1
|
Zhang H, Dai X, Hu Y, Wu D, Jing G, Li Y, Fan G. Non-coplanar misalignment optical waveguide cantilever sensor with a monotonic response in a large operation range. APPLIED OPTICS 2022; 61:10446-10450. [PMID: 36607104 DOI: 10.1364/ao.473498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
This paper reports a non-coplanar misalignment optical waveguide cantilever sensor realizing a monotonic response with a large operation range. A 1×2 Y-branch optical power splitter cantilever structure was designed, and one of the branches was reduced in thickness at the end, as a non-coplanar structure with respect to another. The misalignment coupling of the two branches due to the thickness of one branch leads to a monotonic response of an optical waveguide cantilever sensor. The simulation results showed a monotonic response with a sensitivity of 6×10-4 n m -1 in a large operation range of -1 to 1 µm.
Collapse
|
2
|
Hu S, Huang W, Meng F, Lam RHW, Lau D. Adhesion Strengthening Mechanism of Carbon Nanotube-Embedded Epoxy Composites: A Fracture-Based Approach. ACS APPLIED MATERIALS & INTERFACES 2022; 14:7221-7229. [PMID: 35019263 DOI: 10.1021/acsami.1c20282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Interfacial bonding integrity between different materials is critical to maintain the functionality of the entire physical system in any scale, ranging from building structures down to semiconductor transistors. For example, micro-patterned polymers embedded with conductive nanoparticles [e.g., carbon nanotubes (CNTs)] bonded with integrated circuits have been applied as many emerging chemical/biological microelectronic sensors. Nonetheless, it is challenging to measure and ensure the interfacial bonding integrity between materials for consistent and sustainable operations. Herein, we apply multiple interface characterization methods based on micro-engineering and microscopy as an integrative approach to reveal the mechanism of interfacial reinforcement by adding CNTs in a matrix material. An epoxy/CNT micro-beam is fabricated onto a silicon substrate, sandwiching a gold layer as an interfacial precrack. Superlayers of chromium are then repeatedly deposited onto the microstructure, inducing stepwise increasing stress over the materials and the corresponding micro-beam bending after detachment from the bonded interface. Accordingly, we can quantify key interfacial fracture parameters such as crack length, steady-state energy release rate, and fracture toughness. By further examining the formation and distribution of the micro-/nanostructures along the debonded interface using bright-field microscopy, 3D fluorescence imaging, and scanning electron microscopy, we can identify the underlying dominant interfacial strengthening and fracture toughening mechanisms. We further compare experimental results and theoretical predictions to quantify the interfacial bonding properties between epoxy/CNT and silicon and unveil the underlying reinforcement mechanisms. The results provide insights to develop polymer/nanoparticle composites with reinforced interfacial bonding integrity for more sustainable and reliable applications including microelectronics, surface coatings, and adhesive materials.
Collapse
Affiliation(s)
- Shuhuan Hu
- Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China
- BGI-Shenzhen, Shenzhen, Guangdong 518083, China
- Guangdong High-throughput Sequencing Research Center, Shenzhen, Guangdong 518000, China
| | - Wei Huang
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China
| | - Fanchao Meng
- BGI-Shenzhen, Shenzhen, Guangdong 518083, China
- Guangdong High-throughput Sequencing Research Center, Shenzhen, Guangdong 518000, China
| | - Raymond H W Lam
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, Guangdong 518057, China
| | - Denvid Lau
- Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, Guangdong 518057, China
| |
Collapse
|
3
|
Dong M, Oyunbaatar NE, Kanade PP, Kim DS, Lee DW. Real-Time Monitoring of Changes in Cardiac Contractility Using Silicon Cantilever Arrays Integrated with Strain Sensors. ACS Sens 2021; 6:3556-3563. [PMID: 34554741 DOI: 10.1021/acssensors.1c00486] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This paper proposes the use of sensor-integrated silicon cantilever arrays to measure drug-induced cardiac toxicity in real time. The proposed cantilever sensors, unlike the conventional electrophysiological methods, aim to evaluate cardiac toxicity by measuring the contraction force of the cardiomyocytes corresponding to the target drugs. The surface of the silicon cantilever consists of microgrooves to maximize the alignment and the contraction force of the cardiomyocytes. This type of surface pattern also helps in the maturation of the cardiomyocytes by increasing the sarcomere length. The preliminary characterization of the cantilever sensors was performed on the cantilever surface, with the cardiomyocytes seeded with a density of 1000 cells/mm2, and the cardiac contractility was measured as a function of the culture days. The change in the contraction force of the cardiomyocytes due to the drug concentration was successfully measured through the integrated strain sensor in the culture media. The reliability of the sensor-integrated cantilevers and the feasibility of their mass production ensure that they meet the practical requirements in the medical applications.
