1
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Panda K, Mittapally R, Reddy P, Yadlapalli S, Meyhofer E. Micro-kelvin temperature-stable system for biocalorimetry applications. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:034902. [PMID: 38446002 PMCID: PMC10919956 DOI: 10.1063/5.0188285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/10/2024] [Indexed: 03/07/2024]
Abstract
Achieving micro-kelvin (µK) temperature stability is critical for many calorimetric applications. For example, sub-nanowatt resolution biocalorimetry requires stabilization of the temperature of the calorimeter to µK levels. Here, we describe how µK temperature stability can be accomplished in a prototypical calorimetric system consisting of two nested shields and a suspended capillary tube, which is well suited for biocalorimetry applications. Specifically, we show that by employing nested shields with µTorr-levels of vacuum in the space between them as well as precise feedback control of the temperature of the shields (performed using high-resolution temperature sensors), the effect of ambient temperature fluctuations on the inner shield and the capillary tube can be attenuated by ∼100 dB. We also show that this attenuation is key to achieving temperature stabilities within ±1 and ±3 µK (amplitude of oscillations) for the inner shield and the capillary tube sensor, respectively, measured in a bandwidth of 1 mHz over a period of 10 h at room temperature (∼20.9 ± 0.2 °C). We expect that the methods described here will play a key role in advancing biocalorimetry.
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Affiliation(s)
- Kanishka Panda
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Rohith Mittapally
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Pramod Reddy
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Swathi Yadlapalli
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Edgar Meyhofer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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2
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Ko J, Lee BJ, Lee J. Advanced operation of heated fluidic resonators via mechanical and thermal loss reduction in vacuum. MICROSYSTEMS & NANOENGINEERING 2023; 9:127. [PMID: 37829159 PMCID: PMC10564801 DOI: 10.1038/s41378-023-00575-3] [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: 03/25/2023] [Revised: 06/06/2023] [Accepted: 07/04/2023] [Indexed: 10/14/2023]
Abstract
For simultaneous and quantitative thermophysical measurements of ultrasmall liquid volumes, we have recently developed and reported heated fluidic resonators (HFRs). In this paper, we improve the precision of HFRs in a vacuum by significantly reducing the thermal loss around the sensing element. A vacuum chamber with optical, electrical, and microfluidic access is custom-built to decrease the convection loss by two orders of magnitude under 10-4 mbar conditions. As a result, the measurement sensitivities for thermal conductivity and specific heat capacity are increased by 4.1 and 1.6 times, respectively. When differentiating between deionized water (H2O) and heavy water (D2O) with similar thermophysical properties and ~10% different mass densities, the signal-to-noise ratio (property differences over standard error) for H2O and D2O is increased by 9 and 5 times for thermal conductivity and specific heat capacity, respectively.
