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Đề tài : Nghiên cứu chế tạo cảm biến nano sinh học để chuẩn đoán và định lượng một số hợp chất sinh học

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Đề tài : Nghiên cứu chế tạo cảm biến nano sinh học để chuẩn đoán và định lượng một số hợp chất sinh học thuộc công trình nghiên cứu khoa học cấp bộ . Nội dung gồm

B KHOA H C VÀ CƠNG NGH PHỊNG THÍ NGHI M CÔNG NGH NANO ð I H C QU C GIA TP H CHÍ MINH ð TÀI KHOA H C CÔNG NGH C P NHÀ NƯ C NGHIÊN C U KHOA H C VÀ PHÁT TRI N CÔNG NGH BÁO CÁO T NG H P K T QU KHOA H C CÔNG NGH ð TÀI NGHIÊN C U CH T O C M BI N NANO SINH H C ð CH N ðOÁN VÀ ð NH LƯ NG M T S H P CH T SINH H C Mã s : KC.04.12/06-10 Cơ quan ch trì đ tài: Phịng Thí Nghi m Cơng Ngh Nano Ch nhi m đ tài: TS T ng Duy Hi n TP H Chí Minh, 10 - 2010 B KHOA H C VÀ CÔNG NGH ð I H C QU C GIA TP H CHÍ MINH ð TÀI KHOA H C CÔNG NGH C P NHÀ NƯ C NGHIÊN C U KHOA H C VÀ PHÁT TRI N CÔNG NGH BÁO CÁO T NG H P K T QU KHOA H C CÔNG NGH ð TÀI NGHIÊN C U CH T O C M BI N NANO SINH H C ð CH N ðOÁN VÀ ð NH LƯ NG M T S H P CH T SINH H C Mã s : KC.04.12/06-10 Ch nhi m đ tài: Cơ quan ch trì đ tài: TS T ng Duy Hi n PGS.TS ð ng M u Chi n Ban ch nhi m chương trình (ký tên) B Khoa h c Cơng ngh Văn Phịng Chương Trình (ký tên đóng d u g i lưu tr ) TP H Chí Minh, 11 - 2010 L I C M ƠN Trước tiên xin chân thành cảm ơn Bộ Khoa học Công nghệ hỗ trợ cấp kinh phí thực đề tài Nhóm nghiên cứu xin chân thành ghi nhận đóng góp hữu hiệu đối tác nước nước ngoài: - Viện Sinh học Nhiệt đới – Viên Khoa học Công nghệ Việt nam, Đại học Y Dược TP HCM, Viện Vệ sinh Dịch tễ Trung Ương Viện Nghiên cứu Công nghệ Nano, ĐH Tổng hợp Twente, Hà lan, Và mong muốn tiếp tục cộng tác tương lai Chúng xin chân thành cảm ơn: - Văn Phịng Các Chương Trình, Chương Trình KC04/06-10, Ban Giám đốc ĐHQG Tp Hồ Chí Minh, Ban KHoa học Cơng nghệ, ĐHQG Tp Hồ Chí Minh, Phịng Thí nghiệm Cơng nghệ Nano Và cộng sự, Đã đạo, tạo điều kiện thuận lợi, động viên khích lệ chúng tơi hồn thành đề tài TP Hồ Chí Minh, tháng 10-2010 Chủ nhiệm đề tài TS Tống Duy Hiển ð I H C QU C GIA TP.HCM C NG HOÀ XÃ H I CH NGHĨA VI T NAM PHỊNG THÍ NGHI M CƠNG NGH NANO ð c l p - T - H nh phúc TP HCM, ngày tháng năm 2010 BÁO CÁO TH NG KÊ K T QU TH C HI N ð TÀI I THÔNG TIN CHUNG Tên ñ tài: Nghiên c u ch t o c m bi n nano sinh h c đ ch n đốn ñ nh lư ng m t s h p ch t sinh h c Mã s ñ tài: KC04.12/06-10 Thu c: - Chương trình cơng ngh sinh h c (lĩnh v c KHCN): K thu t công ngh Tên ch nhi m: H tên: T ng Duy Hi n Ngày, tháng, năm sinh: 30/ 01/ 1973 Nam/ N : Nam H c hàm, h c v : Ti n s Ch c danh khoa h c: Nghiên c u viên; ch c v : Phó Giám ñ c ði n tho i: T ch c: 84-8-37242160 - Ext 4632; Nhà riêng: 84-4-6271780 Mobile: 01272656907 Fax: 84-8-37242163 E-mail: tdhien@vnuhcm.edu.vn, tongduyhien2001@yahoo.com Tên t ch c cơng tác: Phịng Thí Nghi m Cơng Ngh Nano (LNT) - ð i H c Qu c Gia TP H Chí Minh ð a ch t ch c: Khu Ph 6, Phư ng Linh Trung, Qu n Th ð c, TP H Chí Minh ð a ch nhà riêng: 24/495 B ch Mai, Thành ph Hà N i Tên t ch c ch trì: Tên t ch c ch trì đ tài: Phịng Thí Nghi m Cơng Ngh Nano (LNT) ði n tho i: 84-8-37242160 - Ext 4612/4613 Fax: 84-8-37242163 E-mail: lnt@vnuhcm.edu.vn i Website: www.hcmlnt.edu.vn ð a ch : Khu Ph 6, Phư ng Linh Trung, Qu n Th ð c, TP H H tên th trư ng t ch c: PGS.TS ð ng M u Chi n S tài kho n: 931.01.00.00100 Ngân hàng: Kho B c Nhà Nư c TP H Chí Minh Tên quan ch qu n đ tài: B Khoa h c Cơng Ngh II TÌNH HÌNH TH C HI N Th i gian th c hi n ñ tài: - Theo H p ñ ng ñã ký k t: t tháng 03 năm 2008 ñ n tháng 10 năm 2010 - Th c t th c hi n: t tháng 09 năm 2008 đ n tháng 11 năm 2010 Kinh phí s d ng kinh phí: a) T ng s kinh phí th c hi n: 3.950 tri u đ ng, đó: + Kính phí h tr t SNKH: 3.950 tri u đ ng + Kinh phí t ngu n khác: b) Tình hình c p s d ng kinh phí t ngu n SNKH: S TT Theo k ho ch Ghi Th c t ñ t đư c (S đ ngh quy t tốn) Th i gian Kinh phí (Tr.