Collapse
Affiliation(s)
- Mingming Dong
- MEMS and Nanotechnology Laboratory, School of Mechanical Systems Engineering, Chonnam National University, Gwangju 61186, Korea
| | - Nomin-Erdene Oyunbaatar
- MEMS and Nanotechnology Laboratory, School of Mechanical Systems Engineering, Chonnam National University, Gwangju 61186, Korea
| | - Pooja P. Kanade
- MEMS and Nanotechnology Laboratory, School of Mechanical Systems Engineering, Chonnam National University, Gwangju 61186, Korea
| | - Dong-Su Kim
- MEMS and Nanotechnology Laboratory, School of Mechanical Systems Engineering, Chonnam National University, Gwangju 61186, Korea
| | - Dong-Weon Lee
- MEMS and Nanotechnology Laboratory, School of Mechanical Systems Engineering, Chonnam National University, Gwangju 61186, Korea
- Center for Next Generation Sensor Research and Development, Chonnam National University, Gwangju 61186, Korea
| |
Collapse
|
4
|
Mollaei F, Aliparast P, Naghash A. Multiscale Simulation of Adsorption Based Microcantilever Biosensors for Radiation Exposure Effects. IRANIAN JOURNAL OF BIOTECHNOLOGY 2021; 18:e2317. [PMID: 33542938 PMCID: PMC7856398 DOI: 10.30498/ijb.2020.134636.2317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background This article is focused on biological measurements based on molecular interactions. The specific biomarker implemented for radiation biosensor is FLT3, which bears changes in the body regarding radiation exposure. Experimental results of sensing vancomycin verify the overall results of two steps of numerical methods for different scales. Objectives The aim is to provide adequate modeling procedures to predict sensory data. Multiscale modeling is implemented to simulate molecular interaction and its consequent micro mechanical effects. The method is implemented to calculate surface traction of microcantilever biosensor. Materials and Methods The method consists of molecular dynamics simulation of adsorption process by implementing classical mechanics theory to calculate the final response of the sensor as tip deflection. The sequential information transaction is assumed between the physical parameters of two governing scales. The numerical method consists of the location of particles providing for a nano-metric periodic boundary conditioned functionalized surface implemented, and the numerical thermodynamic formula is, in turn, use energy parameters to acquire macro-mechanical deflection of a specific microcantilever. Also, novel sensitivity analysis of the results as the adsorption process moves toward more saturated substrate provided. Results Verification of the simulation method for Vancomycin sensing results enjoys less than 20 percent of deviation regarding the experimental data. The standard deviation of 0.054 in the final expected response of the sensor is calculated as the accuracy of the radiation biosensor based on FLT3. Conclusions The method is still to reach a correlation between the concentration of target molecules in solution and the number of adsorbed molecules per area of the sensor. A scaled correlation between sensor's response and the amount of biomarker is found using tip deflection of a sample designed microcantilever. Around one micrometer deflection that can be read out using various conventional methods was observed at saturation of adsorption surface. The analyses provide adequate data to design a sensor capable of measuring the effect of cosmic radiation to the human body.
Collapse
Affiliation(s)
- Fouad Mollaei
- Aerospace Research Institute, Ministry of Science and Research and Technology, Tehran, Iran.,Aerospace Engineering Department, Amirkabir University of Technology, Tehran, Iran
| | - Peiman Aliparast
- Aerospace Research Institute, Ministry of Science and Research and Technology, Tehran, Iran
| | - Abolghasem Naghash
- Aerospace Engineering Department, Amirkabir University of Technology, Tehran, Iran
| |
Collapse
|
5
|
Çağlayan Z, Demircan Yalçın Y, Külah H. A Prominent Cell Manipulation Technique in BioMEMS: Dielectrophoresis. MICROMACHINES 2020; 11:E990. [PMID: 33153069 PMCID: PMC7693018 DOI: 10.3390/mi11110990] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/22/2020] [Accepted: 10/28/2020] [Indexed: 12/17/2022]
Abstract
BioMEMS, the biological and biomedical applications of micro-electro-mechanical systems (MEMS), has attracted considerable attention in recent years and has found widespread applications in disease detection, advanced diagnosis, therapy, drug delivery, implantable devices, and tissue engineering. One of the most essential and leading goals of the BioMEMS and biosensor technologies is to develop point-of-care (POC) testing systems to perform rapid prognostic or diagnostic tests at a patient site with high accuracy. Manipulation of particles in the analyte of interest is a vital task for POC and biosensor platforms. Dielectrophoresis (DEP), the induced movement of particles in a non-uniform electrical field due to polarization effects, is an accurate, fast, low-cost, and marker-free manipulation technique. It has been indicated as a promising method to characterize, isolate, transport, and trap various particles. The aim of this review is to provide fundamental theory and principles of DEP technique, to explain its importance for the BioMEMS and biosensor fields with detailed references to readers, and to identify and exemplify the application areas in biosensors and POC devices. Finally, the challenges faced in DEP-based systems and the future prospects are discussed.
Collapse
Affiliation(s)
- Zeynep Çağlayan
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- METU MEMS Research and Application Center, Ankara 06800, Turkey
| | - Yağmur Demircan Yalçın
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- Mikro Biyosistemler Electronics Inc., Ankara 06530, Turkey
| | - Haluk Külah
- Department of Electrical and Electronics Engineering, Middle East Technical University, Ankara 06800, Turkey; (Z.Ç.); (Y.D.Y.)
- METU MEMS Research and Application Center, Ankara 06800, Turkey
- Mikro Biyosistemler Electronics Inc., Ankara 06530, Turkey
| |
Collapse
|
6
|
Mere V, Dash A, Kallega R, Pratap R, Naik A, Selvaraja SK. On-chip silicon photonics based grating assisted vibration sensor. OPTICS EXPRESS 2020; 28:27495-27505. [PMID: 32988042 DOI: 10.1364/oe.394393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
We present a compact, highly sensitive and scalable on-chip photonic vibration measurement scheme for vibration sensing. The scheme uses a silicon photonic diffraction-grating based sensor integrated underneath a silicon cantilever. We demonstrate a static and dynamic measurement sensitivity (ΔT/Δgap) of 0.6 % change in intensity per nm displacement. The electrostatically driven dynamic response measurement of the grating based sensor shows an excellent agreement with commercial Laser Doppler Vibrometer (LDV) measurement. We demonstrate the thermo-mechanical noise measurement on the cantilever in ambience, which is verified using LDV. A minimum displacement of 1.9 pm is measured with a displacement sensitivity of 10 μW/nm for a measurement bandwidth of 16 Hz. The demonstrated sensitivity is 2 orders of magnitude better than that obtained from measurements of static displacement. We also present a detailed 2D-FDTD simulation and optimization of the grating-based sensor to achieve maximum displacement sensitivity.
Collapse
|
7
|
Integrated Electromechanical Transduction Schemes for Polymer MEMS Sensors. MICROMACHINES 2018; 9:mi9050197. [PMID: 30424130 PMCID: PMC6187334 DOI: 10.3390/mi9050197] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 11/21/2022]
Abstract
Polymer Micro ElectroMechanical Systems (MEMS) have the potential to constitute a powerful alternative to silicon-based MEMS devices for sensing applications. Although the use of commercial photoresists as structural material in polymer MEMS has been widely reported, the integration of functional polymer materials as electromechanical transducers has not yet received the same amount of interest. In this context, we report on the design and fabrication of different electromechanical schemes based on polymeric materials ensuring different transduction functions. Piezoresistive transduction made of carbon nanotube-based nanocomposites with a gauge factor of 200 was embedded within U-shaped polymeric cantilevers operating either in static or dynamic modes. Flexible resonators with integrated piezoelectric transduction were also realized and used as efficient viscosity sensors. Finally, piezoelectric-based organic field effect transistor (OFET) electromechanical transduction exhibiting a record sensitivity of over 600 was integrated into polymer cantilevers and used as highly sensitive strain and humidity sensors. Such advances in integrated electromechanical transduction schemes should favor the development of novel all-polymer MEMS devices for flexible and wearable applications in the future.
