酪胺酸(L-Tyrosine, TY)為人體中重要的胺基酸，亦為神經傳導物質多巴胺(Dopamine, DA)的前驅物，兩者皆影響著人類的神經思考系統與情緒管理因子，許多身心理疾病與它們的濃度習習相關，即時監測體內多巴胺與酪胺酸的濃度，益於早期預防精神與壓力疾病。採用電化學方法偵測多巴胺與酪胺酸為相對簡單、快速的感測方式。由於多巴胺在正常人尿液中濃度範圍為0~5 μΜ，酪胺酸濃度為0.39~1.5m M，其差距過大，發展出的感測器需具有較高的多巴胺靈敏度與較廣的酪胺酸偵測濃度範圍，且能同時避免抗壞血酸與尿酸的訊號干擾。
本研究以低成本且快速的方法，在磷酸中以循環伏安法在筆芯電極表面產生含氧官能基，藉此提升電極表面活性並大幅地增加多巴胺與酪胺酸之感測電流，修飾電極的多巴胺感測電流從原本裸電極的4.69 μA，提升為84.15μA；而酪胺酸電流則從32.8 μA提升為89.98 μA，經XPS儀器分析，電極表面產生三種含氧官能基C-OH、C = O、O = C-O；其中氧含量經EDS量測，從原來的1.68 %，增加為10.45 %，提升6.2倍。修飾後電極的黃血鹽反應速率常數經擬可逆參數圖及公式計算為 3.9×10-3( cm/s )，活性面積為6.2×10-3( cm2 )，分別為裸電極的5倍與2倍，經方波伏安法同時偵測多巴胺與酪胺酸時，多巴胺與干擾物尿酸電位差為141mV；酪胺酸與尿酸電位差為313 mV，彼此間無互相干擾。
本研究中，以0.05M磷酸 (pH 1.83)、循環伏安法的掃描範圍-0.3~2.2 V (vs. Ag/AgCl)、掃描速率50 mV/s、掃描7圈，所得的電生成氧化筆芯經方波伏安法(Square wave Voltammetry, SWV)結果顯示，此條件可得最高的多巴胺靈敏度18.79 μA/μΜ，感測濃度範圍1~7 μΜ，偵測下限0.11 μΜ (S/N=3)，此時，酪胺酸靈敏度0.934 μA/μΜ，感測濃度範圍30~ 200 μΜ，偵測下限5.54 μΜ ( S/N = 3 )。

A simple and low-cost method for simultaneous detection of dopamine (DA) and L-tyrosine (TY) in urine was performed with a graphite oxides modified graphite pencil electrode (GrO/GPE). Graphite-oxide (GrO) was directly generated by cyclic voltammetry (CV) on the surface of a GPE. The oxygen-containing functional groups enhanced the electroactive surface for oxidations of DA and TY. Several decisive preparation parameters were optimized for the highest sensitivity of DA and TY. The linear ranges foe detection with square wave voltammetry (SWV) were 1-7 μM and 30-200 μM for DA and TY, respectively. The lowest detection limits for DA and TY were 0.11μM and 5.54μM, respectively.

[1] 楊穎鋒, "2020年生醫感測器市場大突破元年," 環球生技月刊, 2017.
[2] A. Walcarius and E. Sibottier, "Electrochemically‐Induced Deposition of Amine‐Functionalized Silica Films on Gold Electrodes and Application to Cu (II) Detection in (Hydro) Alcoholic Medium," Electroanalysis: An International Journal Devoted to Fundamental and Practical Aspects of Electroanalysis, vol. 17, no. 19, pp. 1716-1726, 2005.
[3] X. Dai, O. Nekrassova, M. E. Hyde, and R. G. Compton, "Anodic stripping voltammetry of arsenic (III) using gold nanoparticle-modified electrodes," Analytical chemistry, vol. 76, no. 19, pp. 5924-5929, 2004.
[4] P. Mehrotra, "Biosensors and their applications – A review," Journal of Oral Biology and Craniofacial Research, vol. 6, no. 2, pp. 153-159, 2016.
[5] N. Verma and M. Singh, "Biosensors for heavy metals," Biometals, vol. 18, no. 2, pp. 121-129, 2005.