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Affiliation(s)
- Juhee Ko
- Department of Mechanical Engineering, Center for Extreme Thermal Physics and Manufacturing, Korea Advanced Institute of Science and Technology (KAIST), 34141 Daejeon, Korea
| | - Bong Jae Lee
- Department of Mechanical Engineering, Center for Extreme Thermal Physics and Manufacturing, Korea Advanced Institute of Science and Technology (KAIST), 34141 Daejeon, Korea
| | - Jungchul Lee
- Department of Mechanical Engineering, Center for Extreme Thermal Physics and Manufacturing, Korea Advanced Institute of Science and Technology (KAIST), 34141 Daejeon, Korea
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3
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Vehusheia SLK, Roman C, Braissant O, Arnoldini M, Hierold C. Enabling direct microcalorimetric measurement of metabolic activity and exothermic reactions onto microfluidic platforms via heat flux sensor integration. MICROSYSTEMS & NANOENGINEERING 2023; 9:56. [PMID: 37180454 PMCID: PMC10169645 DOI: 10.1038/s41378-023-00525-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 02/13/2023] [Indexed: 05/16/2023]
Abstract
All biological processes use or produce heat. Traditional microcalorimeters have been utilized to study the metabolic heat output of living organisms and heat production of exothermic chemical processes. Current advances in microfabrication have made possible the miniaturization of commercial microcalorimeters, resulting in a few studies on the metabolic activity of cells at the microscale in microfluidic chips. Here we present a new, versatile, and robust microcalorimetric differential design based on the integration of heat flux sensors on top of microfluidic channels. We show the design, modeling, calibration, and experimental verification of this system by utilizing Escherichia coli growth and the exothermic base catalyzed hydrolysis of methyl paraben as use cases. The system consists of a Polydimethylsiloxane based flow-through microfluidic chip with two 46 µl chambers and two integrated heat flux sensors. The differential compensation of thermal power measurements allows for the measurement of bacterial growth with a limit of detection of 1707 W/m3, corresponding to 0.021OD (2 ∙ 107 bacteria). We also extracted the thermal power of a single Escherichia coli of between 1.3 and 4.5 pW, comparable to values measured by industrial microcalorimeters. Our system opens the possibility for expanding already existing microfluidic systems, such as drug testing lab-on-chip platforms, with measurements of metabolic changes of cell populations in form of heat output, without modifying the analyte and minimal interference with the microfluidic channel itself.
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Affiliation(s)
- Signe L. K. Vehusheia
- Micro and Nanosystems, Department of Mechanical and Process Engineering, ETH Zurich, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Cosmin Roman
- Micro and Nanosystems, Department of Mechanical and Process Engineering, ETH Zurich, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Olivier Braissant
- Center of Biomechanics and Biocalorimetry, Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167C, 4123 Allschwil, Switzerland
| | - Markus Arnoldini
- Laboratory for Food Immunology, Department of Health Sciences and Technology, ETH Zurich, Otto-Stern-Weg 3, 8093 Zurich, Switzerland
| | - Christofer Hierold
- Micro and Nanosystems, Department of Mechanical and Process Engineering, ETH Zurich, Tannenstrasse 3, 8092 Zurich, Switzerland
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4
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Sano H, Kazoe Y, Ohta R, Shimizu H, Morikawa K, Kitamori T. Nanofluidic analytical system integrated with nanochannel open/close valves for enzyme-linked immunosorbent assay. LAB ON A CHIP 2023; 23:727-736. [PMID: 36484269 DOI: 10.1039/d2lc00881e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
There have been significant advances in the field of nanofluidics, and novel technologies such as single-cell analysis have been demonstrated. Despite the evident advantages of nanofluidics, fluid control in nanochannels for complicated analyses is extremely difficult because the fluids are currently manipulated by maintaining the balance of driving pressure. To address this issue, the use of valves will be essential. Our group previously developed a nanochannel open/close valve utilizing glass deformation, but this has not yet been integrated into nanofluidic devices for analytical applications. In the present study, a nanofluidic analytical system integrated with multiple nanochannel open/close valves was developed. This system consists of eight pneumatic pumps, seven nanochannel open/close valves combined with piezoelectric actuators, and an ultra-high sensitivity detector for non-fluorescent molecules. For simultaneous actuation of multiple valves, a device holder was designed that prevented deformation of the entire device caused by operating the valves. A system was subsequently devised to align each valve and actuator with a precision of better than 20 μm to permit the operation of valves. The developed analytical system was verified by analyzing IL-6 molecules using an enzyme-linked immunosorbent assay. Fluid operations such as sample injection, pL-level aliquot sampling and flow switching were accomplished in this device simply by opening/closing specific valves, and a sample consisting of approximately 1500 IL-6 molecules was successfully detected. This study is expected to significantly improve the usability of nanofluidic analytical devices and lead to the realization of sophisticated analytical techniques such as single-cell proteomics.