Collapse
|
8
|
Zhao R, Sun Y. Polymeric Flexible Immunosensor Based on Piezoresistive Micro-Cantilever with PEDOT/PSS Conductive Layer. SENSORS (BASEL, SWITZERLAND) 2018; 18:E451. [PMID: 29401669 PMCID: PMC5855110 DOI: 10.3390/s18020451] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 01/26/2018] [Accepted: 01/31/2018] [Indexed: 11/16/2022]
Abstract
In this paper, a fully polymeric micro-cantilever with the surface passivation layer of parylene-C and the strain resistor of poly(3,4-ethylenedioxythiophene)/poly (styrene sulfonate) (PEDOT/PSS) was proposed and demonstrated for immunoassays. By optimizing the design and fabrication of the polymeric micro-cantilever, a square resistance of 220 Ω/□ for PEDOT/PSS conductive layer have been obtained. The experimental spring constant and the deflection sensitivity were measured to be 0.017 N/m and 8.59 × 10-7 nm-1, respectively. The biological sensing performances of polymeric micro-cantilever were investigated by the immunoassay for human immunoglobulin G (IgG). The immunosensor was experimentally demonstrated to have a linear behavior for the detection of IgG within the concentrations of 10~100 ng/mL with a limit of detection (LOD) of 10 ng/mL. The experimental results indicate that the proposed polymeric flexible conductive layer-based sensors are capable of detecting trace biological substances.
Collapse
Affiliation(s)
- Rui Zhao
- School of Instrument and Electronics, North University of China, Taiyuan 030051, China.
| | - Ying Sun
- School of Instrument and Electronics, North University of China, Taiyuan 030051, China.
| |
Collapse
|
9
|
Mathew R, Ravi Sankar A. A Review on Surface Stress-Based Miniaturized Piezoresistive SU-8 Polymeric Cantilever Sensors. NANO-MICRO LETTERS 2018; 10:35. [PMID: 30393684 PMCID: PMC6199092 DOI: 10.1007/s40820-018-0189-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/02/2018] [Indexed: 05/30/2023]
Abstract
In the last decade, microelectromechanical systems (MEMS) SU-8 polymeric cantilevers with piezoresistive readout combined with the advances in molecular recognition techniques have found versatile applications, especially in the field of chemical and biological sensing. Compared to conventional solid-state semiconductor-based piezoresistive cantilever sensors, SU-8 polymeric cantilevers have advantages in terms of better sensitivity along with reduced material and fabrication cost. In recent times, numerous researchers have investigated their potential as a sensing platform due to high performance-to-cost ratio of SU-8 polymer-based cantilever sensors. In this article, we critically review the design, fabrication, and performance aspects of surface stress-based piezoresistive SU-8 polymeric cantilever sensors. The evolution of surface stress-based piezoresistive cantilever sensors from solid-state semiconductor materials to polymers, especially SU-8 polymer, is discussed in detail. Theoretical principles of surface stress generation and their application in cantilever sensing technology are also devised. Variants of SU-8 polymeric cantilevers with different composition of materials in cantilever stacks are explained. Furthermore, the interdependence of the material selection, geometrical design parameters, and fabrication process of piezoresistive SU-8 polymeric cantilever sensors and their cumulative impact on the sensor response are also explained in detail. In addition to the design-, fabrication-, and performance-related factors, this article also describes various challenges in engineering SU-8 polymeric cantilevers as a universal sensing platform such as temperature and moisture vulnerability. This review article would serve as a guideline for researchers to understand specifics and functionality of surface stress-based piezoresistive SU-8 cantilever sensors.
Collapse
Affiliation(s)
- Ribu Mathew
- School of Electronics Engineering (SENSE), Vellore Institute of Technology (VIT) Chennai, Chennai, Tamil Nadu 600127 India
| | - A. Ravi Sankar
- School of Electronics Engineering (SENSE), Vellore Institute of Technology (VIT) Chennai, Chennai, Tamil Nadu 600127 India
| |
Collapse
|
10
|
Choi YS, Gwak MJ, Lee DW. Polymeric cantilever integrated with PDMS/graphene composite strain sensor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:105004. [PMID: 27802725 DOI: 10.1063/1.4962925] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper describes the mechanical and electrical characteristics of a polydimethylsiloxane (PDMS) cantilever integrated with a high-sensitivity strain sensor. The strain sensor is fabricated using PDMS and graphene flakes that are uniformly distributed in the PDMS. In order to prepare PDMS/graphene composite with uniform resistance, a tetrahydrofuran solution is used to decrease the viscosity of a PDMS base polymer solution. A horn-type sonicator is then used to mix the base polymer with graphene flakes. Low viscosity of the base polymer solution improves the reliability and reproducibility of the PDMS/graphene composite for strain sensor applications. After dicing the composite into the desired sensor shape, a tensile test is performed. The experimental results show that the composite with a concentration of 30 wt.% exhibits a linear response up to a strain rate of 9%. The graphene concentration of the prepared materials affects the gauge factor, which at 20% graphene concentration reaches about 50, and with increasing graphene concentration to 30% decreases to 9. Furthermore, photolithography, PDMS casting, and a stencil process are used to fabricate a PDMS cantilever with an integrated strain sensor. The change in resistance of the integrated PDMS/graphene sensor is characterized with respect to the displacement of the cantilever of within 500 μm. The experimental results confirmed that the prepared PDMS/graphene based sensor has the potential for high-sensitive biosensor applications.
