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Anand G, Safaripour S, Snoeyink C. Anomalous, dielectrophoretic transport of molecules in non-electrolytes. J Sep Sci 2024; 47:e2300719. [PMID: 38066389 DOI: 10.1002/jssc.202300719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/08/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024]
Abstract
The electric field (E-field) dielectric polarization-based separations mechanism represents a novel method for separating solutions at small length scales. An E-field gradient with a maximum strength of 0.4 MV/m applied across a 10 μm deep channel is shown to increase the concentration inside the low E-field region by ≈ 40% relative to the high E-field region. This concentration change is two orders of magnitude higher than the estimated change predicted using the classical equilibrium thermodynamics for the same E-field. The deviation between the predicted and the experimental results suggests that the change in volumetric E-field energy with solute concentration is insufficient to explain this phenomenon. The study also explores the effect of varying strength of E-field and frequency of supplied voltage on the dielectric polarization-based separation efficiency. While the increase in the former increases the separation efficiency, the increase in the latter reduces the degree of concentration change due to ineffective charging of the electrodes.
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Affiliation(s)
- Gaurav Anand
- Department of Mechanical and Aerospace Engineering, University at Buffalo, Buffalo, New York, USA
| | - Samira Safaripour
- Department of Mechanical and Aerospace Engineering, University at Buffalo, Buffalo, New York, USA
| | - Craig Snoeyink
- Department of Mechanical and Aerospace Engineering, University at Buffalo, Buffalo, New York, USA
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2
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Pil-Ali A, Adnani S, Karim KS. Self-aligned multi-layer X-ray absorption grating using large-area fabrication methods for X-ray phase-contrast imaging. Sci Rep 2023; 13:2508. [PMID: 36781907 PMCID: PMC9925796 DOI: 10.1038/s41598-023-29580-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 02/07/2023] [Indexed: 02/15/2023] Open
Abstract
X-ray phase-contrast (XPCi) imaging methods are an emerging medical imaging approach that provide significantly better soft tissue contrast and could function as a viable extension to conventional X-ray, CT, and even some MRI. Absorption gratings play a central role in grating-based XPCi systems, especially because they enable the acquisition of three images in a single exposure: transmission, refraction, and dark-field. An impediment to commercial development and adoption of XPCi imaging systems is the lack of large area, high aspect ratio absorption gratings. Grating technology development, primarily due to technological limitations, has lagged system development and today prevents the scaling up of XPCi system into a footprint and price point acceptable to the medical market. In this work, we report on a self-aligned multi-layer grating fabrication process that can enable large-area X-ray absorption gratings with micron-scale feature sizes. We leverage large-area fabrication techniques commonly employed by the thin-film transistor (TFT) display industry. Conventional ITO-on-glass substrates are used with a patterned film of Cr/Au/Cr that serves as a self-aligned lithography mask for backside exposure. Commonly available SU-8 photoresist is patterned using the backside exposure mask followed by an electroplating step to fill the gaps in the SU-8 with X-ray attenuating material. Consequently, the electroplated patterned material acts as a self-aligned photomask for subsequent SU-8 layer patterning and so forth. The repeatability of the reported process makes it suitable for achieving higher aspect ratio structures and is advantageous over previously reported X-ray LIGA approaches. A prototype three-layer grating, with a thickness of around [Formula: see text], having a visibility of 0.28 at [Formula: see text] with a [Formula: see text] active area was fabricated on a 4-inch glass substrate and demonstrated by modifying a commercially available 3D propagation-based XPCi Microscope. The scalable and cost-effective approach to build larger area X-ray gratings reported in this work can help expedite the commercial development and adoption of previously reported Talbot-Lau, speckle-tracking, as well as coded-aperture XPCi systems for large-area clinical and industrial applications.
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Affiliation(s)
- Abdollah Pil-Ali
- Department of Electrical and Computer Engineering, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L3G1, Canada. .,Centre for Bioengineering and Biotechnology, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L3G1, Canada.
