Sains Malaysiana 46(7)(2017): 1125–1139

http://dx.doi.org/10.17576/jsm-2017-4607-16

 

Graphene for Biomedical Applications: A Review

(Grafin untuk Aplikasi Bioperubatan: Suatu Sorotan)

 

AZRUL AZLAN HAMZAH*, REENA SRI SELVARAJAN & BURHANUDDIN YEOP MAJLIS

 

Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan, Malaysia

 

Diserahkan: 27 Disember 2016/Diterima: 13 Februari 2017

 

ABSTRACT

Since its discovery in 2004, graphene has enticed engineers and researchers from various fields to explore its possibilities to be incepted into various devices and applications. Graphene is deemed a ‘super’ material by researchers due to its extraordinary strength, extremely high surface-to-mass ratio and superconducting properties. Nonetheless, graphene has yet to find plausible footing as an electronics material. In biomedical field, graphene has proved useful in tissue engineering, drug delivery, cancer teraphy, as a component in power unit for biomedical implants and devices and as a vital component in biosensors. Graphene is used as scaffolding for tissue regeneration in stem cell tissue engineering, as active electrodes in supercapacitor for powering wearable and implantable biomedical devices and as detectors in biosensors. In tissue engineering, the extreme strength of monolayer graphene enables it to hold stem cell tissues as scaffold during in-vitro cell regeneration process. In MEMS supercapacitor, graphene's extremely high surface-to-mass ratio enables it to be used as electrodes in order to increase the power unit's energy and power densities. A small yet having high energy and power densities cell is needed to power often space constrainted biomedical devices. In FET biosensors, graphene acts as detector electrodes, owing to its superconductivity property. Graphene detector electrodes is capable of detecting target molecules at a concentration level as low as 1 pM, making it the most sensitive biosensor available today. Graphene continues to envisage unique and exciting applications for biomedical field, prompting continuous research which results and implementation could benefit the general public in decades to come.

 

Keywords: Biomedical applications; FET biosensor; graphene; scaffolding; supercapacitor; tissue engineering

 

ABSTRAK

Sejak penemuannya pada tahun 2004, grafin telah menarik minat para jurutera dan penyelidik daripada pelbagai bidang untuk mengkaji kebolehaplikasiannya di dalam pelbagai peranti dan penggunaan. Grafin dianggap sebagai bahan super oleh penyelidik disebabkan kekuatannya yang amat tinggi, nisbah luas permukaan kepada jisim yang sangat besar dan sifat superkonduktornya. Walau bagaimanapun, grafin masih belum diakui sebagai bahan elektronik. Di dalam bidang bioperubatan, grafin telah digunakan di dalam kejuruteraaan tisu, penyampaian ubat, rawatan kanser, sebagai komponen unit kuasa untuk implan dan peranti bioperubatan dan sebagai komponen penting di dalam pengesan bio. Grafin digunakan sebagai perancah untuk pembinaan semula tisu di dalam kejuruteraan tisu sel induk, sebagai elektrod aktif di dalam superkapasitor untuk menghidupkan peranti bioperubatan bolehpakai dan implan serta sebagai unsur pengesanan di dalam pengesan bio. Di dalam bidang kejuruteraan tisu, kekuatan grafin selapis yang amat tinggi membolehkannya memegang tisu-tisu sel induk sebagai perancah semasa proses pertumbuhan semula sel secarain-vitro. Di dalam superkapasitor MEMS, nisbah luas permukaan kepada jisim grafin yang tinggi membolehkan penggunaannya sebagai elektrod untuk meningkatkan ketumpatan tenaga dan kuasa unit tersebut. Sel kuasa yang kecil tetapi mempunyai ketumpatan tenaga dan kuasa yang tinggi sering diperlukan di dalam peranti bioperubatan yang acapkali terbatas oleh saiz yang kecil. Di dalam pengesan bio FET, grafin yang mempunyai sifat konduktiviti super berfungsi sebagai elektrod pengesan. Elektrod pengesan grafin boleh mengesan molekul sasaran dengan kepekatan serendah 1 pM, menjadikannya pengesan bio paling sensitif pada masa kini. Grafin terus merealisasikan kegunaan unik dan menarik di dalam bidang bioperubatan, yang seterusnya menarik minat para penyelidik untuk terus menghasilkan penggunaan yang berguna untuk masyarakat pada masa akan datang.