đ) Th i gian Kinh phí (Tr.ñ) 2008 1.300 2008 943.7 770 2009 1.882 2009 2054.8 1209.5 2010 768 2010 951.5 1970.5 3.950 C ng 3.950 3.950 C ng c) K t qu s d ng kinh phí theo kho n chi: ðơn v tính: Tri u đ ng Theo k ho ch Th c t ñ t ñư c S TT N i dung kho n chi T ng SNKH Ngu n khác T ng SNKH Tr công lao ñ ng (khoa h c, ph 1.250 1.250 1.250 1.250 - Ngu n khác ii thông) Nguyên, v t li u, lư ng 1.200 1.200 - 1.190,040544 1.190,040544 Thi t b , máy móc 1.120 1.120 - 1.108,920 1.108,920 Xây d ng, s a ch a nh - - - - - Chi khác 380 380 - 391,251375 391,251375 3.950 3.950 - 3.940,211919 3.940,211919 T ng c ng Các văn b n hành q trình th c hi n đ tài: (Li t kê quy t ñ nh, văn b n c a quan qu n lý t cơng đo n xác ñ nh nhi m v , xét ch n, phê t kinh phí, h p đ ng, ñi u ch nh (th i gian, n i dung, kinh phí th c hi n n u có); văn b n c a t ch c ch trì ñ tài, d án (ñơn, ki n ngh ñi u ch nh n u có) S S , th i gian ban hành Tên văn b n TT văn b n Quy t ñ nh s 293/Qð- - V vi c phê t kinh phí đ tài BKHCN ngày c p Nhà nư c b t ñ u th c hi n 29/02/2008 năm 2008 thu c chương trình “ Nghiên c u, phát tri n ng d ng Công ngh sinh h c”, mã s KC04.12/06-10 H p ñ ng s - H p ñ ng Nghiên C u Khoa H c 12/2008/Hð-ðTCTvà phát tri n cơng ngh KC.04.12/06-10 Quy t đ nh s - V vi c thay ch nhi m ñ tài 2001/Qð-BKHCN ngày KC.04.12/06-10 thu c chương trình 15/09/2008 “Nghiên c u, phát tri n ng d ng công ngh sinh h c” mã s KC.04.12/06-10 Quy t ñ nh s -V vi c phê t K ho ch ñ u 2024/Qð-BKHCN ngày th u mua s m tài s n c a ñ tài 16/09/2008 thu c chương trình “Nghiên c u, phát tri n ng d ng công ngh sinh h c” mã s KC.04.12/06-10 Quy t ñ nh s 105/Qð- - V vi c phê t k t qu ñ u ðHQG-PTNCNNN th u gói th u cung c p, l p ñ t “ ngày 27/10/2008 Thi t b ki m tra tính ch t n đ c trưng c a c m bi n” Quy t ñ nh s 370/Qð- -V vi c phê t K ho ch ñ u Ghi iii BKHCN 19/03/2009 ngày th u mua s m tài s n c a ñ tài thu c chương trình “Nghiên c u, phát tri n ng d ng công ngh sinh h c” mã s KC.04.12/06-10 Quy t ñ nh s 105/Qð- - V vi c phê t k t qu ñ u ðHQG-PTNCNNN th u gói th u “ Hóa ch t ph c v ngày 27/10/2008 nghiên c u” “ V t tư ph c v nghiên c u” thu c ñ tài NCKH c p Nhà nư c Quy t ñ nh s 347/Qð- - V vi c c đồn cơng tác nư c BKHCN ngày ngồi 169/03/2009 Quy t đ nh s 416/Qð- - V vi c c cán b viên ch c ñi ðHQG-TCCB cơng tác t i nư c ngồi Quy t đ nh s 81/Qð- -V vi c phê t K ho ch ñ u BKHCN ngày th u mua s m tài s n c a ñ tài 22/01/2010 thu c chương trình “Nghiên c u, phát tri n ng d ng công ngh sinh h c” mã s KC.04.12/06-10 Quy t ñ nh s 12/ Qð- - V vi c phê t k t qu ñ u ðHQG-PTNCNNN th u gói th u “ Nguyên v t li u ngày 27/10/2008 ph c v nghiên c u” thu c ñ tài NCKH c p Nhà nư c 10 11 T ch c ph i h p th c hi n ñ tài: S TT Tên t ch c ñăng ký theo Thuy t minh Phịng Thí Nghi m Cơng Ngh Nano ðHQG TP HCM Tên t ch c N i dung ñã tham gia tham gia th c hi n ch y u Phịng Thí Nghiên c u Nghi m Công Ngh