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Affiliation(s)
- Hiroki Sano
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Yutaka Kazoe
- Department of System Design Engineering, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama, Kanagawa 223-8522, Japan.
| | - Ryoichi Ohta
- Collaborative Research Organization for Micro and Nano Multifunctional Devices, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Hisashi Shimizu
- Collaborative Research Organization for Micro and Nano Multifunctional Devices, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Kyojiro Morikawa
- Institute of Nanoengineering and Microsystems, Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 300044, Taiwan.
- Collaborative Research Organization for Micro and Nano Multifunctional Devices, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Takehiko Kitamori
- Institute of Nanoengineering and Microsystems, Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 300044, Taiwan.
- Collaborative Research Organization for Micro and Nano Multifunctional Devices, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
- Department of Biomedical Engineering, Faculty of Engineering, Lund University, 221 00 Lund, Sweden
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5
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Shupenev AE, Melnik SL, Korshunov IS, Karpoukhin SD, Sazonkin SG, Grigor’yants AG. Growth Features of Bi 2Te 3Sb 1.5 Films on Polyimide Substrates Obtained by Pulsed Laser Deposition. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8993. [PMID: 36556799 PMCID: PMC9788408 DOI: 10.3390/ma15248993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Thermoelectric materials in the form of thin films are used to create a wide variety of sensors and devices. The efficiency of these devices depends on the quality and efficiency of the thermoelectric materials obtained in the form of thin films. Earlier, we demonstrated that it is possible to obtain high-performance Bi2Te3Sb1.5 films less than 1 μm thick on polyimide substrates by using the PLD method, and determined optimal growth conditions. In the current work, the relationship between growth conditions and droplet fraction on the surface, microstructure, grain size, film thickness and chemical composition was studied. A power factor of 5.25 μW/cm×K2 was achieved with the reduction of droplet fraction on the film surface to 0.57%. The dependencies of the film thickness were studied, and the effect of the thickness on the efficiency of the material is shown. The general trend in the growth dynamics for Bi2Te3Sb1.5 films we obtained is the reduction of crystalline size with Pressure-Temperature (PT) criterion. The results of our work also show the possibility of a significant reduction of droplet phase with simultaneous management of crystalline features and thermoelectric efficiency of Bi2Te3Sb1.5 films grown on polyimide substrates by varying growth conditions.
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Affiliation(s)
- Alexander E. Shupenev
- Department of Laser Technology in Engineering, Bauman Moscow State Technical University, 105005 Moscow, Russia
| | - Svetlana L. Melnik
- Department of Laser Technology in Engineering, Bauman Moscow State Technical University, 105005 Moscow, Russia
| | - Ivan S. Korshunov
- Department of Laser Technology in Engineering, Bauman Moscow State Technical University, 105005 Moscow, Russia
| | - Sergey D. Karpoukhin
- Department of Materials Science, Bauman Moscow State Technical University, 105005 Moscow, Russia
| | - Stanislav G. Sazonkin
- Scientific and Educational Center “Photonics and IR Technology”, Bauman Moscow State Technical University, 105005 Moscow, Russia
| | - Alexander G. Grigor’yants
- Department of Laser Technology in Engineering, Bauman Moscow State Technical University, 105005 Moscow, Russia
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6
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Odarchenko Y, Kaźmierczak-Bałata A, Bodzenta J, Ferrari E, Soloviev M. AC/DC Thermal Nano-Analyzer Compatible with Bulk Liquid Measurements. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3799. [PMID: 36364575 PMCID: PMC9655476 DOI: 10.3390/nano12213799] [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: 07/31/2022] [Revised: 10/16/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Nanocalorimetry, or thermal nano-analysis, is a powerful tool for fast thermal processing and thermodynamic analysis of materials at the nanoscale. Despite multiple reports of successful applications in the material sciences to study phase transitions in metals and polymers, thermodynamic analysis of biological systems in their natural microenvironment has not been achieved yet. Simply scaling down traditional calorimetric techniques, although beneficial for material sciences, is not always appropriate for biological objects, which cannot be removed out of their native biological environment or be miniaturized to suit instrument limitations. Thermal analysis at micro- or nano-scale immersed in bulk liquid media has not yet been possible. Here, we report an AC/DC modulated thermal nano-analyzer capable of detecting nanogram quantities of material in bulk liquids. The detection principle used in our custom-build instrument utilizes localized heat waves, which under certain conditions confine the measurement area to the surface layer of the sample in the close vicinity of the sensing element. To illustrate the sensitivity and quantitative capabilities of the instrument we used model materials with detectable phase transitions. Here, we report ca. 106 improvement in the thermal analysis sensitivity over a traditional DSC instrument. Interestingly, fundamental thermal properties of the material can be determined independently from heat flow in DC (direct current) mode, by using the AC (alternating current) component of the modulated heat in AC/DC mode. The thermal high-frequency AC modulation mode might be especially useful for investigating thermal transitions on the surface of material, because of the ability to control the depth of penetration of AC-modulated heat and hence the depth of thermal sensing. The high-frequency AC mode might potentially expand the range of applications to the surface analysis of bulk materials or liquid-solid interfaces.