Collapse
Affiliation(s)
- Young-Soo Choi
- MEMS and Nanotechnology Lab, School of Mechanical Engineering Chonnam National University, Gwangju 500757, South Korea
| | - Min-Joo Gwak
- MEMS and Nanotechnology Lab, School of Mechanical Engineering Chonnam National University, Gwangju 500757, South Korea
| | - Dong-Weon Lee
- MEMS and Nanotechnology Lab, School of Mechanical Engineering Chonnam National University, Gwangju 500757, South Korea
| |
Collapse
|
11
|
Durga Prakash M, Vanjari SRK, Sharma CS, Singh SG. Ultrasensitive, Label Free, Chemiresistive Nanobiosensor Using Multiwalled Carbon Nanotubes Embedded Electrospun SU-8 Nanofibers. SENSORS (BASEL, SWITZERLAND) 2016; 16:E1354. [PMID: 27563905 PMCID: PMC5038632 DOI: 10.3390/s16091354] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/24/2016] [Accepted: 07/28/2016] [Indexed: 02/06/2023]
Abstract
This paper reports the synthesis and fabrication of aligned electrospun nanofibers derived out of multiwalled carbon nanotubes (MWCNTs) embedded SU-8 photoresist, which are targeted towards ultrasensitive biosensor applications. The ultrasensitivity (detection in the range of fg/mL) and the specificity of these biosensors were achieved by complementing the inherent advantages of MWCNTs such as high surface to volume ratio and excellent electrical and transduction properties with the ease of surface functionalization of SU-8. The electrospinning process was optimized to precisely align nanofibers in between two electrodes of a copper microelectrode array. MWCNTs not only enhance the conductivity of SU-8 nanofibers but also act as transduction elements. In this paper, MWCNTs were embedded way beyond the percolation threshold and the optimum percentage loading of MWCNTs for maximizing the conductivity of nanofibers was figured out experimentally. As a proof of concept, the detection of myoglobin, an important biomarker for on-set of Acute Myocardial Infection (AMI) has been demonstrated by functionalizing the nanofibers with anti-myoglobin antibodies and carrying out detection using a chemiresistive method. This simple and robust device yielded a detection limit of 6 fg/mL.
Collapse
Affiliation(s)
- Matta Durga Prakash
- Department of Electrical Engineering, Indian Institute of Technology Hyderabad, Hyderabad 502205, India.
| | - Siva Rama Krishna Vanjari
- Department of Electrical Engineering, Indian Institute of Technology Hyderabad, Hyderabad 502205, India.
| | - Chandra Shekhar Sharma
- Department of Chemical Engineering, Indian Institute of Technology Hyderabad, Hyderabad 502205, India.
| | - Shiv Govind Singh
- Department of Electrical Engineering, Indian Institute of Technology Hyderabad, Hyderabad 502205, India.
| |
Collapse
|
12
|
Lee JS, Song J, Kim SO, Kim S, Lee W, Jackman JA, Kim D, Cho NJ, Lee J. Multifunctional hydrogel nano-probes for atomic force microscopy. Nat Commun 2016; 7:11566. [PMID: 27199165 PMCID: PMC4876479 DOI: 10.1038/ncomms11566] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 04/08/2016] [Indexed: 11/10/2022] Open
Abstract
Since the invention of the atomic force microscope (AFM) three decades ago, there have been numerous advances in its measurement capabilities. Curiously, throughout these developments, the fundamental nature of the force-sensing probe—the key actuating element—has remained largely unchanged. It is produced by long-established microfabrication etching strategies and typically composed of silicon-based materials. Here, we report a new class of photopolymerizable hydrogel nano-probes that are produced by bottom-up fabrication with compressible replica moulding. The hydrogel probes demonstrate excellent capabilities for AFM imaging and force measurement applications while enabling programmable, multifunctional capabilities based on compositionally adjustable mechanical properties and facile encapsulation of various nanomaterials. Taken together, the simple, fast and affordable manufacturing route and multifunctional capabilities of hydrogel AFM nano-probes highlight the potential of soft matter mechanical transducers in nanotechnology applications. The fabrication scheme can also be readily utilized to prepare hydrogel cantilevers, including in parallel arrays, for nanomechanical sensor devices. Atomic force microscopy typically employs hard tips to map the surface topology of a sample, with sub-nanometre resolution. Here, the authors instead develop softer hydrogel probes, which show potential for multifunctional measurement capabilities beyond that of conventional systems.
Collapse
Affiliation(s)
- Jae Seol Lee
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| | - Jungki Song
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| | - Seong Oh Kim
- School of Materials Science and Engineering and Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553, Singapore
| | - Seokbeom Kim
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| | - Wooju Lee
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| | - Joshua A Jackman
- School of Materials Science and Engineering and Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553, Singapore
| | - Dongchoul Kim
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| | - Nam-Joon Cho
- School of Materials Science and Engineering and Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
| | - Jungchul Lee
- Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 04107, South Korea
| |
Collapse
|
13
|
Agarwal DK, Maheshwari N, Mukherji S, Rao VR. Asymmetric immobilization of antibodies on a piezo-resistive micro-cantilever surface. RSC Adv 2016. [DOI: 10.1039/c6ra01440b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
For cantilever-based MEMS sensors, selective chemical modification of the sensing surface is used for the detection of chemical and biological analytes.
Collapse
Affiliation(s)
- Dilip Kumar Agarwal
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - Nidhi Maheshwari
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - Soumyo Mukherji
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| | - V. Ramgopal Rao
- Centre of Excellence in Nanoelectronics
- Dept. of Electrical Engineering
- IIT Bombay
- Mumbai
- India
| |
Collapse
|
14
|
Ansari MZ, Cho C. An optimised silicon piezoresistive microcantilever sensor for surface stress studies. MICROSYSTEM TECHNOLOGIES : SENSORS, ACTUATORS, SYSTEMS INTEGRATION 2015; 22:2279-2285. [PMID: 32214690 PMCID: PMC7088182 DOI: 10.1007/s00542-015-2615-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/29/2015] [Indexed: 06/10/2023]
Abstract
Surface stress is a versatile and efficient means to study various physical, chemical, biochemical and biological processes. This work focuses on developing high sensitive piezoresistive microcantilever designs to study surface stress. The cantilevers are made of silicon with rectangular holes at their base that also circumscribe a piezoresistor sensing element. To find the optimum design, the effects of change in cantilever width, rectangular hole length and type of dopant on mechanical properties like deflection, frequency and maximum stress are characterised using finite element analysis software. The surface stress sensitivity characteristics of the different cantilever designs is ascertained by applying a surface stress on their top surfaces. Results show that the sensitivity is increased by increasing the cantilever width as well as the length of the hole and the sensitivity of p-type designs is more than two times the n-type.
