Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352078
Toshio Fukudal, Pou Liu
Carbon nanotube (CNT) can be used as a building block of nanoelectronic mechanical systems (NEMS). The main problems involved in nanotube based applications are related to the fabrication and assembly of the CNT. In this paper, in situ nanofabrication methods, involving cutting, bending, and welding of multi-walled carbon nanotube (MWNT) inside a scanning electron microscope (SEM), are presented. These three nanofabrication techniques are further used in the assembly of a CNT based nanostructure. A three dimensional (3D) nanostructure, the letter N, was assembled from a single CNT and fixed to stand on a substrate. Based on the high performance of the proposed techniques, it is suggested that the cutting, bending, and welding techniques inside SEM will become widely utilized in the fabrication and assembly of nanodevices and in the characterization of nanomaterials.
{"title":"Nanoscale Cutting, Bending and Welding in a Nanoassembly","authors":"Toshio Fukudal, Pou Liu","doi":"10.1109/NEMS.2007.352078","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352078","url":null,"abstract":"Carbon nanotube (CNT) can be used as a building block of nanoelectronic mechanical systems (NEMS). The main problems involved in nanotube based applications are related to the fabrication and assembly of the CNT. In this paper, in situ nanofabrication methods, involving cutting, bending, and welding of multi-walled carbon nanotube (MWNT) inside a scanning electron microscope (SEM), are presented. These three nanofabrication techniques are further used in the assembly of a CNT based nanostructure. A three dimensional (3D) nanostructure, the letter N, was assembled from a single CNT and fixed to stand on a substrate. Based on the high performance of the proposed techniques, it is suggested that the cutting, bending, and welding techniques inside SEM will become widely utilized in the fabrication and assembly of nanodevices and in the characterization of nanomaterials.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133282709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352211
N. Changsan, T. Srichana
RIF encapsulated liposome vesicles were prepared by chloroform film method followed by freeze drying technique to obtain a dry powder for aerosol delivery. The freeze drying conditions were designed according to the DSC results of the liposome suspension. Three sugars (mannitol, lactose and trehalose) were used as a cryoprotectant of liposome dry powder. NR 8383 cell line was used to determine immunological activation and toxicity of liposome products when LPS from E.coli was used as a positive control. High cholesterol content in the formulation created higher rigid bilayer membrane of liposome vesicle than the lower cholesterol content formulation thus provided a better physical stability. The lipid content had influenced on degree of encapsulation, higher lipid content in formulation produced higher % encapsulation. Mannitol was a suitable sugar for this dry powder aerosol when it provided a free flowing powder with an MMAD less than 5 mum (3.35 mum). In addition, RIF in liposome dry powder form showed better chemical stability than in suspension form after they were kept for 6 weeks both at 4degC and room temperature. The reconstituted liposome powder in PBS pH 7.4 gave the encapsulation about 22%. The products did not cause toxicity to the cell line and did not activate immune responses since the cell produced very low level of toxic cytokines (IL-lbeta and TNF-alpha) when compared to LPS. This indicates that the particles are able to reach alveoli without stimulation of immunological response and safe to alveolar macrophage.
{"title":"Factors Influencing the Properties of Rifampicin Liposome and Applications for Dry Powder Inhaler","authors":"N. Changsan, T. Srichana","doi":"10.1109/NEMS.2007.352211","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352211","url":null,"abstract":"RIF encapsulated liposome vesicles were prepared by chloroform film method followed by freeze drying technique to obtain a dry powder for aerosol delivery. The freeze drying conditions were designed according to the DSC results of the liposome suspension. Three sugars (mannitol, lactose and trehalose) were used as a cryoprotectant of liposome dry powder. NR 8383 cell line was used to determine immunological activation and toxicity of liposome products when LPS from E.coli was used as a positive control. High cholesterol content in the formulation created higher rigid bilayer membrane of liposome vesicle than the lower cholesterol content formulation thus provided a better physical stability. The lipid content had influenced on degree of encapsulation, higher lipid content in formulation produced higher % encapsulation. Mannitol was a suitable sugar for this dry powder aerosol when it provided a free flowing powder with an MMAD less than 5 mum (3.35 mum). In addition, RIF in liposome dry powder form showed better chemical stability than in suspension form after they were kept for 6 weeks both at 4degC and room temperature. The reconstituted liposome powder in PBS pH 7.4 gave the encapsulation about 22%. The products did not cause toxicity to the cell line and did not activate immune responses since the cell produced very low level of toxic cytokines (IL-lbeta and TNF-alpha) when compared to LPS. This indicates that the particles are able to reach alveoli without stimulation of immunological response and safe to alveolar macrophage.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133059398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352194