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Affiliation(s)
- Yaroslav Odarchenko
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Anna Kaźmierczak-Bałata
- Institute of Physics, Center for Science and Education, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice, Poland
| | - Jerzy Bodzenta
- Institute of Physics, Center for Science and Education, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice, Poland
| | - Enrico Ferrari
- Department of Life Sciences, University of Lincoln, Lincoln LN6 7TS, UK
| | - Mikhail Soloviev
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
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7
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Wu L, Chen F, Chang X, Li L, Yin X, Li C, Wang F, Li C, Xu Q, Zhuang H, Gu N, Hua ZC. Combined Cellular Thermometry Reveals That Salmonella typhimurium Warms Macrophages by Inducing a Pyroptosis-like Phenotype. J Am Chem Soc 2022; 144:19396-19409. [PMID: 36228296 DOI: 10.1021/jacs.2c07287] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The attenuated Salmonella typhimurium VNP20009, enriched in tumors, is known to have antitumor effects and recruit macrophages. Little is known, however, about whether VNP will lead to specific changes in macrophages, e.g., cell temperature. Here, using a real-time wireless multicell thermometry system, we reported for the first time that VNP20009 increases the macrophage temperature by 0.2 °C. Nigericin, recognized as an inducer of pyroptosis, was found to induce macrophage warming. Moreover, the ΔsipD-VNP20009 strain failed to induce macrophage pyroptosis and simultaneously failed to warm macrophages, and the Gsdmd-/- macrophages that were unable to achieve pyroptosis were no longer warmed following VNP20009 induction. These results suggested that the occurrence of macrophage pyroptosis is the key to VNP20009-mediated cell warming. With the aid of a single-cell thermometry system, it was further confirmed that cell warming occurred in pyroptosis-like macrophages. Cellular warming was not detected after the induction of pyroptosis in macrophages with loss of mitochondrial biological function, suggesting a critical role of mitochondria in warming. Moreover, we found that VNP20009 caused local tumor temperature increases. The local tumor warming induced by VNP20009 was significantly reduced after macrophage clearance. Notably, this temperature increase contributed to M1-type polarization. These findings expanded our knowledge of the cellular biological changes induced by the strain on macrophages, as well as the biochemical phenomena accompanying pyroptosis, and provide a reference for the study of biochemical signals transduced to biothermal signals with a combined cell-level temperature detector.