Collapse
Affiliation(s)
- Mohd. Zahid Ansari
- PDPM-Indian Institute of Information Technology, Design and Manufacturing-Jabalpur, Khamaria, Jabalpur, 482-005 MP India
| | - Chongdu Cho
- Department of Mechanical Engineering, Inha University, 100 Inha-Ro, Nam-Ku, Incheon, 402-751 Republic of Korea
| |
Collapse
|
15
|
Gopinath PG, Anitha VR, Mastani SA. Microcantilever based Biosensor for Disease Detection Applications. ACTA ACUST UNITED AC 2015. [DOI: 10.12720/jomb.4.4.307-311] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
16
|
Kandpal M, Sharan C, Palaparthy V, Tiwary N, Poddar P, Rao VR. Spin-coatable, photopatternable magnetic nanocomposite thin films for MEMS device applications. RSC Adv 2015. [DOI: 10.1039/c5ra15706d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Magnetic nanomaterials' (especially metals) air stability and compatibility with standard micro-fabrication technologies are often a concern for development of MEMS-based magnetic devices.
Collapse
Affiliation(s)
- M. Kandpal
- Centre for Excellence in Nanoelectronics
- Department of Electrical Engineering
- Indian Institute of Technology
- Bombay
- India
| | - C. Sharan
- Physical & Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - V. Palaparthy
- Centre for Excellence in Nanoelectronics
- Department of Electrical Engineering
- Indian Institute of Technology
- Bombay
- India
| | - N. Tiwary
- Centre for Excellence in Nanoelectronics
- Department of Electrical Engineering
- Indian Institute of Technology
- Bombay
- India
| | - P. Poddar
- Physical & Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune
- India
| | - V. Ramgopal Rao
- Centre for Excellence in Nanoelectronics
- Department of Electrical Engineering
- Indian Institute of Technology
- Bombay
- India
| |
Collapse
|
17
|
Wahid KAA, Lee HW, Shazni MA, Azid IA. Investigation on the effect of different design of SCR on the change of resistance in piezoresistive micro cantilever. MICROSYSTEM TECHNOLOGIES 2014; 20:1079-1083. [DOI: 10.1007/s00542-013-1784-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
|
18
|
Mehrabani S, Maker AJ, Armani AM. Hybrid integrated label-free chemical and biological sensors. SENSORS (BASEL, SWITZERLAND) 2014; 14:5890-928. [PMID: 24675757 PMCID: PMC4029679 DOI: 10.3390/s140405890] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 03/10/2014] [Accepted: 03/14/2014] [Indexed: 12/13/2022]
Abstract
Label-free sensors based on electrical, mechanical and optical transduction methods have potential applications in numerous areas of society, ranging from healthcare to environmental monitoring. Initial research in the field focused on the development and optimization of various sensor platforms fabricated from a single material system, such as fiber-based optical sensors and silicon nanowire-based electrical sensors. However, more recent research efforts have explored designing sensors fabricated from multiple materials. For example, synthetic materials and/or biomaterials can also be added to the sensor to improve its response toward analytes of interest. By leveraging the properties of the different material systems, these hybrid sensing devices can have significantly improved performance over their single-material counterparts (better sensitivity, specificity, signal to noise, and/or detection limits). This review will briefly discuss some of the methods for creating these multi-material sensor platforms and the advances enabled by this design approach.
Collapse
Affiliation(s)
- Simin Mehrabani
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.
| | - Ashley J Maker
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.
| | - Andrea M Armani
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.
| |
Collapse
|
19
|
Lim YC, Kouzani AZ, Duan W, Dai XJ, Kaynak A, Mair D. A surface-stress-based microcantilever aptasensor. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2014; 8:15-24. [PMID: 24681916 DOI: 10.1109/tbcas.2013.2286255] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biosensors based on microcantilevers convert biological recognition events into measurable mechanical displacements. They offer advantages such as small size, low sample volume, label-free detection, ease of integration, high-throughput analysis, and low development cost. The design and development of a microcantilever-based aptasensor employing SU-8 polymer as the fabrication material is presented in this paper. Aptamers are employed as bioreceptor elements because they exhibit superior specificity compared to antibodies due to their small size and physicochemical stability. To immobilise thrombin DNA aptamer on the bare SU-8 surface of the aptasensor, a combined plasma mode treatment method is implemented which modifies the surface of the aptasensor. Label-free detection of thrombin molecules using the fabricated aptasensor is successfully demonstrated. The measured deflection is one order of magnitude higher than that of a silicon nitride microcantilever biosensor. The developed aptasensor also demonstrates high specificity.
Collapse
|
20
|
Bache M, Bosco FG, Brøgger AL, Frøhling KB, Alstrøm TS, Hwu ET, Chen CH, Eugen-Olsen J, Hwang IS, Boisen A. Nanomechanical recognition of prognostic biomarker suPAR with DVD-ROM optical technology. NANOTECHNOLOGY 2013; 24:444011. [PMID: 24113286 DOI: 10.1088/0957-4484/24/44/444011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this work the use of a high-throughput nanomechanical detection system based on a DVD-ROM optical drive and cantilever sensors is presented for the detection of urokinase plasminogen activator receptor inflammatory biomarker (uPAR). Several large scale studies have linked elevated levels of soluble uPAR (suPAR) to infectious diseases, such as HIV, and certain types of cancer. Using hundreds of cantilevers and a DVD-based platform, cantilever deflection response from antibody-antigen recognition is investigated as a function of suPAR concentration. The goal is to provide a cheap and portable detection platform which can carry valuable prognostic information. In order to optimize the cantilever response the antibody immobilization and unspecific binding are initially characterized using quartz crystal microbalance technology. Also, the choice of antibody is explored in order to generate the largest surface stress on the cantilevers, thus increasing the signal. Using optimized experimental conditions the lowest detectable suPAR concentration is currently around 5 nM. The results reveal promising research strategies for the implementation of specific biochemical assays in a portable and high-throughput microsensor-based detection platform.