 

Kata kunci: Aplikasi bioperubatan; grafin; kejuruteraan tisu; pengesan bio FET; sokongan; superkapasitor

RUJUKAN

 

Abidin, H.E.Z., Hamzah, A.A., Mohamed, M.A., Majlis, B.Y. & Marsi, N. 2015. Electrical performances based on two different structured of micro supercapacitor electrodes. IEEE Regional Symposium on Micro and Nano Electronics (RSM) 4: 5-8. doi:10.1109/RSM.2015.7354977.

Abidin, H.E.Z., Hamzah, A.A. & Majlis, B.Y. 2011. Design of interdigital structured supercapacitor for powering biomedical devices. 2011 IEEE Regional Symposium on Micro and Nanoelectronics, RSM 2011 - Programme and Abstracts. pp. 88-91. doi:10.1109/RSM.2011.6088298.

Adzhri, R., Md Arshad, M.K., Gopinath, S.C.B., Ruslinda, A.R., Fathil, M.F.M., Ayub, R.M., M. Nuhaizan, Mohd Nor & Voon, C.H. 2016. High-performance integrated field-effect transistor-based sensors. Analytica Chimica Acta917: 1-18. doi:10.1016/j.aca.2016.02.042.

Ahadian, S., Obregón, R., Ramón-Azcón, J., Salazar, G., Shiku, H., Ramalingam, M. & Matsue, T. 2016. Carbon nanotubes and graphene-based nanomaterials for stem cell differentiation and tissue regeneration. Journal of Nanoscience and Nanotechnology 16(9): 8862-8880. doi:10.1166/jnn.2016.12729.

Akhavan, O. 2016. Graphene scaffolds in progressive nanotechnology/stem cell-based tissue engineering of nervous systems. J. Mater. Chem. B 4: 3169-3190. doi:10.1039/C6TB00152A.

Akhavan, O., Ghaderi, E., Abouei, E., Hatamie, S. & Ghasemi, E. 2014. Accelerated differentiation of neural stem cells into neurons on ginseng-reduced graphene oxide sheets. Carbon 66: 395-406. doi:10.1016/j.carbon.2013.09.015.

Ali, U., Karim, K.J.B.A. & Buang, N.A. 2015. A review of the properties and applications of poly(methyl methacrylate) (PMMA). Polymer Reviews 55(10): 678-705. doi:10.1080/ 15583724.2015.1031377.

Amine, A., Mohammadi, H., Bourais, I. & Palleschi, G. 2006. Enzyme inhibition-based biosensors for food safety and environmental monitoring. Biosensors and Bioelectronics 21(8): 1405-1423. doi:10.1016/j.bios.2005.07.012.

Bae, S., Kim, H., Lee, Y., Xu, X., Park, J.-S., Zheng, Y., Balakrishnan, J., Lei, T., Kim, H.R., Song, Young II, Kim, Y-K., Kim, K.S., Özyilmaz, B., Ahn, J-H., Hong, B.H. & Iijima, S. 2010. Roll-to-roll production of 30-inch graphene films for transparent electrodes. Nature Nanotechnology 5(8): 574-578. doi:10.1038/nnano.2010.132.

Castro Neto, A.H., Guinea, F., Peres, N.M.R., Novoselov, K.S. & Geim, A.K. 2009. The electronic properties of graphene. Reviews of Modern Physics 81(1): 109-162. doi:10.1103/ RevModPhys.81.109.