[6] C. Chen et al., "Recent advances in electrochemical glucose biosensors: a review," RSC Advances, vol. 3, no. 14, pp. 4473-4491, 2013.
[7] M. Baccarin, F. A. Santos, F. C. Vicentini, V. Zucolotto, B. C. Janegitz, and O. Fatibello-Filho, "Electrochemical sensor based on reduced graphene oxide/carbon black/chitosan composite for the simultaneous determination of dopamine and paracetamol concentrations in urine samples," Journal of Electroanalytical Chemistry, vol. 799, pp. 436-443, 2017.
[8] K. A. Giuliano and D. L. Taylor, "Fluorescent-protein biosensors: New tools for drug discovery," Trends in Biotechnology, vol. 16, no. 3, pp. 135-140, 1998.
[9] G. Liu, X. Mao, J. A. Phillips, H. Xu, W. Tan, and L. Zeng, "Aptamer−Nanoparticle Strip Biosensor for Sensitive Detection of Cancer Cells," Analytical Chemistry, vol. 81, no. 24, pp. 10013-10018, 2009.
[10] M. Sajid, M. K. Nazal, M. Mansha, A. Alsharaa, S. M. S. Jillani, and C. Basheer, "Chemically modified electrodes for electrochemical detection of dopamine in the presence of uric acid and ascorbic acid: a review," TrAC Trends in Analytical Chemistry, vol. 76, pp. 15-29, 2016.
[11] K.-Q. Deng, J.-h. Zhou, and X.-F. Li, "Direct electrochemical reduction of graphene oxide and its application to determination of L-tryptophan and L-tyrosine," Colloids and Surfaces B: Biointerfaces, vol. 101, pp. 183-188, 2013.
[12] P. Parkhey and S. V. Mohan, "Chapter 6.1 - Biosensing Applications of Microbial Fuel Cell: Approach Toward Miniaturization," in Microbial Electrochemical Technology, S. V. Mohan, S. Varjani, and A. Pandey Eds.: Elsevier, 2019, pp. 977-997.
[13] M. Cremer, "Über die Ursache der elektromotorischen Eigenschaften der Gewebe, zugleich ein Beitrag zur Lehre von polyphasischen Elektrolytke," R. Oldenbourg 1906.
[14] W. R. Heineman and W. B. Jensen, "Leland C. Clark Jr. (1918–2005)," Biosensors and Bioelectronics, vol. 21, no. 8, pp. 1403-1404, 2006.
[15] 許耀維、許梅娟, "生醫微檢測晶片," 化工技術, vol. Vol. 21, pp. 138-161, 2013.
[16] Brian Eggins, Biosensors an introduction, . John Wiley & son, 1996.
[17] R. Wilson and A. P. F. Turner, "Glucose oxidase: an ideal enzyme," Biosensors and Bioelectronics, vol. 7, no. 3, pp. 165-185, 1992.
[18] G. R. Marchesini, E. Meulenberg, W. Haasnoot, and H. Irth, "Biosensor immunoassays for the detection of bisphenol A," Analytica Chimica Acta, vol. 528, no. 1, pp. 37-45, 2005.
[19] J. Wang, "Electrochemical nucleic acid biosensors," Analytica Chimica Acta, vol. 469, no. 1, pp. 63-71, 2002.
[20] D. C. Wijesuriya and G. A. Rechnitz, "Biosensors based on plant and animal tissues," Biosensors and Bioelectronics, vol. 8, no. 3, pp. 155-160, 1993.
[21] P. Si, Y. Huang, T. Wang, and J. Ma, "Nanomaterials for electrochemical non-enzymatic glucose biosensors," RSC advances, vol. 3, no. 11, pp. 3487-3502, 2013.
[22] F. Scheller F. Schubert, Biosensors. Elsevier Science, 1991.
[23] R. S. Sethi, "Transducer aspects of biosensors," Biosensors and Bioelectronics, vol. 9, no. 3, pp. 243-264, 1994.
[24] P. Sistani, L. Sofimaryo, Z. R. Masoudi, A. Sayad, R. Rahimzadeh, and B. Salehi, "A penicillin biosensor by using silver nanoparticles," Int. J. Electrochem. Sci, vol. 9, pp. 6201-6212, 2014.