| | - Sahar Adnani
- grid.46078.3d0000 0000 8644 1405Department of Electrical and Computer Engineering, University of Waterloo, 200 University Ave W, Waterloo, ON N2L3G1 Canada ,grid.46078.3d0000 0000 8644 1405Centre for Bioengineering and Biotechnology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L3G1 Canada
| | - Karim S. Karim
- grid.46078.3d0000 0000 8644 1405Department of Electrical and Computer Engineering, University of Waterloo, 200 University Ave W, Waterloo, ON N2L3G1 Canada ,grid.46078.3d0000 0000 8644 1405Centre for Bioengineering and Biotechnology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L3G1 Canada
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3
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Tang Y, Kim ES. Simple sacrificial-layer-free microfabrication processes for air-cavity Fresnel acoustic lenses (ACFALs) with improved focusing performance. MICROSYSTEMS & NANOENGINEERING 2022; 8:75. [PMID: 35812805 PMCID: PMC9256634 DOI: 10.1038/s41378-022-00407-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 04/23/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
Focused ultrasound (FUS) is a powerful tool widely used in biomedical therapy and imaging as well as in sensors and actuators. Conventional focusing techniques based on curved surfaces, metamaterial structures, and multielement phased arrays either present difficulties in massively parallel manufacturing with high precision or require complex drive electronics to operate. These difficulties have been addressed by microfabricated self-focusing acoustic transducers (SFATs) with Parylene air-cavity Fresnel acoustic lenses (ACFALs), which require a time-demanding step in removing the sacrificial layer. This paper presents three new and improved types of ACFALs based on polydimethylsiloxane (PDMS), an SU-8/PDMS bilayer, and SU-8, which are manufactured through simple sacrificial-layer-free microfabrication processes that are two to four times faster than that for the Parylene ACFALs. Moreover, by studying the effect of the lens thickness on the acoustic transmittance through the lens, the performance of the transducers has been optimized with improved thickness control techniques developed for PDMS and SU-8. As a result, the measured power transfer efficiency (PTE) and peak output acoustic pressure are up to 2.0 and 1.8 times higher than those of the Parylene ACFALs, respectively. The simple microfabrication techniques described in this paper are useful for manufacturing not only high-performance ACFALs but also other miniaturized devices with hollow or suspended structures for microfluidic and optical applications.
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Affiliation(s)
- Yongkui Tang
- Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA 90089-0271 USA
| | - Eun Sok Kim
- Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA 90089-0271 USA
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4
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Cong H, Zhang N. Perspectives in translating microfluidic devices from laboratory prototyping into scale-up production. BIOMICROFLUIDICS 2022; 16:021301. [PMID: 35350441 PMCID: PMC8933055 DOI: 10.1063/5.0079045] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/23/2022] [Indexed: 05/05/2023]
Abstract
Transforming lab research into a sustainable business is becoming a trend in the microfluidic field. However, there are various challenges during the translation process due to the gaps between academia and industry, especially from laboratory prototyping to industrial scale-up production, which is critical for potential commercialization. In this Perspective, based on our experience in collaboration with stakeholders, e.g., biologists, microfluidic engineers, diagnostic specialists, and manufacturers, we aim to share our understanding of the manufacturing process chain of microfluidic cartridge from concept development and laboratory prototyping to scale-up production, where the scale-up production of commercial microfluidic cartridges is highlighted. Four suggestions from the aspect of cartridge design for manufacturing, professional involvement, material selection, and standardization are provided in order to help scientists from the laboratory to bring their innovations into pre-clinical, clinical, and mass production and improve the manufacturability of laboratory prototypes toward commercialization.
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Affiliation(s)
- Hengji Cong
- Centre of Micro/Nano Manufacturing Technology (MNMT-Dublin), School of Mechanical & Materials Engineering, University College Dublin, Dublin 4, Ireland
| | - Nan Zhang
- Author to whom correspondence should be addressed:
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5
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Calm YM, D'Imperio L, Nesbitt NT, Merlo JM, Rose AH, Yang C, Kempa K, Burns MJ, Naughton MJ. Optical confinement in the nanocoax: coupling to the fundamental TEM-like mode. OPTICS EXPRESS 2020; 28:32152-32164. [PMID: 33115178 DOI: 10.1364/oe.402723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 09/11/2020] [Indexed: 06/11/2023]
Abstract
The nanoscale coaxial cable (nanocoax) has demonstrated optical confinement in the visible and the near infrared. We report on a novel nanofabrication process which yields optically addressable, sub-µm diameter, and high aspect ratio metal-insulator-metal nanocoaxes made by atomic layer deposition of Pt and Al2O3. We observe sub-diffraction-limited optical transmission via the fundamental, TEM-like mode by excitation with a radially polarized optical vortex beam. Our experimental results are based on interrogation with a polarimetric imager. Finite element method numerical simulations support these results, and their uniaxial symmetry was exploited to model taper geometries with both an electrically large volume, (15λ)3, and a nanoscopic exit aperture, (λ/200)2.