Chaudhary, R., Sharma, A., Sinha, S., Yadav, J., Sharma, R., Mukhiya, R. & Khanna, V.K. 2016. Fabrication and characterisation of Al gate n-metal-oxide-semiconductor field-effect transistor, on-chip fabricated with silicon nitride ion-sensitive field-effect transistor. IET Computers and Digital Techniques 10(5): 268-272. doi:10.1049/iet-cdt.2015.0174.

Chen, T-Y., Loan, P.T.K., Hsu, C-L., Lee, Y-H., Wang, J. T-W., Wei, K-H., Lin, C-T. & Li, L.J. 2013. Label-free detection of DNA hybridization using transistors based on CVD grown graphene. Biosensors & Bioelectronics 41: 103-109. doi:10.1016/j.bios.2012.07.059.

Cheng, Q., Tang, J., Ma, J., Zhang, H., Shinya, N. & Qin, L.C. 2011. Graphene and carbon nanotube composite electrodes for supercapacitors with ultra-high energy density. Physical Chemistry Chemical Physics 13(39): 17615-17624. doi:10.1039/c1cp21910c.

Choi, W., Lahiri, I., Seelaboyina, R. & Kan, Y.S. 2010. Synthesis of graphene and its applications: A review. Critical Reviews in Solid State and Materials Sciences 35(1): 52-71. doi:10.1080/10408430903505036.

Craciun, M.F., Russo, S., Yamamoto, M. & Tarucha, S. 2011. Tuneable electronic properties in graphene. Nano Today 6(1): 42-60. doi:10.1016/j.nantod.2010.12.001.

Cui, Y. 2013. Nanowire nanosensors for highly sensitive and selective detection of biological and chemical species. Science 293(5533): 1289-1292. doi:10.1126/science.1062711.

Dong, X., Shi, Y., Huang, W., Chen, P. & Li, L.J. 2010. Electrical detection of DNA hybridization with single-base specificity using transistors based on CVD-grown graphene sheets. Advanced Materials 22(14): 1649-1653. doi:10.1002/ adma.200903645.

Dreyer, D.R., Ruoff, R.S. & Bielawski, C.W. 2010. From conception to realization: An historial account of graphene and some perspectives for its future. Angewandte Chemie - International Edition 49(49): 9336-9344. doi:10.1002/ anie.201003024.

Dubal, D.P., Ayyad, O., Ruiz, V. & Gómez-Romero, P. 2015. Hybrid energy storage: The merging of battery and supercapacitor chemistries. Chem. Soc. Rev. 44(7): 1777- 1790. doi:10.1039/C4CS00266K.

Feng, L., Chen, Y., Ren, J. & Qu, X. 2011. A graphene functionalized electrochemical aptasensor for selective label-free detection of cancer cells. Biomaterials 32(11): 2930-2937. doi:10.1016/j.biomaterials.2011.01.002.

Fiori, G. & Iannaccone, G. 2009. Ultralow-voltage bilayer graphene tunnel FET. IEEE Electron Device Letters 30(10): 1096-1098. doi:10.1109/LED.2009.2028248.

Gao, D., Li, M., Li, H., Li, C., Zhu, N. & Yang, B. 2016. Sensitive detection of biomolecules and DNA bases based on graphene nanosheets. Journal of Solid State Electrochemistry 21(3): 813-821. doi:10.1007/s10008-016-3423-0.

Ge, C., Li, H., Li, M., Li, C., Wu, X. & Yang, B. 2015. Synthesis of a ZnO nanorod/CVD graphene composite for simultaneous sensing of dihydroxybenzene isomers. Carbon 95: 1-9. doi:10.1016/j.carbon.2015.08.006.

Innova Research. 2015. Overcapacity will soon reshape graphene industry landscape. https://www.newswire.com/ news/overcapacity-will-soon-reshape-graphene-production-landscape. Accessed on February 6, 2017.