B. Chu, E. Pierstorff, D. Ho
We have utilized a block copolymeric thin film as a modality to template the deposition of single-walled carbon nanotubes towards applications in single cell interrogation. Transmembrane studies of cellular activity (e.g. neurons, cardiomyocytes, etc.) have often been limited by the invasiveness of probe-induced membrane rupture. This often precludes chronic activity analysis. We have developed a copolymer-carbon nanotube (P-CNT) hybrid material for potential applications in non-invasive cell probing with attenuated inflammation due to the biomimetic stiffness of the copolymer coupled with nanoscale dimensions of the P-CNT complex. We applied both a diblock copolymer comprised of poly(ethylene oxide-b-methyl methacrylate; PEO-PMMA) as well as an acrylate-terminated amphiphilic `ABA' triblock copolymer comprised of polymethyloxazoline-polydimethylsiloxane-polymethyloxazoline; PMOXA-PDMS-PMOXA) as the supporting matrix for carbon nanotube deposition via the Langmuir-Blodgett methodology. This enabled the suspension of the carbon nanotubes on the air-water interface for transfer to a gold substrate. Cyclic voltammetry measurements confirmed that the CNT's were interfaced directly with the gold substrates to enable electrical functionality. In addition, cellular adhesion to the polymeric substrate was demonstrated, confirming the biocompatibility of the P-CNT material. CNT-coated electrodes were also examined as biological electrodes for the monitoring of oxidation-reduction processes driven by the cytochrome c mediator, where CNT/polymer-coated surfaces were also capable of facilitating anti-protein adsorption, resulting in the observation of reversible electron transfer between the protein and electrode. This was demonstrated via acquisition of pronounced anodic and cathodic peaks with peak separations of 64mV, which confirmed a reversible transfer process.
{"title":"Polymer-Enabled Carbon Nanotube Deposition for Cellular Interrogation Applications","authors":"B. Chu, E. Pierstorff, D. Ho","doi":"10.1109/NEMS.2007.352194","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352194","url":null,"abstract":"We have utilized a block copolymeric thin film as a modality to template the deposition of single-walled carbon nanotubes towards applications in single cell interrogation. Transmembrane studies of cellular activity (e.g. neurons, cardiomyocytes, etc.) have often been limited by the invasiveness of probe-induced membrane rupture. This often precludes chronic activity analysis. We have developed a copolymer-carbon nanotube (P-CNT) hybrid material for potential applications in non-invasive cell probing with attenuated inflammation due to the biomimetic stiffness of the copolymer coupled with nanoscale dimensions of the P-CNT complex. We applied both a diblock copolymer comprised of poly(ethylene oxide-b-methyl methacrylate; PEO-PMMA) as well as an acrylate-terminated amphiphilic `ABA' triblock copolymer comprised of polymethyloxazoline-polydimethylsiloxane-polymethyloxazoline; PMOXA-PDMS-PMOXA) as the supporting matrix for carbon nanotube deposition via the Langmuir-Blodgett methodology. This enabled the suspension of the carbon nanotubes on the air-water interface for transfer to a gold substrate. Cyclic voltammetry measurements confirmed that the CNT's were interfaced directly with the gold substrates to enable electrical functionality. In addition, cellular adhesion to the polymeric substrate was demonstrated, confirming the biocompatibility of the P-CNT material. CNT-coated electrodes were also examined as biological electrodes for the monitoring of oxidation-reduction processes driven by the cytochrome c mediator, where CNT/polymer-coated surfaces were also capable of facilitating anti-protein adsorption, resulting in the observation of reversible electron transfer between the protein and electrode. This was demonstrated via acquisition of pronounced anodic and cathodic peaks with peak separations of 64mV, which confirmed a reversible transfer process.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"28 47","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114050204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352007
M. Esashi
MEMS (Micro Electro Mechanical Systems) have been fabricated using advanced micromachining based on an extended semiconductor microfabrication. Sophisticated MEMS device used as a high performance rotating gyroscope for navigation control systems was developed. A 1.5 mm diameter silicon ring rotor is electrostatically levitated and rotated at 75,000rpm using high speed digital signal control. Two-axes rotation and three-axes acceleration are detected simultaneously with high precision. Small size packaged MEMS devices such as integrated capacitive pressure sensor, diaphragm vacuum sensor and MEMS relay for LSI tester have been fabricated using a wafer level packaging using a glass with electrical feedthroughs. The MEMS relay performs high frequency response up to 20 GHz and high reliability owing to the hermetic sealing. Active catheters, fine blood pressure sensors used in a blood vessel and endoscope with laser therapy function have been developed for minimal invasive medicine using MEMS based assembly. As NEMS (Nano Electro Mechanical Systems) which include nano structure, arrayed systems as multiprobe data storage and massively parallel electron beam lithography system have been developed using a glass with high density electrical feedthroughs. Monolithic XYZ-stage has been also developed for the arrayed systems. Highly sensitive cantilever resonator and micro probes have been also developed as the NEMS.