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Lobo‐Júnior EO, Chagas CLS, Duarte LC, Cardoso TMG, Souza FR, Lima RS, Coltro WKT. Inexpensive and nonconventional fabrication of microfluidic devices in PMMA based on a soft‐embossing protocol. Electrophoresis 2020; 41:1641-1650. [DOI: 10.1002/elps.202000131] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/06/2022]
Affiliation(s)
| | - Cyro L. S. Chagas
- Instituto de Química Universidade Federal de Goiás Goiânia GO Brazil
- Instituto de Química Universidade de Brasília Brasília DF Brazil
| | - Lucas C. Duarte
- Instituto de Química Universidade Federal de Goiás Goiânia GO Brazil
| | | | - Fabrício R. Souza
- Instituto de Química Universidade Federal de Goiás Goiânia GO Brazil
| | - Renato S. Lima
- Laboratório Nacional de Nanotecnologia Centro Nacional de Pesquisa em Energia e Materiais Campinas SP Brazil
- Instituto de Química Universidade Estadual de Campinas Campinas SP Brazil
| | - Wendell K. T. Coltro
- Instituto de Química Universidade Federal de Goiás Goiânia GO Brazil
- Instituto Nacional de Ciência e Tecnologia de Bioanalítica Campinas SP Brazil
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7
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Surface wettability and stability of chemically modified silicon, glass and polymeric surfaces via room temperature chemical vapor deposition. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.03.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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8
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Anoop V, Subramani S, Jaisankar SN, Sohini C, Mary NL. Mechanical, dielectric, and thermal properties of polydimethylsiloxane/polysilsesquioxane nanocomposite for sealant application. J Appl Polym Sci 2018. [DOI: 10.1002/app.47228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- V. Anoop
- Department of Chemistry; Stella Maris College; Chennai, 600086 Tamil Nadu India
| | - S. Subramani
- Anabond Limited; Chennai, 600096 Tamil Nadu India
| | - S. N. Jaisankar
- Polymer Science and Technology Division; Central Leather Research Institute; Chennai, 600020 Tamil Nadu India
| | - C. Sohini
- Department of Chemistry; Stella Maris College; Chennai, 600086 Tamil Nadu India
| | - N. L. Mary
- Department of Chemistry; Stella Maris College; Chennai, 600086 Tamil Nadu India
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9
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Lobo-Júnior EO, L S Chagas C, Coltro WKT. Determination of inorganic cations in biological fluids using a hybrid capillary electrophoresis device coupled with contactless conductivity detection. J Sep Sci 2018; 41:3310-3317. [PMID: 29956462 DOI: 10.1002/jssc.201800403] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/19/2018] [Accepted: 06/20/2018] [Indexed: 12/22/2022]
Abstract
We describe the assembly of a hybrid electrophoresis device that contains fused silica capillaries interconnected to a microfabricated interface in a cross format for the determination of inorganic cations in biological samples. The sample transport in the proposed hybrid device was performed under gated injection mode and the separations were monitored with a capacitively coupled contactless conductivity detector. The capillary extremities were inserted into polypropylene tubes to create solution reservoirs. Sensing electrodes were produced using stainless-steel hypodermic needles previously cut with 2.0 mm length. The running composition and injection time were optimized and the best results were found using 50 mmol/L lactic acid, 20 mmol/L histidine and 3 mmol/L 18-crown-6 ether, and an electrokinetic injection time of 15 s. The separation of six inorganic cations was achieved with baseline resolution, and efficiencies were between 9.1 × 103 and 5.4 × 104 plates/m. The proposed hybrid device was explored for determining the concentration levels of inorganic cations in urine, saliva, and tear samples, employing Li+ as an internal standard. The achieved results were in good agreement with the data reported in the literature. The reliability of the proposed method ranged from 93 to 98%, thus suggesting satisfactory accuracy for bioanalytical applications.
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Affiliation(s)
| | - Cyro L S Chagas
- Instituto de Química, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Wendell K T Coltro
- Instituto de Química, Universidade Federal de Goiás, Goiânia, GO, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica, Campinas, SP, Brazil
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10
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Pandey CM, Augustine S, Kumar S, Kumar S, Nara S, Srivastava S, Malhotra BD. Microfluidics Based Point-of-Care Diagnostics. Biotechnol J 2017; 13. [DOI: 10.1002/biot.201700047] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 11/06/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Chandra M. Pandey
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
- Department of Applied Chemistry; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Shine Augustine
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Saurabh Kumar
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Suveen Kumar
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Sharda Nara
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Saurabh Srivastava
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
- Department of Applied Physics; Delhi Technological University; Shahbad Daulatpur Delhi India
| | - Bansi D. Malhotra
- Department of Biotechnology; Delhi Technological University; Shahbad Daulatpur Delhi India
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11
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Shimizu FM, Todão FR, Gobbi AL, Oliveira ON, Garcia CD, Lima RS. Functionalization-Free Microfluidic Electronic Tongue Based on a Single Response. ACS Sens 2017; 2:1027-1034. [PMID: 28750534 DOI: 10.1021/acssensors.7b00302] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Electronic tongues (e-tongues) are promising analytical devices for a variety of applications to address the challenges of quality control in water monitoring and industries of foods, beverages, and pharmaceuticals. A crucial drawback in the current e-tongues is the need to recalibrate the device when one or more sensing units (usually with modified surface) are replaced. Another downside is the necessity to perform subsequent surface modifications and analyses to each of the diverse sensing units, undermining the simplicity and velocity of the method. These features have prevented widespread commercial use of the e-tongues. In this paper, we introduce a microfluidic e-tongue that overcomes all such limitations. The key principle of global selectivity of the e-tongue was achieved by recording only a single response, namely, the equivalent admittance spectrum of an association of resistors in parallel. Such resistors consisted of five nonfunctionalized stainless steel microwires (sensing units), which were short-circuited and coated with gold, platinum, nickel, iron, and aluminum oxide films. The microwires were inserted in a chip composed of a single piece of polydimethylsiloxane (PDMS). Using impedance spectroscopy, the e-tongue was successfully applied in classification of basic tastes at a concentration below the threshold for the human tongue. In addition, our chip allowed the distinction of various chemicals used in oil industry. Finally, our cleanroom-free prototyping allows the mass production of chips with easily replaceable and reproducible sensing units. Hence, one can now envisage the widespread dissemination of e-tongues with fast and reproducible data.