Novoselov, K.S., Jiang, Z., Zhang, Y., Morozov, S.V., Stormer, H.L., Zeitler, U., Maan, J.C., Boebinger, G.S., Kim, P. & Geim, A.K. 2007. Room temperature quantum hall effect in graphene. Science 315(5817): 1379. DOI: 10.1126/ science.1137201.

Goenka, S., Sant, V. & Sant, S. 2014. Graphene-based nanomaterials for drug delivery and tissue engineering. Journal of Controlled Release 173(1): 75-88. doi:10.1016/j. jconrel.2013.10.017.

González, Z., Vizireanu, S., Dinescu, G., Blanco, C. & Santamaría, R. 2012. Carbon nanowalls thin films as nanostructured electrode materials in vanadium redox flow batteries. Nano Energy 1(6): 833-839. doi:10.1016/j.nanoen.2012.07.003.

Guo, S.R., Lin, J., Penchev, M., Yengel, E., Ghazinejad, M., Ozkan, C.S. & Ozkan, M. 2011. Label free DNA detection using large area graphene based field effect transistor biosensors. Journal of Nanoscience and Nanotechnology 11(6): 5258-5263. doi:10.1166/jnn.2011.3885.

Hass, J., de Heer, W.A. & Conrad, E.H. 2008. The growth and morphology of epitaxial multilayer graphene. Journal of Physics: Condensed Matter 20(32): 323202. doi:10.1088/0953-8984/20/32/323202.

Hassan, S., Suzuki, M., Mori, S. & El-Moneim, A.A. 2014. MnO2/ carbon nanowalls composite electrode for supercapacitor application. Journal of Power Sources 249(January): 21-27. doi:10.1016/j.jpowsour.2013.10.097.

Huang, Y., Dong, X., Shi, Y., Li, C.M., Li, L.J. & Chen, P. 2010. Nanoelectronic biosensors based on CVD grown graphene. Nanoscale 2(8): 1485-1488. doi:10.1039/c0nr00142b.

Hwang, J., Yoon, T., Jin, S.H., Lee, J., Kim, T.S., Hong, S.H. & Jeon, S. 2013. Enhanced mechanical properties of graphene/copper nanocomposites using a molecular-level mixing process. Advanced Materials 25(46): 6724-6729. doi:10.1002/adma.201302495.

Kang, S.J., Kocabas, C., Ozel, T., Shim, M., Pimparkar, N., Alam, M.A., Rotkin, S.V. & Rogers, J.A. 2007. High-performance electronics using dense, perfectly aligned arrays of single-walled carbon nanotubes. Nature Nanotechnology 2(4): 230-236. doi:10.1038/nnano.2007.77.

Kedzierski, J. 2008. Epitaxial graphene transistors on SiC substrates. IEEE Trans. Electron Devices, 55(8): 2078-2085. http://dx.doi.org/10.1109/TED.2008.926593.

Kim, J.P., Lee, B.Y., Lee, J., Hong, S. & Sim, S.J. 2009. Enhancement of sensitivity and specificity by surface modification of carbon nanotubes in diagnosis of prostate cancer based on carbon nanotube field effect transistors. Biosensors and Bioelectronics 24(11): 3372-3378. doi:10.1016/j.bios.2009.04.048.

Lee, S.K., Kim, H. & Shim, B.S. 2013. Graphene: An emerging material for biological tissue engineering. Carbon Letters 14(2): 63-75. doi:10.5714/CL.2013.14.2.063.

Lemme, M.C., Member, S., Echtermeyer, T.J., Baus, M. & Kurz, H. 2007. A graphene field-effect device. IEEE Electron Device Letters 28(4): 282-284.

Li, N., Zhang, Q., Gao, S., Song, Q., Huang, R., Wang, L., Liu, L., Dai, J., Tang, M. & Cheng, G. 2013. Three-dimensional graphene foam as a biocompatible and conductive scaffold for neural stem cells. Scientific Reports 3: 1604. doi:10.1038/ srep01604.