{"title":"Workshop Speech: Commercialization of MEMS/NEMS in Tohoku University Open Collaboration","authors":"M. Esashi","doi":"10.1109/NEMS.2007.352007","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352007","url":null,"abstract":"MEMS (Micro Electro Mechanical Systems) have been fabricated using advanced micromachining based on an extended semiconductor microfabrication. Sophisticated MEMS device used as a high performance rotating gyroscope for navigation control systems was developed. A 1.5 mm diameter silicon ring rotor is electrostatically levitated and rotated at 75,000rpm using high speed digital signal control. Two-axes rotation and three-axes acceleration are detected simultaneously with high precision. Small size packaged MEMS devices such as integrated capacitive pressure sensor, diaphragm vacuum sensor and MEMS relay for LSI tester have been fabricated using a wafer level packaging using a glass with electrical feedthroughs. The MEMS relay performs high frequency response up to 20 GHz and high reliability owing to the hermetic sealing. Active catheters, fine blood pressure sensors used in a blood vessel and endoscope with laser therapy function have been developed for minimal invasive medicine using MEMS based assembly. As NEMS (Nano Electro Mechanical Systems) which include nano structure, arrayed systems as multiprobe data storage and massively parallel electron beam lithography system have been developed using a glass with high density electrical feedthroughs. Monolithic XYZ-stage has been also developed for the arrayed systems. Highly sensitive cantilever resonator and micro probes have been also developed as the NEMS.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121750691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352243
Yuhong Long, Liangcai Xiong, T. Shi, Zirong Tang
To further understand the behavior of laser-induced electrochemical etching process, the experiments of micromachining silicon by laser-induced electrochemical etching were carried out. 248nm excimer laser as light source is adopted in this work with the power of 109W/cm2 for the first time and KOH solution is used as electrolyte. Based on the experiment results, the surface images and etching rate are analyzed in detail. It is verified that the compound technique is a combination of laser etching, electrochemical etching and coupling etching, and laser etching is dominating in the compound process. Besides, both liquid-enhanced pressure and jet shock pressure can preferably improve the etching rate. At the same time, the anisotropic etching stop of silicon in alkaline solution is solved in this study. As a result, this process can be applied to transfer pattern without mask, and it possesses the ability of machining large aspect ratio micro structures.
{"title":"Study of Excimer Laser Electrochemical Etching Silicon","authors":"Yuhong Long, Liangcai Xiong, T. Shi, Zirong Tang","doi":"10.1109/NEMS.2007.352243","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352243","url":null,"abstract":"To further understand the behavior of laser-induced electrochemical etching process, the experiments of micromachining silicon by laser-induced electrochemical etching were carried out. 248nm excimer laser as light source is adopted in this work with the power of 109W/cm2 for the first time and KOH solution is used as electrolyte. Based on the experiment results, the surface images and etching rate are analyzed in detail. It is verified that the compound technique is a combination of laser etching, electrochemical etching and coupling etching, and laser etching is dominating in the compound process. Besides, both liquid-enhanced pressure and jet shock pressure can preferably improve the etching rate. At the same time, the anisotropic etching stop of silicon in alkaline solution is solved in this study. As a result, this process can be applied to transfer pattern without mask, and it possesses the ability of machining large aspect ratio micro structures.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115081582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352045
D. Grieshaber, E. Reimhult, J. Voros
Enzymatic biosensors are expected to play a key-role in bio techno logical and biochemical analysis as shown by the success of glucose sensors in diabetes treatment. The aim of this work is to develop a multiplexed electronic detection system for early cancer diagnostics. Therefore, various enzymes were adsorbed to differently modified surfaces. Electrochemical optical waveguide lightmode spectroscopy (EC-OWLS) and electrochemical quartz crystal microbalance with dissipation (EC-QCM-D) were used to measure the mass and the activity of the adsorbed enzymes. The enzymes were specifically immobilized on a protein resistant PLL-g-PEG surface in order to reduce the loss of activity due to denaturation. In addition, enzymes were also incorporated into DNA-tagged vesicles to increase the signal and therefore the sensor sensitivity. The enzymatic activity of the different systems was compared. To further increase the sensitivity, ferrocyanide was used as an electron mediator.