Nano ðHQG TP HCM Vi n Sinh h c Nhi t ñ i Vi n Khoa h c Cơng Vi n Sinh h c Nhi t đ i - Vi n Khoa h c S n ph m ch y u Ghi ñ t ñư c chú* - B c m bi n glucose v i h đo 100 chip hồn ch nh v i th i gian ño 30-60s - 100 chip s i nano silic dùng ñ phát hi n DNA lai Ph i h p - C cán b ph i nghiên c u h p nghiên c u th nghi m c m bi n s i nano iv ngh Nam Vi t Công ngh Vi t Nam platin ñ nh lư ng glucose h p - Cung c p m u ð i h c Y ð i h c Y Ph i b nh nhân ti u Dư c TP Dư c TP nghiên c u ñư ng HCM HCM ng d ng - B ng ñánh giá Khoa N i Ti t Vi n v sinh qu chip Silicon Nano- B nh vi n d ch t trung k t ương nghiên c u wire (SNW) dùng Ch R y TP ñ phát hi n DNA HCM ngo i l i (LNT SiNW) Cty TNHH ng d ng - B ng ñánh giá b Thi t b k t qu c m bi n nano sinh KHKT Nam nghiên c u h c v i c u trúc Phát chip s i nano platin dùng ñ ñ nh lư ng glucose máu - Lý thay đ i (n u có): Hai đ i tác m i có chun mơn, nhu c u ng d ng phù h p v i s n ph m c a ñ tài nghiên c u Cá nhân tham gia th c hi n ñ tài: (Ngư i tham gia th c hi n ñ tài thu c t ch c ch trì quan ph i h p, không 10 ngư i k c ch nhi m) S TT Tên cá nhân ñăng ký theo Thuy t minh Tên cá nhân ñã tham gia th c hi n TS T ng Nghiên c u viên Duy Hi n Phịng Thí Nghi m Công Ngh Nano ðHQG TP HCM PGS ð ng S n ph m N i dung tham gia ch y u đ t đư c Ghi * Ch nhi m ñ tài, ñ nh hư ng nghiên c u, ñánh giá k t qu nghiên c u Ch u trách nhi m chuyên môn v công ngh ch t o s i nano kim lo i, bán d n c m bi n nano sinh h c TS Giám đ c Phịng Thí ð nh hư ng nghiên c u, M u Nghi m Công Ngh tư v n chuyên môn v v Chi n Nano - ðHQG TP công ngh ch t o s i HCM nano vi linh ki n PGS TS Ch nhi m B môn BS Nguy n N i ti t - Trư ng Thy Khuê ð i h c Y Dư c TP HCM Tư v n chun mơn v quy trình ng d ng c m bi n nano sinh h c ñ ñ nh lư ng n ng ñ glucose máu PGS TS Trư ng Phòng Nguy n Nghiên c u Vi n Ti n Th ng Sinh h c Nhi t ñ i Vi n KHCN Vi t Nam Tư v n chun mơn v quy trình ng d ng c m bi n nano sinh h c ñ ch n ñoán ñ nh lư ng m t s protein, ADN ngo i lai ThS ðoàn Nghiên c u viên ð c Chánh Phịng Thí Nghi m Tín Cơng Ngh Nano ðHQG TP HCM Thi t k , ch t o c m bi n nano sinh h c d a c u trúc s i nano bán d n đ ch n đốn đ nh lư ng m t s protein, ADN ngo i lai ðánh giá t i ưu hóa thơng s ch t o Thi t k , ch t o ph n c ng ph n m m ph tr ñ t o thành h c m bi n hoàn ch nh ThS ð ng Nghiên c u viên Ng c Thùy Phịng Thí Nghi m Dương Cơng Ngh Nano ðHQG TP HCM Th nghi m c m bi n nano sinh h c d a c u trúc s i nano bán d n: g n k t, th đ ng hóa m i b t c p thích h p cho q trình đ nh lư ng protein ADN lên s i nano ThS Nguy n Thành Chi n Nghiên c u viên Phịng Thí Nghi m Cơng Ngh Nano ðHQG TP HCM Thi t k , ch t o c m bi n nano sinh h c d a c u trúc s i nano kim lo i ñ ñ nh lư ng n ng ñ glucose máu vi Ths Tr n Nghiên c u viên Nhân Ái Phịng Thí Nghi m Cơng Ngh Nano ðHQG TP HCM Thi t k , ch t o c m bi n nano sinh h c d a c u trúc s i nano kim lo i ñ ñ nh lư ng n ng ñ glucose máu ðánh giá t i ưu hóa thơng s ch t o KS Lê Th Thanh Tuy n Nghiên c u viên Phịng Thí Nghi m Cơng Ngh Nano ðHQG TP HCM Th nghi m c m bi n nano sinh h c d a c u trúc s i nano kim lo i: G n k t, th đ ng hóa enzym thích h p cho q trình đ nh lư ng glucose lên s i nano platin 10 Ths Ph m Nghiên c u viên Văn Bình Phịng Thí Nghi m Cơng Ngh Nano ðHQG TP HCM Th nghi m c m bi n nano sinh h c d a c u trúc s i nano bán d n: g n k t, th ñ ng hóa m i b t c p thích h p cho q trình đ nh lư ng