Li, X. & Wei, B. 2013. Supercapacitors based on nanostructured carbon. Nano Energy 2(2): 159-173. doi:10.1016/j. nanoen.2012.09.008.

Liu, C., Yu, Z., Neff, D., Zhamu, A. & Jang, B.Z. 2010a. Graphene-based supercapacitor with an ultrahigh energy density. Nano Letters 10(12): 4863-4868. doi:10.1021/ nl102661q.

Liu, C., Yu, Z., Neff, D., Zhamu, A. & Jang, B.Z. 2010b. Graphene-based supercapacitor with an ultrahigh energy density - SI. Nano Letters 10(12): 4863-4868. doi:10.1021/ nl102661q.

Liu, S. & Guo, X. 2012. Carbon nanomaterials field-effect-transistor-based biosensors. NPG Asia Materials 4(8): e23. doi:10.1038/am.2012.42.

Lu, M., Lee, D., Xue, W. & Cui, T. 2009. Flexible and disposable immunosensors based on layer-by-layer self-assembled carbon nanotubes and biomolecules. Sensors and Actuators A: Physical 150(2): 280-285. doi:10.1016/j.sna.2008.12.021.

Lund, A.W., Yener, B., Stegemann, J.P. & Plopper, G.E. 2009. The natural and engineered 3D microenvironment as a regulatory cue during stem cell fate determination. Tissue Engineering. Part B, Reviews 15(3): 371-380. doi:10.1089/ ten.teb.2009.0270.

Maehashi, K., Katsura, T., Kerman, K., Takamura, Y., Matsumoto, K. & Tamiya, E. 2007. Label-free protein biosensor based on aptamer-modified carbon nanotube field-effect transistors. Analytical Chemistry 79(2): 782-787. doi:10.1021/ ac060830g.

Mannoor, M.S., Tao, H., Clayton, J.D., Sengupta, A., Kaplan, D.L., Naik, R.R., Verma, N., Omenetto, F.G. & McAlpine, M.C. 2014. Graphene-based wireless bacteria detection on tooth enamel. Nature Mater. XXXIII(2): 81-87. doi:10.1007/ s13398-014-0173-7.2.

Mao, S., Yu, K., Chang, J., Steeber, D.A., Ocola, L.E. & Chen, J. 2013. Direct growth of vertically-oriented graphene for field-effect transistor biosensor. Scientific Reports 3: 1696. doi:10.1038/srep01696.

Mao, S., Yu, K., Lu, G. & Chen, J. 2011. Highly sensitive protein sensor based on thermally-reduced graphene oxide field-effect transistor. Nano Research 4(10): 921-930. doi:10.1007/ s12274-011-0148-3.

Nguyen, T., Pei, R., Landry, D.W., Stojanovic, M.N. & Lin, Q. 2011. Microfluidic aptameric affinity sensing of vasopressin for clinical diagnostic and therapeutic applications. Sensors and Actuators B: Chemical 154(1): 59-66. doi:10.1016/j. snb.2009.10.032.

Ohno, Y., Maehashi, K. & Matsumoto, K. 2010. Label-free biosensors based on aptamer-modified graphene field-effect transistors. Journal of the American Chemical Society 132(51): 18012-18013. doi:10.1021/ja108127r.

Ohno, Y., Maehashi, K., Yamashiro, Y. & Matsumoto, K. 2009. Electrolyte-gated graphene field-effect transistors for detecting pH and protein adsorption. Nano Lett. 9(9): 3318-3322.

Park, S.Y., Park, J., Sim, S.H., Sung, M.G., Kim, K.S., Hong, B.H. & Hong, S. 2011. Enhanced differentiation of human neural stem cells into neurons on graphene. Advanced Materials 23(36): 263-267. doi:10.1002/adma.201101503.