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Affiliation(s)
- Leyang Wu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China.,Changzhou High-Tech Research Institute of Nanjing University and Jiangsu TargetPharma Laboratories Inc., Changzhou213164, China
| | - Feng Chen
- School of Biomedical Engineering and Informatics, Nanjing Medical University, Nanjing211166, China
| | - Xiaoyao Chang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China
| | - Lin Li
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China
| | - Xingpeng Yin
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China
| | - Can Li
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Sciences and Medical Engineering, Southeast University, Nanjing210096, China.,School of Artificial Intelligence and Information Technology, Nanjing University of Chinese Medicine, Nanjing210023, China
| | - Fangxu Wang
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Sciences and Medical Engineering, Southeast University, Nanjing210096, China
| | - Chenyang Li
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China
| | - Qin Xu
- Jiangsu Key Laboratory of Artificial Functional Materials, State Key Laboratory of Analytical Chemistry for Life Science, College of Engineering and Applied Sciences, Nanjing University, Nanjing210023, China
| | - Hongqin Zhuang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China
| | - Ning Gu
- School of Biomedical Engineering and Informatics, Nanjing Medical University, Nanjing211166, China.,State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Sciences and Medical Engineering, Southeast University, Nanjing210096, China
| | - Zi-Chun Hua
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing210023, China.,Changzhou High-Tech Research Institute of Nanjing University and Jiangsu TargetPharma Laboratories Inc., Changzhou213164, China.,School of Biopharmacy, China Pharmaceutical University, Nanjing211198, China
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8
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Wang Y, Zhu H, Feng J, Neuzil P. Recent advances of microcalorimetry for studying cellular metabolic heat. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Fujiwara M, Shikano Y. Diamond quantum thermometry: from foundations to applications. NANOTECHNOLOGY 2021; 32:482002. [PMID: 34416739 DOI: 10.1088/1361-6528/ac1fb1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Diamond quantum thermometry exploits the optical and electrical spin properties of colour defect centres in diamonds and, acts as a quantum sensing method exhibiting ultrahigh precision and robustness. Compared to the existing luminescent nanothermometry techniques, a diamond quantum thermometer can be operated over a wide temperature range and a sensor spatial scale ranging from nanometres to micrometres. Further, diamond quantum thermometry is employed in several applications, including electronics and biology, to explore these fields with nanoscale temperature measurements. This review covers the operational principles of diamond quantum thermometry for spin-based and all-optical methods, material development of diamonds with a focus on thermometry, and examples of applications in electrical and biological systems with demand-based technological requirements.
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Affiliation(s)
- Masazumi Fujiwara
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Yutaka Shikano
- Graduate School of Science and Technology, Gunma University, 4-2 Aramaki, Maebashi, Gunma 371-8510, Japan
- Quantum Computing Center, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama 223-8522, Japan
- Institute for Quantum Studies, Chapman University, 1 University Dr, Orange, CA 92866, United States of America
- JST PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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10
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Bae J, Zheng J, Zhang H, Foster PJ, Needleman DJ, Vlassak JJ. A Micromachined Picocalorimeter Sensor for Liquid Samples with Application to Chemical Reactions and Biochemistry. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2003415. [PMID: 33717854 PMCID: PMC7927623 DOI: 10.1002/advs.202003415] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/04/2020] [Indexed: 05/28/2023]
Abstract
Calorimetry has long been used to probe the physical state of a system by measuring the heat exchanged with the environment as a result of chemical reactions or phase transitions. Application of calorimetry to microscale biological samples, however, is hampered by insufficient sensitivity and the difficulty of handling liquid samples at this scale. Here, a micromachined calorimeter sensor that is capable of resolving picowatt levels of power is described. The sensor consists of low-noise thermopiles on a thin silicon nitride membrane that allow direct differential temperature measurements between a sample and four coplanar references, which significantly reduces thermal drift. The partial pressure of water in the ambient around the sample is maintained at saturation level using a small hydrogel-lined enclosure. The materials used in the sensor and its geometry are optimized to minimize the noise equivalent power generated by the sensor in response to the temperature field that develops around a typical sample. The experimental response of the sensor is characterized as a function of thermopile dimensions and sample volume, and its capability is demonstrated by measuring the heat dissipated during an enzymatically catalyzed biochemical reaction in a microliter-sized liquid droplet. The sensor offers particular promise for quantitative measurements on biological systems.