protein ADN lên s i nano 11 TS Mai Trư ng nhóm sensor Th nghi m c m bi n Anh Tu n sinh h c, Vi n Qu c nano sinh h c d a T ðào T o v Khoa c u trúc s i nano silic H c V t Li u, ðHBK Hà n i 12 Ths Tr n Vi n V Sinh D ch Th nghi m c m bi n Quang Huy T Trung Ương nano sinh h c d a c u trúc s i nano silic s i nano Pt cho phân tích sinh h c khác - Lý thay đ i (n u có): M t s cán b chuy n cơng tác đư c thay th b ng CB nghiên c u khác có chun mơn phù h p Tình hình h p tác qu c t : vii 50 Tran Nhan Ai, Le Thi Thanh Tuyen, Dang Le Khoa, Tong Duy Hien, and Dang Mau Chien CONCLUSION In this paper, we have investigated platinum thin layer fabricated by sputtering for glucose sensing The calibration curves strongly suggested that sputtered platinum electrode can be used as glucose sensors with the detection range from mM to 16 mM The sensitivities of such sensors improved with the increase in electrode surface roughness factor The imobilization of enzyme onto the electrode surface would be strengtened by the use of a polymer membrane consist of chitosan and glutaraldehyde Glucose sensors based on sputtered electrodes are easy to fabricate, highly sensitivity and are suitable for mass production ACKNOWLEDGMENTS We appreciate Laboratory for Nanotechnology, Vietnam National University, Ho Chi Minh City and Electrochemistry Laboratory, University of Natural Sciences, Ho Chi Minh City for their sponsorship and support REFERENCES J Zhu, Z Zhu, Z Lai, R Wang, X Guo, X Wu, G Zhang, Z Zhang, Y Wang, and Z Chen, Sensors 2, 127 (2002) M Yang, Y Yang, B Liu, G Shen, and R Yu, Sensor Actuat B 101, 269 (2004) Y Lin, F Lu, Y Tu, and Z Ren, Nano Letters 4, 191 (2004) S Yao, J Xu, Y Wang, X Chen, Y Xu, and S Hu, Anal Chim Acta 557, 78 (2006) M Yang, F Qu, Y Lu, Y He, G Shen, and R Yu, Biomaterials 27, 5944 (2006) J Wang, N.V Myung, M Yun, and H.G Monbouquette, J Electroanal Chem 575, 139 (2005) S Park, H Boo, and T.D Chung, Anal Chim Acta 556, 46 (2006) M.F.L de Mele, H.A Videla, and A.J Arvla, J Electrochem Soc 129, 2207 (1982) D.R Lide, CRC Handbook of Chemistry and Physics, Taylor & Francis, Boca Raton, Florida, 2007 10 D Wang, R Kou, M.P Gil, H.P Jakobson, J Tang, D Yu, and Y Lu, J Nanosci Nanotech 5, 1904 (2005) Corresponding author: Tran Nhan Ai, Laboratory for Nanotechnology, Vietnam National University, Ho Chi Minh City, Community 6, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam E-mail: tnai@vuhcm.edu.vn The 5th International Workshop on Advanced Materials Science and Nanotechnology (IWAMSN2010) - Hanoi, Vietnam - November 09-12, 2010 SELF-ASSEMBLED CYSTEAMINE ONTO PLATINUM NANOWIRE ARRAYS TO ENHANCE IMMOBILIZATION OF GLUCOSE OXIDASE ON PLATINUM NANOWIRES FOR DIRECT GLUCOSE DETECTION IN HUMAN BLOOD Duy Phu Tran 1, Hien Duy Tong 1,2, Tung Thanh Xuan Pham 1, Binh Van Pham 1, Chien Thang Nguyen1, Tuyen Thanh Le Thi 1, Chien Mau Dang 1 Laboratory for Nanotechnology, Vietnam National University Community 6, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam Email: tpduy@vnuhcm.edu.vn Nanosens Research B.V., Berkelkade 11, NL 7201 JE Zutphen, The Netherlands Abstract Self-assembly functional alkanthiols Cysteamine (CA) provides a simple but effective route to organize suitable organic molecules on platinum (Pt) nanowires and other selected nanocluster surfaces In our paper, CA monolayers is created on the surface of Pt nanowire