Pei, S. & Cheng, H.M. 2012. The reduction of graphene oxide. Carbon 50(9): 3210-3228. doi:10.1016/j.carbon.2011.11.010.

Peng, Z., Lin, J., Ye, R., Samuel, E.L.G. & Tour, J.M. 2015. Flexible and stackable laser-induced graphene supercapacitors. ACS Applied Materials and Interfaces 7(5): 3414-3419. doi:10.1021/am509065d.

Peres, N.M.R. 2009. The electronic properties of graphene and its bilayer. Vacuum 83(10): 1248-1252. doi:10.1016/j. vacuum.2009.03.018.

Ping, J., Vishnubhotla, R., Vrudhula, A. & Johnson, A.T.C. 2016. Scalable production of high sensitivity, label-free DNA biosensors based on back-gated graphene field effect transistors. ACS Nano acsnano.6b04110. doi:10.1021/ acsnano.6b04110.

Ping, J., Zhou, Y., Wu, Y., Papper, V., Boujday, S., Marks, R.S. & Steele, T.W.J. 2015. Recent advances in aptasensors based on graphene and graphene-like nanomaterials. Biosensors and Bioelectronics 64: 373-385. doi:10.1016/j.bios.2014.08.090.

Rakheja, S. & Sengupta, P. 2016. Gate-voltage tunability of plasmons in single-layer graphene structures - Analytical description, impact of interface states, and concepts for terahertz devices. IEEE Transactions on Nanotechnology 15(1): 113-121. doi:10.1109/TNANO.2015.2507142.

Ren, W. & Cheng, H. 2014. The global growth of graphene. Nature Nanotechnology 9: 726-730. doi:10.1038/nnano.2014.229.

Iro, Z.S., Subramani, C. & Dash, S.S. 2016. A brief review on electrode materials for supercapacitor. International Journal of Electrochemical Science 11: 10628-10643. doi:10.20964/2016.12.50.

Simon, P. & Gogotsi, Y. 2008. Materials for electrochemical capacitors. Nature Materials 7(11): 845-854. doi:10.1038/ nmat2297.

Sordan, R., Traversi, F. & Russo, V. 2009. Logic gates with a single graphene transistor. Applied Physics Letters 94: 073305. doi:10.1063/1.3079663.

Star, A., Tu, E., Niemann, J., Gabriel, J.C.P., Joiner, C.S. & Valcke, C. 2006. Label-free detection of DNA hybridization using carbon nanotube network field-effect transistors. Proceedings of the National Academy of Sciences 103(4): 921-926. doi:10.1073/pnas.0504146103.

Tan, Y.B. & Lee, J.M. 2013. Graphene for supercapacitor applications. Journal of Materials Chemistry A 1(47): 14814- 14843. doi:10.1039/c3ta12193c.

Taychatanapat, T., Watanabe, K., Taniguchi, T. & Jarillo-Herrero, P. 2011. Quantum hall effect and Landau level crossing of Dirac fermions in trilayer graphene. Nature Physics 7(8): 621-625. doi:10.1038/nphys2008.

Tran, T.T. & Mulchandani, A. 2016. Carbon nanotubes and graphene nano field-effect transistor-based biosensors. Trends in Analytical Chemistry 79: 222-232. doi:10.1016/j. trac.2015.12.002.

Urmann, K., Modrejewski, J. & Scheper, T. 2017. Aptamer-modified nanomaterials: Principles and applications. BioNanoMat 18(1-2): 20160012. doi:10.1515/bnm-2016-0012.

Viswanathan, S., Narayanan, T.N., Aran, K., Fink, K.D., Paredes, J., Ajayan, P.M., Filipek, S., Miszta, P., Cumhur Tekin, H., Inci, F., Demirci, U., Li, P., Bolotin, K.I., Liepmann, D. & Renugoplakrishnan, V. 2015. Graphene-protein field effect biosensors: Glucose sensing. Materials Today 18(9): 513-522. doi:10.1016/j.mattod.2015.04.003.