[25] A. Azadbakht, A. R. Abbasi, Z. Derikvand, and Z. Karimi, "The electrochemical behavior of Au/AuNPs/PNA/ZnSe-QD/ACA electrode towards CySH oxidation," Nano-Micro Letters, vol. 7, no. 2, pp. 152-164, 2015.
[26] S. Dzyadevych and N. Jaffrezic-Renault, "Conductometric biosensors," in Biological Identification: Elsevier, 2014, pp. 153-193.
[27] C. Barnes, C. d'Silva, J. Jones, and T. Lewis, "The theory of operation of piezoelectric quartz crystal sensors for biochemical application," Sensors and Actuators A: Physical, vol. 31, no. 1-3, pp. 159-163, 1992.
[28] A. S. Yuwono and P. S. Lammers, "Odor pollution in the environment and the detection instrumentation," Agricultural Engineering International: CIGR Journal, 2004.
[29] H. Sun and Y. Fung, "Piezoelectric quartz crystal sensor for rapid analysis of pirimicarb residues using molecularly imprinted polymers as recognition elements," Analytica chimica acta, vol. 576, no. 1, pp. 67-76, 2006.
[30] X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, "Sensitive optical biosensors for unlabeled targets: A review," analytica chimica acta, vol. 620, no. 1-2, pp. 8-26, 2008.
[31] 謝振傑, "光纖生物感測器," 物理雙月刊, vol. 廿四卷, no. 四期, 2006.
[32] C.-S. Lee, S. K. Kim, and M. Kim, "Ion-sensitive field-effect transistor for biological sensing," Sensors, vol. 9, no. 9, pp. 7111-7131, 2009.
[33] L. Rayleigh, "On waves propagated along the plane surface of an elastic solid," Proceedings of the London mathematical Society, vol. 1, no. 1, pp. 4-11, 1885.
[34] 黃仕泓、柯正浩, "表面聲波感測器之前瞻研究," 物理雙月刊, vol. 廿三卷, no. 六期, 2004.
[35] Y. Wang, Y. Li, L. Tang, J. Lu, and J. Li, "Application of graphene-modified electrode for selective detection of dopamine," Electrochemistry Communications, vol. 11, no. 4, pp. 889-892, 2009.
[36] T. Madrakian, E. Haghshenas, and A. Afkhami, "Simultaneous determination of tyrosine, acetaminophen and ascorbic acid using gold nanoparticles/multiwalled carbon nanotube/glassy carbon electrode by differential pulse voltammetric method," Sensors and Actuators B: Chemical, vol. 193, pp. 451-460, 2014.
[37] S. Hasoň, V. Ostatna, and M. Fojta, "Simultaneous voltammetric determination of free tryptophan, uric acid, xanthine and hypoxanthine in plasma and urine," Electrochimica Acta, vol. 329, p. 135132, 2020.
[38] J. Wang, "Electrochemical glucose biosensors," Chemical reviews, vol. 108, no. 2, pp. 814-825, 2008.
[39] J. Yu, L. Ge, J. Huang, S. Wang, and S. Ge, "Microfluidic paper-based chemiluminescence biosensor for simultaneous determination of glucose and uric acid," Lab on a Chip, vol. 11, no. 7, pp. 1286-1291, 2011.
[40] W. Li et al., "Pyridine functionalized carbon dots for specific detection of tryptophan in human serum samples and living cells," Microchemical Journal, vol. 154, p. 104579, 2020.
[41] J. Li et al., "Electrochemical tyrosine sensor based on a glassy carbon electrode modified with a nanohybrid made from graphene oxide and multiwalled carbon nanotubes," Microchimica Acta, vol. 180, no. 1-2, pp. 49-58, 2013.
[42] H. Beitollahi and F. Garkani Nejad, "Graphene oxide/ZnO nano composite for sensitive and selective electrochemical sensing of levodopa and tyrosine using modified graphite screen printed electrode," Electroanalysis, vol. 28, no. 9, pp. 2237-2244, 2016.
[43] Q. Xu and S.-F. Wang, "Electrocatalytic oxidation and direct determination of L-tyrosine by square wave voltammetry at multi-wall carbon nanotubes modified glassy carbon electrodes," Microchimica Acta, vol. 151, no. 1-2, pp. 47-52, 2005.