via self-assembly technique for further immobilizing enzyme of glucose oxidase on Pt surface for sensitive detection of glucose The results show that the forming of CA monolayers on Pt nanowire surface drastically enhances the immobilization efficiency of the enzyme binding on Pt nanowire surface This is crucial factor to obtain sensitive and realizable nanobiosensors for determination of glucose concentrations in a human blood Finally, the developed nanowire sensors successfully and directly determine glucose concentrations in human blood samples for diagnosing of diabetics This is first but important step for complete development of nano-biosensors for monitoring of glucose level in blood Keywords: Self-assembly, Nano-biosensors, Glucose, Human blood INTRODUCTION Self-assembled monolayer (SAM) and its application has been attracted the attention of scientists in recent year That potential method is mostly used to modify noble metal by governing function organic chemical onto the metal surface for application in different area of science and technology such as: sensors, optical devices, electronic memory storage [1-4]…Especially, SAM is a crucial technique to create ultra-sensitive medical diagnostic apparatus [2-7] In this paper, we present the successful Cysteamine self-assembled monolayer on Pt surface at nano-scale The newly developed Cysteamine monolayer self-assembly on Pt surface and the GOx immobilization process were described in detail with these optimized conditions Then, the Cysteamine modified Pt nanowires were immobilized with Glucose Oxidase enzymes and were applied as nanowire nanosensors on Glucose detection in human blood EXPERIMENTAL 2.1 Reagents and apparatus Cysteamine hydrochcloride (CA) 99.5% (Sigma-USA), Potassium Ferricyanide (III) (K3FeCN6) 99+% (Sigma) and Glutaraldehyde 25% wt (Merck-Germany) were used as received Glucose Oxidase, E.C 1.1.3.4 type X-S, 250 KU from Asperillus niger and D-(+) Glucose 99.5% were purchased from Sigma Platinum nanowire arrays were fabricated and tested the electrical properties prior use Human Blood was purchased from Hospital of Hematology and Blood Transfusion, type O+, anti-blood clotting regents CPDA All other reagents were analytical grade and the different solutions were prepared with de-ion water Cyclic Voltammetry measurements were performed by using Potentiostat/Galvanostat Autolab PGSTAT302 N equipped with Nova 1.5 software (EcoChemie, Utrecht, The Netherlands) 2.2 Preparation of Pt nanowire arrays modified Cysteamine Pt nanowire chips having nanowires with width around 35 nm and lengths from several microns to tens of microns have been fabricated by using DEA technique The further information of appropriate processes for Pt nanowire arrays fabrication are reported elsewhere [8-9] Only Pt chips, which maintain the resistance under 10 KΩ (kOhms), were allowed for the further modification Then, Pt nanowires were polished deeply by soaking in the mixture of Ethanol 100% and Acetone in hour and continuously oxygenating any remained organic traces on the Pt surface by using Oxygen-Plasma apparatus in minutes Subsequently, the clean Pt chips were placed immediately into 0.5 M CA solution in darkness at 40C for 20 hours of forming CA monolayer For better measurement results, Pt modified chips were rinsed to remove the un-linked CA molecules prior further