Collapse
Affiliation(s)
- Michael Bache
- Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby, DK-2800, Denmark
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
|
22
|
Rodríguez-Ruiz I, Llobera A, Vila-Planas J, Johnson DW, Gómez-Morales J, García-Ruiz JM. Analysis of the Structural Integrity of SU-8-Based Optofluidic Systems for Small-Molecule Crystallization Studies. Anal Chem 2013; 85:9678-85. [DOI: 10.1021/ac402019x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Isaac Rodríguez-Ruiz
- Laboratorio de
Estudios Cristalográficos, IACT (CSIC-UGR), Avenida de las Palmeras, 4, 18100 Armilla, Granada, Spain
| | - Andreu Llobera
- Institut
de Microelectrónica
de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Jordi Vila-Planas
- Institut
de Microelectrónica
de Barcelona (IMB-CNM, CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Donald W. Johnson
- DJ DevCorp, 490 Boston Post Road, Sudbury, Massachusetts 01776, United States
| | - Jaime Gómez-Morales
- Laboratorio de
Estudios Cristalográficos, IACT (CSIC-UGR), Avenida de las Palmeras, 4, 18100 Armilla, Granada, Spain
| | - Juan Manuel García-Ruiz
- Laboratorio de
Estudios Cristalográficos, IACT (CSIC-UGR), Avenida de las Palmeras, 4, 18100 Armilla, Granada, Spain
| |
Collapse
|
23
|
Yen YK, Lai YC, Hong WT, Pheanpanitporn Y, Chen CS, Huang LS. Electrical detection of C-reactive protein using a single free-standing, thermally controlled piezoresistive microcantilever for highly reproducible and accurate measurements. SENSORS 2013; 13:9653-68. [PMID: 23899933 PMCID: PMC3812573 DOI: 10.3390/s130809653] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 11/16/2022]
Abstract
This study demonstrates a novel method for electrical detection of C-reactive protein (CRP) as a means of identifying an infection in the body, or as a cardiovascular disease risk assay. The method uses a single free-standing, thermally controlled piezoresistive microcantilever biosensor. In a commonly used sensing arrangement of conventional dual cantilevers in the Wheatstone bridge circuit, reference and gold-coated sensing cantilevers that inherently have heterogeneous surface materials and different multilayer structures may yield independent responses to the liquid environmental changes of chemical substances, flow field and temperature, leading to unwanted signal disturbance for biosensing targets. In this study, the single free-standing microcantilever for biosensing applications is employed to resolve the dual-beam problem of individual responses in chemical solutions and, in a thermally controlled system, to maintain its sensor performance due to the sensitive temperature effect. With this type of single temperature-controlled microcantilever sensor, the electrical detection of various CRP concentrations from 1 µg/mL to 200 µg/mL was performed, which covers the clinically relevant range. Induced surface stresses were measured at between 0.25 N/m and 3.4 N/m with high reproducibility. Moreover, the binding affinity (KD) of CRP and anti-CRP interaction was found to be 18.83 ± 2.99 µg/mL, which agreed with results in previous reported studies. This biosensing technique thus proves valuable in detecting inflammation, and in cardiovascular disease risk assays.
Collapse
Affiliation(s)
- Yi-Kuang Yen
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan; E-Mails: (Y.-K.Y.); (Y.-C.L.); (W.-T.H.); (Y.P.)
| | - Yu-Cheng Lai
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan; E-Mails: (Y.-K.Y.); (Y.-C.L.); (W.-T.H.); (Y.P.)
| | - Wei-Ting Hong
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan; E-Mails: (Y.-K.Y.); (Y.-C.L.); (W.-T.H.); (Y.P.)
| | - Yotsapoom Pheanpanitporn
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan; E-Mails: (Y.-K.Y.); (Y.-C.L.); (W.-T.H.); (Y.P.)
| | - Chuin-Shan Chen
- Department of Civil Engineering, National Taiwan University, Taipei 10617, Taiwan; E-Mail:
| | - Long-Sun Huang
- Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan; E-Mails: (Y.-K.Y.); (Y.-C.L.); (W.-T.H.); (Y.P.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-2-3366-5653; Fax: +886-2-2363-9290
| |
Collapse
|
24
|
Aekbote BL, Jacak J, Schütz GJ, Csányi E, Szegletes Z, Ormos P, Kelemen L. Aminosilane-based functionalization of two-photon polymerized 3D SU-8 microstructures. Eur Polym J 2012. [DOI: 10.1016/j.eurpolymj.2012.06.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
25
|
Urwyler P, Pascual A, Kristiansen PM, Gobrecht J, Müller B, Schift H. Mechanical and chemical stability of injection-molded microcantilevers used for sensing. J Appl Polym Sci 2012. [DOI: 10.1002/app.37767] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
26
|
Høyer H, Knaapila M, Kjelstrup-Hansen J, Liu X, Helgesen G. Individual strings of conducting carbon cones and discs in a polymer matrix: Electric field-induced alignment and their use as a strain sensor. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/polb.23031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
27
|
Ingrosso C, Martin-Olmos C, Llobera A, Innocenti C, Sangregorio C, Striccoli M, Agostiano A, Voigt A, Gruetzner G, Brugger J, Perez-Murano F, Curri ML. Oxide nanocrystal based nanocomposites for fabricating photoplastic AFM probes. NANOSCALE 2011; 3:4632-4639. [PMID: 21858377 DOI: 10.1039/c1nr10487j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report on the synthesis, characterization and application of a novel nanocomposite made of a negative tone epoxy based photoresist modified with organic-capped Fe(2)O(3) nanocrystals (NCs). The mechanical properties of the nanocomposite drastically improve upon incorporation of a suitable concentration of NCs in the polymer, without deteriorating its photolithography performance. High aspect ratio 3D microstructures made of the nanocomposite have been fabricated with a uniform surface morphology and with a resolution down to few micrometres. The embedded organic-capped Fe(2)O(3) NCs drastically increase the stiffness and hardness of the epoxy based photoresist matrix, making the final material extremely interesting for manufacturing miniaturized polymer based mechanical devices and systems. In particular, the nanocomposite has been used as structural material for fabricating photoplastic Atomic Force Microscopy (AFM) probes with integrated tips showing outstanding mechanical response and high resolution imaging performance. The fabricated probes consist of straight cantilevers with low stress-gradient and high quality factors, incorporating sharp polymeric tips. They present considerably improved performance compared to pure epoxy based photoresist AFM probes, and to commercial silicon AFM probes.