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Affiliation(s)
- Jinhye Bae
- Department of NanoEngineeringUniversity of California San DiegoLa JollaCA92093USA
| | - Juanjuan Zheng
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMA02138USA
| | - Haitao Zhang
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMA02138USA
| | - Peter J. Foster
- Physics of Living SystemsDepartment of PhysicsMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Daniel J. Needleman
- Department of Molecular and Cellular BiologyHarvard UniversityCambridgeMA02138USA
- Center for Computational BiologyFlatiron InstituteNew YorkNY10010USA
| | - Joost J. Vlassak
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMA02138USA
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11
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Abstract
Temperature is an important factor in the process of life, as thermal energy transfer participates in all biological events in organisms. Due to technical limitations, there is still a lot more information to be explored regarding the correlation between life activities and temperature changes. In recent years, the emergence of a variety of new temperature measurement methods has facilitated further research in this field. Here, we introduce the latest advances in temperature sensors for biological detection and their related applications in metabolic research. Various technologies are discussed in terms of their advantages and shortcomings, and future prospects are presented.
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Affiliation(s)
- Fangxu Wang
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Yuexia Han
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Ning Gu
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
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12
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Liu Y, Lehnert T, Gijs MAM. Fast antimicrobial susceptibility testing on Escherichia coli by metabolic heat nanocalorimetry. LAB ON A CHIP 2020; 20:3144-3157. [PMID: 32677656 DOI: 10.1039/d0lc00579g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fast spreading of antimicrobial resistance is now considered a major global health threat. New technologies are required, enabling rapid diagnostics of bacterial infection combined with fast antimicrobial susceptibility testing (AST) for evaluating the efficiency and dosage of antimicrobial compounds in vitro. This work presents an integrated chip-based isothermal nanocalorimetry platform for direct microbial metabolic heat measurements and evaluates its potential for fast AST. Direct detection of the bacteria-generated heat allows monitoring of metabolic activity and antimicrobial action at subinhibitory concentrations in real-time. The high heat sensitivity of the platform enables bacterial growth detection within only a few hours of incubation, whereas growth inhibition upon administration of antibiotics is revealed by a decrease or the absence of the heat signal. Antimicrobial stress results in lag phase extension and metabolic energy spilling. Oxygen consumption and optical density measurements provide a more holistic insight of the metabolic state and the evolution of bacterial biomass. As a proof-of-concept, a metabolic heat-based AST study on Escherichia coli as model organism with 3 clinically relevant antibiotics is performed and the minimum inhibitory concentrations are determined.
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Affiliation(s)
- Yang Liu
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - Thomas Lehnert
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - Martin A M Gijs
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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13
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Hong S, Dechaumphai E, Green CR, Lal R, Murphy AN, Metallo CM, Chen R. Sub-nanowatt microfluidic single-cell calorimetry. Nat Commun 2020; 11:2982. [PMID: 32532969 PMCID: PMC7292832 DOI: 10.1038/s41467-020-16697-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 05/18/2020] [Indexed: 12/02/2022] Open
Abstract
Non-invasive and label-free calorimetry could become a disruptive technique to study single cell metabolic heat production without altering the cell behavior, but it is currently limited by insufficient sensitivity. Here, we demonstrate microfluidic single-cell calorimetry with 0.2-nW sensitivity, representing more than ten-fold enhancement over previous record, which is enabled by (i) a low-noise thermometry platform with ultralow long-term (10-h) temperature noise (80 μK) and (ii) a microfluidic channel-in-vacuum design allowing cell flow and nutrient delivery while maintaining a low thermal conductance of 2.5 μW K−1. Using Tetrahymena thermophila as an example, we demonstrate on-chip single-cell calorimetry measurement with metabolic heat rates ranging from 1 to 4 nW, which are found to correlate well with the cell size. Finally, we perform real-time monitoring of metabolic rate stimulation by introducing a mitochondrial uncoupling agent to the microchannel, enabling determination of the spare respiratory capacity of the cells. Calorimetrically measuring the heat of single cells is currently not possible due to the sensitivity of existing calorimeters. Here the authors present on-chip single cell calorimetry, with a sensitivity over ten-fold greater than the current gold-standard.