modification 2.3 Preparation of modified Pt nanowires on Glucose detection Immobilization of Glucose Oxidase onto functional Pt nanowire surface was performed in two steps processes Firstly, Pt-CA chips were functionalized by anchoring Glutaraldehyde (GAD) 25% wt in hours at the ambience condition After two hours of functionalizing GAD, modified chips also were rinsed with copious of water to remove any non-covalent binding GADs Then, these functionalized chips were immersed in Glucose Oxidase solution (5mg/ml; type X-S, 250KU; pH 7.0) in darkness at 40C for hours Finally, Pt nanowire arrays modified CA self-assembled monolayer were immobilized GOx through GAD linker was ready for the measurement Cycling Voltametric process was carried out with three electrodes system A platinum rod 0.5 mm diameter was used as a counter electrode while reference electrode was Ag/AgCl Immobilized Platinum chip was applied in the system as working electrode 2.4 Preparation Human Blood ready for Glucose quantitative analysis Human vein blood with low soluble Oxygenate concentration was diluted in Nitrogen saturated de-ion water pH 7.0 up to 10 times Afterward, diluted blood was added glucose solution with desired concentration and used without further modification The desired solution was arranged from 0.5 - – – – – 10 mM in glucose concentration The Ultra-Touch glucose meter (Life-scan, Johnson & Johnson) was applied to confirm the glucose concentration on each desired blood sample The three electrode system was soaked in the Potentiostat cell containing 15 ml of expected blood sample The scan rate of potential applied on all the measurement was 200 mV/s, measurement step was 2.4 mV in the range from -1 to +1 V RESULTS AND DISCUSSION Figure shows a high resolution scanning electron microscopy (HR: SEM) image of the fabricated Pt nanowire arrays (a) and single nanowire (b) Each array contain 100 nanowires which has a width of ca 32 ±5 nm and length up to 20 µm with strait and smooth surface quality The resistance of these chips approximately about 700 Ω (Ohms) The resistance was an important factor which would be discussed further on this paper Fig.1 High resolution scanning electron microscopy of fabricated nanowires arrays (a) and single nanowire (b) Formation of Cysteamine molecules on Pt nano surface are quite complicated due to the observation that thiols and disulfides with short carbon chains give rise to less well-organized monolayers compared to those having longer hydrocarbon chains [11-15] First of all, to build a good CA monolayer, it is essential to avoid any organic substances on the Pt surface by applying a deeply cleaning process The nonpolar solvent like acetone was used to dissolved any non-polar organic substances and the polar solution such as ethanol was applied to disolved the polar substances remain on the Pt surface To ensure that all of Pt surfaces was clean and clear, Oxygen Plasma apparatus was obtainted in minutes to oxigenate all of organic traces on the Pt Secondly, due to the native characteristics of our Pt nanowires are cluster of tiny nano Pt drains [8-10], so the contacting surface between Pt and the CA molecules would be lager than nano Pt thin film However, it doesn’t mean that the more exposed surface, the better creation CA monolayer [5-7] It likely to see that the conformation of CA monolayer