Wang, C., Kim, J., Zhu, Y., Yang, J., Lee, G.H., Lee, S., Yu, J., Pei, R., Liu, G., Nuckolls, C. Hone, J. & Lin, Q. 2015. An aptameric graphene nanosensor for label-free detection of small-molecule biomarkers. Biosensors and Bioelectronics 71: 222-229. doi:10.1016/j.bios.2015.04.025.

Wang, J., Ding, B., Hao, X., Xu, Y., Wang, Y., Shen, L., Dou, H. & Zhang, X. 2016. A modified molten-salt method to prepare graphene electrode with high capacitance and low self-discharge rate. Carbon 102: 255-261. doi:10.1016/j. carbon.2016.02.047.

Wang, Y., Wang, Y., Chen, J., Guo, H., Liang, K., Marcus, K., Peng, Q.L., Zhang, J. & Feng, Z.S. 2016. A facile process combined with inkjet printing, surface modification and electroless deposition to fabricate adhesion-enhanced copper patterns on flexible polymer substrates for functional flexible electronics. Electrochimica Acta218: 24-31. doi:10.1016/j. electacta.2016.08.143.

Xu, G., Abbott, J., Qin, L., Yeung, K.Y.M., Song, Y., Yoon, H., Kong, J. & Ham, D. 2014. Electrophoretic and field-effect graphene for all-electrical DNA array technology. Nature Communications 5: 4866. doi:10.1038/ncomms5866.

Yan, F., Zhang, M. & Li, J. 2014. Solution-gated graphene transistors for chemical and biological sensors. Advanced Healthcare Materials 3(3): 313-331. doi:10.1002/ adhm.201300221.

Yang, F., Murugan, R., Wang, S. & Ramakrishna, S. 2005. Electrospinning of nano/micro scale poly(l-lactic acid) aligned fibers and their potential in neural tissue engineering. Biomaterials 26(15): 2603-2610. doi:10.1016/j. biomaterials.2004.06.051.

Yang, J., Zhu, J., Pei, R., Oliver, J.A., Landry, D.W., Stojanovic, M.N. & Lin, Q. 2016. Integrated microfluidic aptasensor for mass spectrometric detection of vasopressin in human plasma ultrafiltrate. Analytical Methods 8(26): 5190-5196. doi:10.1039/c5ay02979a.

Yang, W., Ratinac, K.R., Ringer, S.R., Thordarson, P., Gooding, J.J. & Braet, F. 2010. Carbon nanomaterials in biosensors: Should you use nanotubes or graphene. Angewandte Chemie - International Edition 49(12): 2114-2138. doi:10.1002/ anie.200903463.

Zhang, A. & Zheng, G. 2015. Semiconductor nanowires for biosensors. In Semiconductor Nanowires: Materials, Synthesis, Characterization and Applications. Cambridge: Woodhead Publishing. pp. 471-490. doi:10.1016/B978-1- 78242-253-2.00017-7.

Zhang, B. & Cui, T. 2011. An ultrasensitive and low-cost graphene sensor based on layer-by-layer nano self-assembly. Applied Physics Letters 98(7): 2011-2014. doi:10.1063/1.3557504.

Zheng, C., Huang, L., Zhang, H., Sun, Z., Zhang, Z. & Zhang, G.J. 2015. Fabrication of ultrasensitive field-effect transistor DNA biosensors by a directional transfer technique based on CVD-grown graphene. ACS Applied Materials and Interfaces 7(31): 16953-16959. doi:10.1021/acsami.5b03941.

Zheng, G., Patolsky, F., Cui, Y., Wang, W.U. & Lieber, C.M. 2005. Multiplexed electrical detection of cancer markers with nanowire sensor arrays. Nature Biotechnology 23(10): 1294-1301. doi:10.1038/nbt1138.

 

 

*Pengarang untuk surat-menyurat; email: azlanhamzah@ukm.edu.my