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Affiliation(s)
- Flavio M. Shimizu
- Instituto
de Física de São Carlos, Universidade de São Paulo, São
Carlos, São Paulo 13560-970, Brasil
| | - Fagner R. Todão
- Laboratório
Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
| | - Angelo L. Gobbi
- Laboratório
Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
| | - Osvaldo N. Oliveira
- Instituto
de Física de São Carlos, Universidade de São Paulo, São
Carlos, São Paulo 13560-970, Brasil
| | - Carlos D. Garcia
- Department
of Chemistry, Clemson University, 219 Hunter Laboratories, Clemson, South Carolina 29634, United States
| | - Renato S. Lima
- Laboratório
Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
- Instituto
de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, Brasil
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12
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Shiroma LS, Oliveira AF, Lobo-Júnior EO, Coltro WK, Gobbi AL, de La Torre LG, Lima RS. High adhesion strength and hybrid irreversible/reversible full-PDMS microfluidic chips. Anal Chim Acta 2017; 951:116-123. [DOI: 10.1016/j.aca.2016.11.048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 11/17/2016] [Accepted: 11/18/2016] [Indexed: 10/20/2022]
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13
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Teixeira CA, Giordano GF, Beltrame MB, Vieira LCS, Gobbi AL, Lima RS. Renewable Solid Electrodes in Microfluidics: Recovering the Electrochemical Activity without Treating the Surface. Anal Chem 2016; 88:11199-11206. [DOI: 10.1021/acs.analchem.6b03453] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Carlos A. Teixeira
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
- Instituto
de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, Brasil
| | - Gabriela F. Giordano
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
- Instituto
de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, Brasil
| | - Maisa B. Beltrame
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
| | - Luis C. S. Vieira
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
| | - Angelo L. Gobbi
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
| | - Renato S. Lima
- Laboratório
de Microfabricação, Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brasil
- Instituto
de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, Brasil
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14
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Turbulence in microfluidics: Cleanroom-free, fast, solventless, and bondless fabrication and application in high throughput liquid-liquid extraction. Anal Chim Acta 2016; 940:73-83. [DOI: 10.1016/j.aca.2016.08.052] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 08/27/2016] [Accepted: 08/29/2016] [Indexed: 11/13/2022]
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15
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Self-regenerating and hybrid irreversible/reversible PDMS microfluidic devices. Sci Rep 2016; 6:26032. [PMID: 27181918 PMCID: PMC4867595 DOI: 10.1038/srep26032] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 04/25/2016] [Indexed: 11/08/2022] Open
Abstract
This paper outlines a straightforward, fast, and low-cost method to fabricate polydimethylsiloxane (PDMS) chips. Termed sandwich bonding (SWB), this method requires only a laboratory oven. Initially, SWB relies on the reversible bonding of a coverslip over PDMS channels. The coverslip is smaller than the substrate, leaving a border around the substrate exposed. Subsequently, a liquid composed of PDMS monomers and a curing agent is poured onto the structure. Finally, the cover is cured. We focused on PDMS/glass chips because of their key advantages in microfluidics. Despite its simplicity, this method created high-performance microfluidic channels. Such structures featured self-regeneration after leakages and hybrid irreversible/reversible behavior. The reversible nature was achieved by removing the cover of PDMS with acetone. Thus, the PDMS substrate and glass coverslip could be detached for reuse. These abilities are essential in the stages of research and development. Additionally, SWB avoids the use of surface oxidation, half-cured PDMS as an adhesive, and surface chemical modification. As a consequence, SWB allows surface modifications before the bonding, a long time for alignment, the enclosure of sub-micron channels, and the prototyping of hybrid devices. Here, the technique was successfully applied to bond PDMS to Au and Al.
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