was affected by the Pt surface structures, ionic amino group on CA , the interaction between monolayer and the solvent , pH solution and immersion time [13-15] Fig (a) Cyclic Voltamogram of various CA immersion time in K3FeCN6 0.25 M solution from top to bottom 0-5-10-20-30-40 hours at 200 mV.s-1 (b) calibration curve of current received Oxidation peak at +0.4V In the figure 2, the hours incompleted coat layer presented the higher current received oxidation peak at +0.4 V than the layer of 10 – 20 – 30 – 40 hours In our obsevation, the hours layer couldn’t cover the metal Pt surface as well as the longer time layer Moreover, over the approriate immersion time ( over 20 hours) the oxidation peak of K3FeCN6 was almost equal as other longer immersion time values In our experiment, the most aprroriate time for creation CA mono-organic layer on Pt nanowire arrays was 20 hours in the laboratory’s condition Thus, the most important thing is that we already demonstrated the presence of CA monolayer presented in that figure The Pt nanowire arrays modified Cysteamine monolayer process has been optimized and applied to Glucose detection is shown schematically in Figure In the enzyme immobilization procedure, the GAD molecules played a role of adhesive molecules, which hooked both Amino terminal groups of CA layer and enzyme Due to the nature of the GOx enzyme, particularly the Lysine amino acid and its nucleophiles reactive amino acid side-chains, reacted strongly with one of the functional Aldehyde group[12-15] while the other Aldehyde precursor was bound to the amino terminal group on CA monolayer Fig Cysteamine enhanced Pt chip for Glucose Oxisae enzyme immobilization and Glucose detetction The Glucose sensor based on GOx enzyme immobilization have a high selective and high sensitivity, life time, etc., are also reported recently [4-9] The detection of Glucose with an enzymes electrode based on the electrochemical detection of H2O2 When applied on Glucose detection, the immobilized GOD enzyme on this sensor catalyzes the oxidation of glucose to Gluconolactone, while coenzyme Favinadenindinucleotide (FAD) is reduced to FADH2 After that, the molecular oxygen functions as an electron acceptor for FADH2 and re-oxidized FADH2 to FAD, whereas O2 is reduced to hydrogen peroxide (H2O2) β-D-glucose + GOx (FAD) → Glucono-δ-lactone + GOx(FADH2) GOx(FADH2) + O2 → GOx(FAD) + H2O2 Glucono-δ-lactone + H2O2 → Gluconic acid β-D-glucose + O2 + H2O → Gluconic acid + H2O2 H2O2 → O2 + 2H+ + 2eThe H2O2 was then detected during the amperometric measurement This allows the determination of corresponding glucose concentration in the human blood The response current of immobilized Pt nanowires electrode for different concentration of Glucose (0.5 mM – 10 mM) in blood is shown in figure 4, respectively It was observed that the response current peak increased with increasing Glucose concentration in range of 0.5 – 10 mM at -0.72 V That result was a little different with the other authors whose Glucose Oxidation peak concentrated around +0.6 V [3-10] One of the major different that made the change in the Glucose Oxidation peak was the Platinum nanowire arrays’ structure In the fabrication procedure, due to the unattached between Platinum and the Silicon wafer surface, a nano-thin film Chromium (Cr) was applied as an adhesive layer between Si wafer