[44] N. Baig and A.-N. Kawde, "A novel, fast and cost effective graphene-modified graphite pencil electrode for trace quantification of l-tyrosine," Analytical Methods, vol. 7, no. 22, pp. 9535-9541, 2015.
[45] M. Arvand and T. M. Gholizadeh, "Simultaneous voltammetric determination of tyrosine and paracetamol using a carbon nanotube-graphene nanosheet nanocomposite modified electrode in human blood serum and pharmaceuticals," Colloids and Surfaces B: Biointerfaces, vol. 103, pp. 84-93, 2013.
[46] F. Tian, H. Li, M. Li, C. Li, Y. Lei, and B. Yang, "A tantalum electrode coated with graphene nanowalls for simultaneous voltammetric determination of dopamine, uric acid, L-tyrosine, and hydrochlorothiazide," Microchimica Acta, vol. 184, no. 6, pp. 1611-1619, 2017.
[47] F. Maggi and E. Daly, "Decomposition pathways and rates of human urine in soils," Journal of agricultural and food chemistry, vol. 61, no. 26, pp. 6175-6186, 2013.
[48] B. K. Swamy et al., "Simultaneous detection of dopamine, tyrosine and ascorbic acid using NiO/graphene modified graphite electrode," (in English), Biointerface Res. Appl. Chem., Article vol. 10, no. 3, pp. 5599-5609, Jun 2020, doi: 10.33263/briac103.599609.
[49] R. P. da Silva, A. W. O. Lima, and S. H. Serrano, "Simultaneous voltammetric detection of ascorbic acid, dopamine and uric acid using a pyrolytic graphite electrode modified into dopamine solution," Analytica chimica acta, vol. 612, no. 1, pp. 89-98, 2008.
[50] N. M. Felitsyn, G. N. Henderson, M. O. James, and P. W. Stacpoole, "Liquid chromatography–tandem mass spectrometry method for the simultaneous determination of δ-ALA, tyrosine and creatinine in biological fluids," Clinica Chimica Acta, vol. 350, no. 1-2, pp. 219-230, 2004.
[51] M. S. Alonso, L. L. Zamora, and J. M. Calatayud, "Determination of tyrosine through a FIA-direct chemiluminescence procedure," Talanta, vol. 60, no. 2-3, pp. 369-376, 2003.
[52] M. Lee, H. Nohta, Y. Umegae, and Y. Ohkura, "Assay for tyrosine hydroxylase by high-performance liquid chromatography with fluorescence detection," Journal of Chromatography B: Biomedical Sciences and Applications, vol. 415, pp. 289-296, 1987.
[53] G. Neurauter et al., "Simultaneous measurement of phenylalanine and tyrosine by high performance liquid chromatography (HPLC) with fluorescence detection," Clinical Biochemistry, vol. 46, no. 18, pp. 1848-1851, 2013.
[54] C. Bayle, N. Siri, V. Poinsot, M. Treilhou, E. Caussé, and F. Couderc, "Analysis of tryptophan and tyrosine in cerebrospinal fluid by capillary electrophoresis and “ball lens” UV-pulsed laser-induced fluorescence detection," Journal of Chromatography A, vol. 1013, no. 1-2, pp. 123-130, 2003.
[55] Y. Huang, X. Jiang, W. Wang, J. Duan, and G. Chen, "Separation and determination of l-tyrosine and its metabolites by capillary zone electrophoresis with a wall-jet amperometric detection," Talanta, vol. 70, no. 5, pp. 1157-1163, 2006.
[56] G. J. Trachte, T. Uncini, and M. Hinz, "Both stimulatory and inhibitory effects of dietary 5-hydroxytryptophan and tyrosine are found on urinary excretion of serotonin and dopamine in a large human population," Neuropsychiatric Disease and Treatment, vol. 5, p. 227, 2009.
[57] NIDA., "Drugs and the Brain," National Institute on Drug Abuse, , 2020. [Online]. Available: https://www.drugabuse.gov/publications/drugs-brains-behavior-science-addiction/drugs-brain.
