja, R., and Scheicher, R.H.: Theoretical study of electronic transport through DNA nucleotides in a double-functionalized graphene nanogap. J. Phys. Chem. C 117, 1542115428 (2013).Google Scholar
54.He, Y., Scheicher, R.H., Grigoriev, A., Ahuja, R., Long, S., Huo, Z., and Liu, M.: Enhanced DNA sequencing performance through edge-hydrogenation of graphene electrodes. Adv. Funct. Mater. 21, 26742679 (2011).Google Scholar
55.Amorim, R.G., Rocha, A.R., and Scheicher, R.H.: Boosting DNA recognition sensitivity of graphene nanogaps through nitrogen edge functionalization. J. Phys. Chem. C 120, 1938419388 (2016).Google Scholar
56.Ohshiro, T. and Umezawa, Y.: Complementary base-pair-facilitated electron tunneling for electrically pinpointing complementary nucleobases. Proc. Natl. Acad. Sci. USA 103, 1014 (2005).Google Scholar
57.Chang, S., He, J., Kibel, A., Lee, M., Sankey, O., Zhang, P., and Lindsay, S.: Tunnelling readout of hydrogen-bonding-based recognition. Nat. Nanotechnol. 4, 297301 (2009).Google Scholar
58.Tanaka, H. and Kawai, T.: Partial sequencing of a single DNA molecule with a scanning tunnelling microscope. Nat. Nanotechnol. 4, 518522 (2009).Google Scholar
59.Chang, S., Huang, S., He, J., Liang, F., Zhang, P., Li, S., Chen, X., Sankey, O., and Lindsay, S.: Electronic signatures of all four DNA nucleosides in a tunneling gap. Nano Lett. 10, 10701075 (2010).Google Scholar
60.Di Ventra, M. and Taniguchi, M.: Decoding DNA, RNA and peptides with quantum tunnelling. Nat. Nanotechnol. 11, 117126 (2016).Google Scholar
61.Tsutsui, M., Taniguchi, M., and Kawai, T.: Transverse field effects on DNA-sized particle dynamics. Nano Lett. 9, 16591662 (2009).Google Scholar
62.Tsutsui, M., Taniguchi, M., Yokota, K., and Kawai, T.: Identifying single nucleotides by tunnelling current. Nat. Nanotechnol. 5, 286290 (2010).Google Scholar
63.Tsutsui, M., Rahong, S., Iizumi, Y., Okazaki, T., Taniguchi, M., and Kawai, T.: Single-molecule sensing electrode embedded in-plane nanopore. Sci. Rep. 1, (2011). Article no. 46.Google Scholar
64.Tsutsui, M., Matsubara, K., Ohshiro, T., Furuhashi, M., Taniguchi, M., and Kawai, T.: Electrical detection of single methylcytosines in a DNA oligomer. J. Am. Chem. Soc. 133, 91249128 (2011).Google Scholar
65.Pang, P., Ashcroft, B.A., Song, W., Zhang, P., Biswas, S., Qing, Q., Yang, J., Nemanich, R.J., Bai, J., Smith, J.T., Reuter, K., Balagurusamy, V.S.K., Astier, Y., Stolovitzky, G., and Lindsay, S.: Fixed-gap tunnel junction for reading DNA nucleotides. ACS Nano 8, 1199412003 (2014).Google Scholar
66.Prins, F., Barreiro, A., Ruitenberg, J.W., Seldenthuis, J.S., Aliaga-Alcalde, N., Vandersypen, L.M.K., and van der Zant, H.S.J.: Room-temperature gating of molecular junctions using few-layer graphene nanogap electrodes. Nano Lett. 11, 46074611 (2011).Google Scholar
67.Caneva, S., Gehring, P., Garca-Surez, V.M., Garca-Fuente, A., Stefani, D., Olavarria-Contreras, I.J., Ferrer, J., Dekker, C., and van der Zant, H.S.J.: Mechanically controlled quantum interference in graphene break junctions. arXiv:1803.05642 March 2018.Google Scholar
68.Wang, H.M., Zheng, Z., Wang, Y.Y., Qiu, J.J., Guo, Z.B., Shen, Z.X., and Yu, T.: Fabrication of graphene nanogap with crystallographically matching edges and its electron emission properties. Appl. Phys. Lett. 96, 023106 (2010).Google Scholar
69.Bellunato, A., Vrbica, S.D., Sabater, C., de Vos, E.W., Fermin, R., Kanneworff, K.N., Galli, F., van Ruitenbeek, J.M., and Schneider, G.F.: Dynamic tunneling junctions at the atomic intersection of two twisted graphene edges. Nano Lett. 18, 25052510 (2018).Google Scholar
70.Lau, C.S., Mol, J.A., Warner, J.H., and Briggs, G.A.D.: Nanoscale control of graphene electrodes. Phys. Chem. Chem. Phys. 16, 2039820401 (2014).Google Scholar
71.El Abbassi, M., Pósa, L., Makk, P., Nef, C., Thodkar, K., Halbritter, A., and Calame, M.: From electroburning to sublimation: substrate and environmental effects in the electrical breakdown process of monolayer graphene. Nanoscale 9, 1731217317 (2017).Google Scholar
72.Patel, H.N., Carroll, I., Lopez, R., Sankararaman, S., Etienne, C., Kodigala, S.R., Paul, M.R., and Postma, H.W.C.: DNA-graphene interactions during translocation through nanogaps. Plos One 12, e0171505 (2017).Google Scholar
73.Cai, J., Ruffieux, P., Jaafar, R., Bieri, M., Braun, T., Blankenburg, S., Muoth, M., Seitsonen, A.P., Saleh, M., Feng, X., Mllen, K., and Fasel, R.: Atomically precise bottom-up fabrication of graphene nanoribbons. Nature 466, 470473 (2010).Google Scholar