{"title":"Enzymatic Biosensors towards a Multiplexed Electronic Detection System for Early Cancer Diagnostics","authors":"D. Grieshaber, E. Reimhult, J. Voros","doi":"10.1109/NEMS.2007.352045","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352045","url":null,"abstract":"Enzymatic biosensors are expected to play a key-role in bio techno logical and biochemical analysis as shown by the success of glucose sensors in diabetes treatment. The aim of this work is to develop a multiplexed electronic detection system for early cancer diagnostics. Therefore, various enzymes were adsorbed to differently modified surfaces. Electrochemical optical waveguide lightmode spectroscopy (EC-OWLS) and electrochemical quartz crystal microbalance with dissipation (EC-QCM-D) were used to measure the mass and the activity of the adsorbed enzymes. The enzymes were specifically immobilized on a protein resistant PLL-g-PEG surface in order to reduce the loss of activity due to denaturation. In addition, enzymes were also incorporated into DNA-tagged vesicles to increase the signal and therefore the sensor sensitivity. The enzymatic activity of the different systems was compared. To further increase the sensitivity, ferrocyanide was used as an electron mediator.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115462691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352087
Jiun-Min Wang, Tzu-Yuan Lin, Lung-Jieh Yang
This paper describes about the fabrication and testing of a novel electrohydrodynamic (EHD) micro-boat using parylene MEMS technology. The driven force of micro-boat utilizes the reaction force of the EHD, with planar electrodes, to pump nonpolar liquid. As a result, by applying a DC voltage of 30-40 V the instantaneous moving velocity of the EHD micro-boat is about 6.5 mm/min.
{"title":"Electrohydrodynamic (EHD) Micro-Boat","authors":"Jiun-Min Wang, Tzu-Yuan Lin, Lung-Jieh Yang","doi":"10.1109/NEMS.2007.352087","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352087","url":null,"abstract":"This paper describes about the fabrication and testing of a novel electrohydrodynamic (EHD) micro-boat using parylene MEMS technology. The driven force of micro-boat utilizes the reaction force of the EHD, with planar electrodes, to pump nonpolar liquid. As a result, by applying a DC voltage of 30-40 V the instantaneous moving velocity of the EHD micro-boat is about 6.5 mm/min.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"688 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116169179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352171
Nan Li, Daniel T. Kamei, Chih-Ming Ho
This paper presents a microfluidic device for continuous human blood cell subtype separation using the deterministic lateral displacement principle. Based on their significant size and shape differences, three major cell types of human whole blood - platelets, red blood cells and white blood cells -were demonstrated to be directly separated using a two-stage separation strategy. Even though all white blood cells are spherical and have diameters within a narrow range (8-20mum), the initial limitation for using this principle to separate white blood cell subtypes was conquered by attaching larger polystyrene microbeads to one of the subtypes to amplify the size differences. Specifically, continuous separation of human CD4+ T helper lymphocytes from other white blood cell subtypes was achieved with high purity and recovery due to the underlying high affinity and high specificity of the antigen-antibody interaction used to attach the microbeads to the lymphocytes. With our novel approach, the pure population of one blood cell subtype can be effectively isolated by exploring the deterministic lateral displacement principle, which has the advantages of the simplicity, high speed and high resolution. Because many cells express unique surface markers, this method can theoretically be applied to separate any target cell type from a heterogeneous mixture for downstream analysis.