and Platinum nanowires Therefore, the Pt nanowires were an alloy, which Cr was covered by Pt On the Glucose detection process, the rapid reaction of GOx with Glucose at a nano-scaled surface plus with the Pt-Cr nanowires can made a difference in Glucose oxidation peak We also didn’t find any differences in measurement resuls when observed the affect of endogenous and exogenous substances such as: ascorbic acid, uric acid, paracetamol with varous level in human blood to Glucose detection Most importantly, although there was a little different in Glucose oxidation peak position, we also observed the current response increase with high repetitive, sensitive and durability when increasing Glucose concentration That Oxidation peak current response on the electrochemical reaction exhibited the good linearity for sensing Glucose on the calibration curves of glucose detection with the correlation approximately 99 % (r =0.9938) Fig.4 (a) Cyclic voltammograms of immoblized Pt chips in human blood with diferent concentration From top to bottom 10 – 8- – 4- – 0.5 mM Glucose (b) Calibration plots for GOx biosensor: scan rate 200mV.s-1 vs Ag/AgCl reference electrode, potential range: -1 to +1 V Pt nanowire chips having nanowire array have been fabricated, then immobilized with GOx enzyme through CA self-assemble monolayer for subsequence oxidation and detection of glucose in solution By using the newly Cysteamine self-assembly monolayer technique, we have successfully integrated the biology signal transducer to the nanowires framework and concentrated our effort to develop Pt nanowire based biosensor for detection of glucose in blood ACKNOWLEDGEMENT We gratefully acknowledge the financial support of the National University – Ho Chi Minh City and Laboratory for Nanotechnology under grant KC.04.12/06-10 REFERENCES Z Nie, A Petukhova and E Kumacheva Nature Nanotechnology 5, 15 (2009) D Chen, Jinghong Li Surface Science Reports 61, 445–463 (2006) J J Gooding, D B Hibbert Trends in anal Chemis., vol 18, (1999) R K Shervedani, S A Mozaffari Surface & Coatings Technology 198, 123–128 (2005) R K Shervedani, A Farahbakhsh, M Bagherzadeh Anal.Chimi Acta 587, 254–262 (2007) R K Shervedani, A Hatefi-Mehrjardi Sensors and Actuators B 126, 415–423 (2007) J A Ho, L.Wu , N.Fan , M Lee, H Kuo, C Yang Talanta 71, 391–396 (2007) H.D Tong, E.T Carlen et al., Nanoletters, 9,1015 (2009) H D Tong, T.P Duy, T.T.T Le Adv Nat Sci Nanosci Nanotechnol 1, 015011(2010) 10 T T.X Pham, H D Tong, T.P Duy Adv Nat Sci Nanosci Nanotechnol 1, 025013 (2010) 11 R.Garjonyte, A.Malinauskas Biosen & Bioelec., 15,445 (2000) 12 Q.Chi, S.Dong Anal Chim Acta., 310, 429 (1995) 13 M.Wirde 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HI N ð TÀI I THƠNG TIN CHUNG Tên đ tài: Nghiên c u ch t o c m bi n nano sinh h c đ ch n đốn đ nh lư ng m t s h p ch t sinh h c Mã s ñ tài: KC04.12/06-10 Thu c: - Chương trình cơng ngh sinh h... thành cảm ơn Bộ Khoa học Công nghệ hỗ trợ cấp kinh phí thực đề tài Nhóm nghiên cứu xin chân thành ghi nhận đóng góp hữu hiệu đối tác nước nước ngoài: - Viện Sinh học Nhiệt đới – Viên Khoa học Công... (lĩnh v c KHCN ): K thu t công ngh Tên ch nhi m: H tên: T ng Duy Hi n Ngày, tháng, năm sinh: 30/ 01/ 1973 Nam/ N : Nam H c hàm, h c v : Ti n s Ch c danh khoa h c: Nghiên c u viên; ch c v : Phó Giám

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