74.Xu, Q., Wu, M.-Y., Schneider, G.F., Houben, L., Malladi, S.K., Dekker, C., Yucelen, E., Dunin-Borkowski, R.E., and Zandbergen, H.W.: Controllable atomic scale patterning of freestanding monolayer graphene at elevated temperature. ACS Nano 7, 15661572 (2013).Google Scholar
75.Arcadia, C.E., Reyes, C.C., and Rosenstein, J.K.: In situ nanopore fabrication and single-molecule sensing with microscale liquid contacts. ACS Nano 11, 49074915 (2017).Google Scholar
76.Cho, Y., Min, S.K., Kim, W.Y., and Kim, K.S.: The origin of dips for the graphene-based DNA sequencing device. Phys. Chem. Chem. Phys. 13, 14293 (2011).Google Scholar
77.Bai, J., Duan, X., and Huang, Y.: Rational fabrication of graphene nanoribbons using a nanowire etch mask. Nano Lett. 9, 20832087 (2009).Google Scholar
78.Jiao, L., Zhang, L., Wang, X., Diankov, G., and Dai, H.: Narrow graphene nanoribbons from carbon nanotubes. Nature 458, 877880 (2009).Google Scholar
79.Han, M.Y., zyilmaz, B., Zhang, Y., and Kim, P.: Energy band-gap engineering of graphene nanoribbons. Phys. Rev. Lett. 98, 206805 (2007).Google Scholar
80.Wang, X. and Dai, H.: Etching and narrowing of graphene from the edges. Nat. Chem. 2, 661665 (2010).Google Scholar
81.Fischbein, M.D. and Drndić, M.: Electron beam nanosculpting of suspended graphene sheets. Appl. Phys. Lett. 93, 113107 (2008).Google Scholar
82.Bell, D.C., Lemme, M.C., Stern, L.A., Williams, J.R., and Marcus, C.M.: Precision cutting and patterning of graphene with helium ions. Nanotechnology 20, 455301 (2009).Google Scholar
83.Xia, D., Yan, J., and Hou, S.: Fabrication of nanofluidic biochips with nanochannels for applications in DNA analysis. Small 8, 27872801 (2012).Google Scholar
84.Duan, C., Wang, W., and Xie, Q.: Review article: Fabrication of nanofluidic devices. Biomicrofluidics 7, 026501 (2013).Google Scholar
85.Hibara, A., Saito, T., Kim, H.-B., Tokeshi, M., Ooi, T., Nakao, M., and Kitamori, T.: Nanochannels on a fused-silica microchip and liquid properties investigation by time-resolved fluorescence measurements. Anal. Chem. 74, 61706176 (2002).Google Scholar
86.Levy, S.L., Mannion, J.T., Cheng, J., Reccius, C.H., and Craighead, H.G.: Entropic unfolding of DNA molecules in nanofluidic channels. Nano Lett. 8, 38393844 (2008).Google Scholar
87.Riehn, R., Austin, R.H., and Sturm, J.C.: A nanofluidic railroad switch for DNA. Nano Lett. 6, 19731976 (2006).Google Scholar
88.Xia, D., Ku, Z., Lee, S.C., and Brueck, S.R.J.: Nanostructures and functional materials fabricated by interferometric lithography. Adv. Mater. 23, 147179 (2010).Google Scholar
89.Guo, L.J., Cheng, X., and Chou, C.-F.: Fabrication of size-controllable nanofluidic channels by nanoimprinting and its application for DNA stretching. Nano Lett. 4, 6973 (2004).Google Scholar
90.Liang, X., Morton, K.J., Austin, R.H., and Chou, S.Y.: Single sub-20 nm wide, centimeter-long nanofluidic channel fabricated by novel nanoimprint mold fabrication and direct imprinting. Nano Lett. 7, 37743780 (2007).Google Scholar
91.Liang, X. and Chou, S.Y.: Nanogap detector inside nanofluidic channel for fast real-time label-free DNA analysis. Nano Lett. 8, 14721476 (2008).Google Scholar
92.Maleki, T., Mohammadi, S., and Ziaie, B.: A nanofluidic channel with embedded transverse nanoelectrodes. Nanotechnology 20, 105302 (2009).Google Scholar
93.Schneider, G.F., Calado, V.E., Zandbergen, H., Vandersypen, L.M.K., and Dekker, C.: Wedging transfer of nanostructures. Nano Lett. 10, 19121916 (2010).Google Scholar
94.Wang, Y., Zheng, Y., Xu, X., Dubuisson, E., Bao, Q., Lu, J., and Loh, K.P.: Electrochemical delamination of CVD-grown graphene film: toward the recyclable use of copper catalyst. ACS Nano 5, 99279933 (2011).Google Scholar
95.Moser, J., Barreiro, A., and Bachtold, A.: Current-induced cleaning of graphene. Appl. Phys. Lett. 91, 163513 (2007).Google Scholar
96.Ishigami, M., Chen, J.H., Cullen, W.G., Fuhrer, M.S., and Williams, E.D.: Atomic structure of graphene on SiO2. Nano Lett. 7, 16431648 (2007).Google Scholar
97.Fu, W., Feng, L., Panaitov, G., Kireev, D., Mayer, D., Offenhusser, A., and Krause, H.-J.: Biosensing near the neutrality point of graphene. Sci. Adv. 3, e1701247 (2017).Google Scholar
98.Sun, L., Diaz-Fernandex, Y.A., Gschneidtner, T.A., Westerlund, F., Lara-Avila, S., and Moth-Pouslen, K.: Single molecule electronics: from chemical design to functional devices. Chem. Soc. Rev. 43, 73787411.Google Scholar