{"title":"On-Chip Continuous Blood Cell Subtype Separation by Deterministic Lateral Displacement","authors":"Nan Li, Daniel T. Kamei, Chih-Ming Ho","doi":"10.1109/NEMS.2007.352171","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352171","url":null,"abstract":"This paper presents a microfluidic device for continuous human blood cell subtype separation using the deterministic lateral displacement principle. Based on their significant size and shape differences, three major cell types of human whole blood - platelets, red blood cells and white blood cells -were demonstrated to be directly separated using a two-stage separation strategy. Even though all white blood cells are spherical and have diameters within a narrow range (8-20mum), the initial limitation for using this principle to separate white blood cell subtypes was conquered by attaching larger polystyrene microbeads to one of the subtypes to amplify the size differences. Specifically, continuous separation of human CD4+ T helper lymphocytes from other white blood cell subtypes was achieved with high purity and recovery due to the underlying high affinity and high specificity of the antigen-antibody interaction used to attach the microbeads to the lymphocytes. With our novel approach, the pure population of one blood cell subtype can be effectively isolated by exploring the deterministic lateral displacement principle, which has the advantages of the simplicity, high speed and high resolution. Because many cells express unique surface markers, this method can theoretically be applied to separate any target cell type from a heterogeneous mixture for downstream analysis.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116866401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352213
P. Wanichapichart, T. Wongluksanapan, L. Khooburat
This work proposes a method to estimate cell dielectric properties using a rotating electric field. Signals given to four platinum electrodes were from a phase shift unit, which splits an input signal into four of pi/2 phase difference. The unit performs well under frequency below 5 MHz. Rotation patterns of pretreated Tetraselmis sp. were utilized to reveal dielectric information of the cells. The rotation of boiled cells diminished at the lower frequency range, while that of the arsenic pretreated cells was smaller than that of the control when higher arsenic concentration was used. The specific membrane conductance was increased from 0.5 kS.m-1 for the control to 90 kS.m-1 boiled cells. Pretreated cells with arsenic solution at 10 to 100 ppm levels increased the membrane conductance to 8.8 kS.m-1, much less effect compared to the boiled cells. Moreover, 24 hrs pretreatment was long enough for arsenic to penetrate the membrane, and the cytoplasmic permittivity was reduced from 39epsivO to about 13e0, independent of the arsenic levels used. The study can distinguish the viability from the non-viability cells by carefully selected field, frequency, and solution conductivity.
{"title":"Electrorotation: Diagnostic Tool for Abnormality of Marine Phytoplankton Cells","authors":"P. Wanichapichart, T. Wongluksanapan, L. Khooburat","doi":"10.1109/NEMS.2007.352213","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352213","url":null,"abstract":"This work proposes a method to estimate cell dielectric properties using a rotating electric field. Signals given to four platinum electrodes were from a phase shift unit, which splits an input signal into four of pi/2 phase difference. The unit performs well under frequency below 5 MHz. Rotation patterns of pretreated Tetraselmis sp. were utilized to reveal dielectric information of the cells. The rotation of boiled cells diminished at the lower frequency range, while that of the arsenic pretreated cells was smaller than that of the control when higher arsenic concentration was used. The specific membrane conductance was increased from 0.5 kS.m-1 for the control to 90 kS.m-1 boiled cells. Pretreated cells with arsenic solution at 10 to 100 ppm levels increased the membrane conductance to 8.8 kS.m-1, much less effect compared to the boiled cells. Moreover, 24 hrs pretreatment was long enough for arsenic to penetrate the membrane, and the cytoplasmic permittivity was reduced from 39epsivO to about 13e0, independent of the arsenic levels used. The study can distinguish the viability from the non-viability cells by carefully selected field, frequency, and solution conductivity.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"32 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116357748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-04-23DOI: 10.1109/NEMS.2007.352008
O. Tabata
The role of University in MNT has been becoming more and more essential since the Micro Nano Technology (MNT) requires not only innovative seeds to open up a new application fields but also both well-qualified persons in MNT who lead this field. To meet these requirements, interdisciplinary and international collaboration and cooperation in education and research is crucially important. Firstly, part of related activities related to MNT in Kyoto University are introduced, such as the education program in MNT, the organization of newly established Micro Engineering Department, and research organization of Research Institute of Nano Science & Technology which is the lateral organization of several departments and colleges on nanotechnology. Secondly, two research topics in MNT, nano-scale material mechanical property characterization and nano-components assembly on MEMS which are pursued at Micro Nano System Laboratory are introduced as the tentative themes for further international collaboration and cooperation.
{"title":"Workshop Speech: Role of University Research for Open Innovations in MNT","authors":"O. Tabata","doi":"10.1109/NEMS.2007.352008","DOIUrl":"https://doi.org/10.1109/NEMS.2007.352008","url":null,"abstract":"The role of University in MNT has been becoming more and more essential since the Micro Nano Technology (MNT) requires not only innovative seeds to open up a new application fields but also both well-qualified persons in MNT who lead this field. To meet these requirements, interdisciplinary and international collaboration and cooperation in education and research is crucially important. Firstly, part of related activities related to MNT in Kyoto University are introduced, such as the education program in MNT, the organization of newly established Micro Engineering Department, and research organization of Research Institute of Nano Science & Technology which is the lateral organization of several departments and colleges on nanotechnology. Secondly, two research topics in MNT, nano-scale material mechanical property characterization and nano-components assembly on MEMS which are pursued at Micro Nano System Laboratory are introduced as the tentative themes for further international collaboration and cooperation.","PeriodicalId":364039,"journal":{"name":"2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114746411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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