Collapse
Affiliation(s)
- Chiara Ingrosso
- CNR-IPCF Sez. Bari c/o Dipartimento di Chimica, Università di Bari, via Orabona 4, Bari, 70126, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Shokuhfar A, Heydari P, Ebrahimi-Nejad S. Electrostatic excitation for the force amplification of microcantilever sensors. SENSORS 2011; 11:10129-42. [PMID: 22346633 PMCID: PMC3274275 DOI: 10.3390/s111110129] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 10/17/2011] [Accepted: 10/17/2011] [Indexed: 11/16/2022]
Abstract
This paper describes an electrostatic excited microcantilever sensor operating in static mode that is more sensitive than traditional microcantilevers. The proposed sensor comprises a simple microcantilever with electrostatic excitation ability and an optical or piezoresistive detector. Initially the microcantilever is excited by electrostatic force to near pull-in voltage. The nonlinear behavior of the microcantilever in near pull-in voltage i.e., the inverse-square relation between displacement and electrostatic force provides a novel method for force amplification. In this situation, any external load applied to the sensor will be amplified by electrostatic force leading to more displacement. We prove that the proposed microcantilever sensor can be 2 to 100 orders more sensitive compared with traditional microcantilevers sensors of the same dimensions. The results for surface stress and the free-end point force load are discussed.
Collapse
Affiliation(s)
- Ali Shokuhfar
- Advanced Materials and Nanotechnology Research Lab, Faculty of Mechanical Engineering, K.N.Toosi University of Technology, Tehran 19991-43344, Iran.
| | | | | |
Collapse
|
29
|
Zhu SE, Shabani R, Rho J, Kim Y, Hong BH, Ahn JH, Cho HJ. Graphene-based bimorph microactuators. NANO LETTERS 2011; 11:977-81. [PMID: 21280657 DOI: 10.1021/nl103618e] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A novel graphene-on-organic film fabrication method that is compatible with a batch microfabrication process was developed and used for electromechanically driven microactuators. A very thin layer of graphene sheets was monolithically integrated and the unique material characteristics of graphene including negative thermal expansion and high electrical conductivity were exploited to produce a bimorph actuation. A large displacement with rapid response was observed while maintaining the low power consumption. This enabled the successful demonstration of transparent graphene-based organic microactuators.
Collapse
Affiliation(s)
- Shou-En Zhu
- SKKU Advanced Institute of Nanotechnology (SAINT) and Center for Human Interface Nano Technology (HINT), Republic of Korea
| | | | | | | | | | | | | |
Collapse
|
30
|
Preechaburana P, Filippini D. Fabrication of monolithic 3D micro-systems. LAB ON A CHIP 2011; 11:288-295. [PMID: 21046026 DOI: 10.1039/c0lc00331j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This article describes a method and platform for fast prototyping of monolithic 3D microstructures, capable of producing arbitrary positive, negative and suspended 3D geometries, as well as sealed spaces and aligned 3D geometries using standard photoresists and few fabrication steps. Here a microfabrication method employing a mask-less micro-projection lithography platform, which co-exists on a routine fluorescence microscope, has been refined to produce a variety of 3D microstructures with up to 5 µm spatial resolutions and 10:1 aspect ratios, as well as its integration within macroscopic areas of several millimetres with up to 30 µm spatial resolutions.
Collapse
Affiliation(s)
- Pakorn Preechaburana
- Optical Devices Laboratory, Division of Applied Physics, IFM-Linköping University, S58183, Linköping, Sweden
| | | |
Collapse
|
31
|
Psoma SD, van der Wal PD, Frey O, de Rooij NF, Turner AP. A novel enzyme entrapment in SU-8 microfabricated films for glucose micro-biosensors. Biosens Bioelectron 2010; 26:1582-7. [DOI: 10.1016/j.bios.2010.07.117] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 07/17/2010] [Accepted: 07/29/2010] [Indexed: 11/27/2022]
|
32
|
Jasson V, Jacxsens L, Luning P, Rajkovic A, Uyttendaele M. Alternative microbial methods: An overview and selection criteria. Food Microbiol 2010; 27:710-30. [DOI: 10.1016/j.fm.2010.04.008] [Citation(s) in RCA: 193] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 04/12/2010] [Accepted: 04/20/2010] [Indexed: 11/25/2022]
|
33
|
Shadpour H, Allbritton NL. In situ roughening of polymeric microstructures. ACS APPLIED MATERIALS & INTERFACES 2010; 2:1086-93. [PMID: 20423129 PMCID: PMC2861798 DOI: 10.1021/am900860s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
A method to perform in situ roughening of arrays of microstructures weakly adherent to an underlying substrate was presented. SU8, 1002F, and polydimethylsiloxane (PDMS) microstructures were roughened by polishing with a particle slurry. The roughness and the percentage of dislodged or damaged microstructures was evaluated as a function of the roughening time for both SU8 and 1002F structures. A maximal RMS roughness of 7-18 nm for the surfaces was obtained within 15-30 s of polishing with the slurry. This represented a 4-9 fold increase in surface roughness relative to that of the native surface. Less than 0.8% of the microstructures on the array were removed or damaged after 5 min of polishing. Native and roughened arrays were assessed for their ability to support fibronectin adhesion and cell attachment and growth. The quantity of adherent fibronectin was increased on roughened arrays by two-fold over that on native arrays. Cell adhesion to the roughened surfaces was also increased compared to native surfaces. Surface roughening with the particle slurry also improved the ability to stamp molecules onto the substrate during microcontact printing. Roughening both the PDMS stamp and substrate resulted in up to a 20-fold improvement in the transfer of BSA-Alexa Fluor 647 from the stamp to the substrate. Thus roughening of micrometer-scale surfaces with a particle slurry increased the adhesion of biomolecules as well as cells to microstructures with little to no damage to largescale arrays of the structures.