[58] D. Amin, "Titrimetric determination of catecholamines and related compounds via bromine oxidation and substitution," Analyst, vol. 111, no. 2, pp. 255-257, 1986.
[59] Y. Lin, C. Chen, C. Wang, F. Pu, J. Ren, and X. Qu, "Silver nanoprobe for sensitive and selective colorimetric detection of dopamine via robust Ag–catechol interaction," Chemical Communications, vol. 47, no. 4, pp. 1181-1183, 2011.
[60] V. Carrera, E. Sabater, E. Vilanova, and M. A. Sogorb, "A simple and rapid HPLC–MS method for the simultaneous determination of epinephrine, norepinephrine, dopamine and 5-hydroxytryptamine: Application to the secretion of bovine chromaffin cell cultures," Journal of Chromatography B, vol. 847, no. 2, pp. 88-94, 2007.
[61] S. M. Ghoreishi, M. Behpour, M. Mortazavi, and A. Khoobi, "Fabrication of a graphene oxide nano-sheet modified electrode for determination of dopamine in the presence of tyrosine: a multivariate optimization strategy," Journal of Molecular Liquids, vol. 215, pp. 31-38, 2016.
[62] A. J. Bard and L. R. Faulkner, "Fundamentals and Applications, New York: Wiley, 2001," ed: Springer, 2002.
[63] 胡啟章, 電化學原理與方法. 五南圖書出版股份有限公司, 2002.
[64] W. Zhang et al., "An electrochemical sensor for detecting triglyceride based on biomimetic polydopamine and gold nanocomposite," Journal of Materials Chemistry B, vol. 2, no. 48, pp. 8490-8495, 2014.
[65] P. Electrochemistry, "Methods, and Applications, edited by CMA Brett and AMO Brett," ed: Oxford University Press, New York, 1993.
[66] Z.-G. Liu and X.-J. Huang, "Voltammetric determination of inorganic arsenic," TrAC Trends in Analytical Chemistry, vol. 60, pp. 25-35, 2014.
[67] M. C. Sousa and J. W. Buchanan, "Observational models of graphite pencil materials," in Computer Graphics Forum, 2000, vol. 19, no. 1: Wiley Online Library, pp. 27-49.
[68] Á. Torrinha, C. G. Amorim, M. C. B. S. M. Montenegro, and A. N. Araújo, "Biosensing based on pencil graphite electrodes," Talanta, vol. 190, pp. 235-247, 2018.
[69] S. Devaramani, M. Sreeramareddygari, M. R. Reddy, and R. Thippeswamy, "Covalently Anchored p‐Aminobenzene Sulfonate Multilayer on a Graphite Pencil Lead Electrode: A Highly Selective Electrochemical Sensor for Dopamine," Electroanalysis, vol. 29, no. 5, pp. 1410-1417, 2017.
[70] H. T. Purushothama, Y. A. Nayaka, M. M. Vinay, P. Manjunatha, R. O. Yathisha, and K. V. Basavarajappa, "Pencil graphite electrode as an electrochemical sensor for the voltammetric determination of chlorpromazine," Journal of Science: Advanced Materials and Devices, vol. 3, no. 2, pp. 161-166, 2018.
[71] B. B. Prasad, R. Madhuri, M. P. Tiwari, and P. S. Sharma, "Electrochemical sensor for folic acid based on a hyperbranched molecularly imprinted polymer-immobilized sol–gel-modified pencil graphite electrode," Sensors and Actuators B: Chemical, vol. 146, no. 1, pp. 321-330, 2010.
[72] P. K. Duy, J.-R. Sohn, and H. Chung, "A mechanical pencil lead-supported carbon nanotube/Au nanodendrite structure as an electrochemical sensor for As (III) detection," Analyst, vol. 141, no. 20, pp. 5879-5885, 2016.
[73] Á. Torrinha, C. G. Amorim, M. C. Montenegro, and A. N. Araújo, "Biosensing based on pencil graphite electrodes," Talanta, vol. 190, pp. 235-247, 2018.
[74] J. K. Kariuki, "An electrochemical and spectroscopic characterization of pencil graphite electrodes," Journal of the Electrochemical Society, vol. 159, no. 9, p. H747, 2012.
[75] P. Masawat, S. Liawruangrath, Y. Vaneesorn, and B. Liawruangrath, "Design and fabrication of a low-cost flow-through cell for the determination of acetaminophen in pharmaceutical formulations by flow injection cyclic voltammetry," Talanta, vol. 58, no. 6, pp. 1221-1234, 2002.
[76] S. Buratti, M. Scampicchio, G. Giovanelli, and S. Mannino, "A low-cost and low-tech electrochemical flow system for the evaluation of total phenolic content and antioxidant power of tea infusions," Talanta, vol. 75, no. 1, pp. 312-316, 2008.
[77] V. N. Popov, "Carbon nanotubes: properties and application," Materials Science and Engineering: R: Reports, vol. 43, no. 3, pp. 61-102, 2004.
[78] 李明洋、唐九君, "石墨烯的量子霍爾效應與弱局域效應," 物理雙月刊, vol. 33卷, no. 2, 2011.
[79] K. S. Novoselov et al., "Electric Field Effect in Atomically Thin Carbon Films," Science, vol. 306, no. 5696, p. 666, 2004. [Online]. Available:
.
[80] 陳韋任、沈銘原, "含奈米管之碳/碳複合材料之機械性質影響," 中華民國尖端材料科技協會, vol. 52期.
[81] 王鼎翔、呂明生、張守一, "先進奈米複合碳材料之未來發展與應用趨勢," 材料世界網, 2016.
[82] 蘇清源, "石墨烯氧化物之特性與應用前景," 物理雙月刊, vol. 33卷, no. 2期, 2011.
[83] W. S. Hummers and R. E. Offeman, "Preparation of Graphitic Oxide," Journal of the American Chemical Society, vol. 80, no. 6, pp. 1339-1339, 1958.
[84] Y. Li, J. Du, J. Yang, D. Liu, and X. Lu, "Electrocatalytic detection of dopamine in the presence of ascorbic acid and uric acid using single-walled carbon nanotubes modified electrode," Colloids and Surfaces B: Biointerfaces, vol. 97, pp. 32-36, 2012.
[85] J. Huang, Y. Liu, H. Hou, and T. You, "Simultaneous electrochemical determination of dopamine, uric acid and ascorbic acid using palladium nanoparticle-loaded carbon nanofibers modified electrode," Biosensors and Bioelectronics, vol. 24, no. 4, pp. 632-637, 2008.
[86] W. Zhu, T. Chen, X. Ma, H. Ma, and S. Chen, "Highly sensitive and selective detection of dopamine based on hollow gold nanoparticles-graphene nanocomposite modified electrode," Colloids and Surfaces B: Biointerfaces, vol. 111, pp. 321-326, 2013.
[87] A. El‐Beqqali, A. Kussak, and M. Abdel‐Rehim, "Determination of dopamine and serotonin in human urine samples utilizing microextraction online with liquid chromatography/electrospray tandem mass spectrometry," Journal of separation science, vol. 30, no. 3, pp. 421-424, 2007.
[88] 詹雅云, "中空含氮碳材修飾電極應用於同時偵測抗壞血酸、多巴胺及尿酸之研究," 國立成功大學化學工程學系碩士論文, 2015.
[89] L. J. Hardwick et al., "An in situ Raman study of the intercalation of supercapacitor-type electrolyte into microcrystalline graphite," Electrochimica Acta, vol. 52, no. 2, pp. 675-680, 2006.
[90] M. S. Dresselhaus and G. Dresselhaus, "Intercalation compounds of graphite," Advances in physics, vol. 51, no. 1, pp. 1-186, 2002.
[91] Z. Y. Xia et al., "The exfoliation of graphene in liquids by electrochemical, chemical, and sonication‐assisted techniques: A nanoscale study," Advanced Functional Materials, vol. 23, no. 37, pp. 4684-4693, 2013.
[92] A. Özcan and Y. Şahin, "Selective and sensitive voltammetric determination of dopamine in blood by electrochemically treated pencil graphite electrodes," Electroanalysis, vol. 21, no. 21, pp. 2363-2370, 2009.
[93] R. C. Engstrom, "Electrochemical pretreatment of glassy carbon electrodes," Analytical Chemistry, vol. 54, no. 13, pp. 2310-2314, 1982.