Collapse
Affiliation(s)
- Hamed Shadpour
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Nancy L. Allbritton
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, USA
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, 27599, North Carolina, USA, and North Carolina State University, Raleigh, North Carolina 27695, USA
| |
Collapse
|
34
|
Arroyo-Hernández M, Tamayo J, Costa-Krämer JL. Stress and DNA assembly differences on cantilevers gold coated by resistive and e-beam evaporation techniques. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:10633-10638. [PMID: 19694416 DOI: 10.1021/la900696f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Changes in the sign of differential surface stress of gold-coated cantilevers produced by thiol-derivatized single-stranded DNA immobilization are observed, depending on the method used to deposit the gold. While the DNA immobilization on e-beam gold-coated cantilevers produces a compressive differential surface stress in the metallic layer, the opposite is observed for resistively coated cantilevers under the same immobilization conditions. The gold films exhibit quite a similar morphology, and the immobilization differences seem to be related to the charge state of the metallic layer surface. This in turn produces a different distribution of the orientation of the DNA strands on the gold layer. A tentative explanation for the observed effect is proposed.
Collapse
Affiliation(s)
- M Arroyo-Hernández
- Instituto de Microelectrónica de Madrid, IMM-CNM-CSIC, Isaac Newton 8, PTM, 28760 Tres Cantos, Madrid, Spain.
| | | | | |
Collapse
|
35
|
Ingrosso C, Striccoli M, Agostiano A, Sardella E, Keller S, Blagoi G, Boisen A, Curri M. Surface Functionalization of Micro Mechanical Cantilever Sensors by Organic Capped TiO2 and Fe2O3 Nanocrystals. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.proche.2009.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
36
|
Luchini A, Longo C, Espina V, Petricoin EF, Liotta LA. Nanoparticle technology: Addressing the fundamental roadblocks to protein biomarker discovery. JOURNAL OF MATERIALS CHEMISTRY 2009; 19:5071-5077. [PMID: 20585471 PMCID: PMC2888266 DOI: 10.1039/b822264a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The incorporation of affinity baits into N-isopropylacrylamide-hydrogel-based nanoparticles offers a novel technology that addresses the major analytical challenges of disease biomarker discovery. In solution in complex biologic fluids (e.g. blood or urine), core-shell bait-containing nanoparticles can perform three functions in one step: (a) sieve molecules according to size, (b) sequestrate and concentrate target analytes, and (c) protect analytes from degradation.
Collapse
|
37
|
Deflection, frequency, and stress characteristics of rectangular, triangular, and step profile microcantilevers for biosensors. SENSORS 2009; 9:6046-57. [PMID: 22454571 PMCID: PMC3312429 DOI: 10.3390/s90806046] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 11/16/2022]
Abstract
This study presents the deflection, resonant frequency and stress results of rectangular, triangular, and step profile microcantilevers subject to surface stress. These cantilevers can be used as the sensing element in microcantilever biosensors. To increase the overall sensitivity of microcantilever biosensors, both the deflection and the resonant frequency of the cantilever should be increased. The effect of the cantilever profile change and the cantilever cross-section shape change is first investigated separately and then together. A finite element code ANSYS Multiphysics is used and solid finite elements cantilever models are solved. A surface stress of 0.05 N/m was applied to the top surface of the cantilevers. The cantilevers are made of silicon with elastic modulus 130 GPa and Poisson’s ratio 0.28. To show the conformity of this study, the numerical results are compared against their analytical ones. Results show that triangular and step cantilevers have better deflection and frequency characteristics than rectangular ones.
Collapse
|
38
|
Comparison between Deflection and Vibration Characteristics of Rectangular and Trapezoidal profile Microcantilevers. SENSORS 2009; 9:2706-18. [PMID: 22574041 PMCID: PMC3348801 DOI: 10.3390/s90402706] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 04/10/2009] [Accepted: 04/15/2009] [Indexed: 11/17/2022]
Abstract
Arrays of microcantilevers are increasingly being used as physical, biological, and chemical sensors in various applications. To improve the sensitivity of microcantilever sensors, this study analyses and compares the deflection and vibration characteristics of rectangular and trapezoidal profile microcantilevers. Three models of each profile are investigated. The cantilevers are analyzed for maximum deflection, fundamental resonant frequency and maximum stress. The surface stress is modelled as in-plane tensile force applied on the top edge of the microcantilevers. A commercial finite element analysis software ANSYS is used to analyze the designs. Results show paddled trapezoidal profile microcantilevers have better sensitivity.
Collapse
|
39
|
Ansari MZ, Cho C. A Study on Increasing Sensitivity of Rectangular Microcantilevers Used in Biosensors. SENSORS 2008; 8:7530-7544. [PMID: 27873943 PMCID: PMC3787459 DOI: 10.3390/s8117530] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Revised: 11/10/2008] [Accepted: 11/10/2008] [Indexed: 12/02/2022]
Abstract
This study proposes a new microcantilever design with a rectangular hole at the fixed end of the cantilever that is more sensitive than conventional ones. A commercial finite element analysis software ANSYS is used to analyze it. The Stoney equation is first used to calculate the surface stress induced moment, and then applied to the microcantilever free end to produce deflection. The stress analysis of the proposed and conventional designs is performed, followed by dynamic analysis of the proposed design. We found that the Sader equation is more accurate than Stoney in predicting cantilever deflections, and that for increasing the sensitivity of a microcantilever biosensor increasing the cantilever thickness is more practical.
Collapse
Affiliation(s)
- Mohd Zahid Ansari
- Department of Mechanical Engineering, Inha University, 253 Yonghyun-dong, Nam-Ku, Incheon, 402-751 Republic of Korea.
| | - Chongdu Cho
- Department of Mechanical Engineering, Inha University, 253 Yonghyun-dong, Nam-Ku, Incheon, 402-751 Republic of Korea.
| |
Collapse
|