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Affiliation(s)
- Sahngki Hong
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, 92093, USA.,Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Edward Dechaumphai
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Courtney R Green
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Ratneshwar Lal
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, 92093, USA.,Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093, USA.,Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Anne N Murphy
- Department of Pharmacology, University of California San Diego, La Jolla, CA, 92093, USA
| | - Christian M Metallo
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Renkun Chen
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, 92093, USA. .,Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093, USA.
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14
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Sub-nanowatt resolution direct calorimetry for probing real-time metabolic activity of individual C. elegans worms. Nat Commun 2020; 11:2983. [PMID: 32532993 PMCID: PMC7293274 DOI: 10.1038/s41467-020-16690-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 05/13/2020] [Indexed: 11/25/2022] Open
Abstract
Calorimetry has been widely used in metabolic studies, but direct measurements from individual small biological model organisms such as C. elegans or isolated single cells have been limited by poor sensitivity of existing techniques and difficulties in resolving very small heat outputs. Here, by careful thermal engineering, we developed a robust, highly sensitive and bio-compatible calorimetric platform that features a resolution of ~270 pW—more than a 500-fold improvement over the most sensitive calorimeter previously used for measuring the metabolic heat output of C. elegans. Using this calorimeter, we demonstrate time-resolved metabolic measurements of single C. elegans worms from larval to adult stages. Further, we show that the metabolic output is significantly lower in long-lived C. elegans daf-2 mutants. These demonstrations clearly highlight the broad potential of this tool for studying the role of metabolism in disease, development and aging of small model organisms and single cells. Calorimetry is widely used for metabolic studies, but measurements of single cells and small organisms are limited by the sensitivity of current techniques. Here the authors develop a sensitive platform for performing time-resolved metabolic measurements of single C. elegans worms from larval to adult stages.
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15
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You JB, Lee B, Choi Y, Lee CS, Peter M, Im SG, Lee SS. Nanoadhesive layer to prevent protein absorption in a poly(dimethylsiloxane) microfluidic device. Biotechniques 2020; 69:404-409. [PMID: 32372656 DOI: 10.2144/btn-2020-0025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Poly(dimethylsiloxane) (PDMS) is widely used as a microfluidics platform material; however, it absorbs various molecules, perturbing specific chemical concentrations in microfluidic channels. We present a simple solution to prevent adsorption into a PDMS microfluidic device. We used a vapor-phase-deposited nanoadhesive layer to seal PDMS microfluidic channels. Absorption of fluorescent molecules into PDMS was efficiently prevented in the nanolayer-treated PDMS device. Importantly, when cultured in a nanolayer-treated PDMS device, yeast cells exhibited the expected concentration-dependent response to a mating pheromone, including mating-specific morphological and gene expression changes, while yeast cultured in an untreated PDMS device did not properly respond to the pheromone. Our method greatly expands microfluidic applications that require precise control of molecule concentrations.
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Affiliation(s)
- Jae Bem You
- Department of Chemical & Materials Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Byungjin Lee
- Department of Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Yunho Choi
- Department of Chemical & Biomolecular Engineering, KAIST, Daejeon, 34141, Republic of Korea
| | - Chang-Soo Lee
- Department of Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Matthias Peter
- Institute for Biochemistry, ETH Zürich, Zürich, CH 8093, Switzerland
| | - Sung Gap Im
- Department of Chemical & Biomolecular Engineering, KAIST, Daejeon, 34141, Republic of Korea
| | - Sung Sik Lee
- Institute for Biochemistry, ETH Zürich, Zürich, CH 8093, Switzerland.,Scientific Center for Optical & Electron Microscopy (ScopeM), ETH Zürich, Zürich, CH 8093, Switzerland
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16
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Short-term temperature change detections and frequency signals in single cultured cells using a microfabricated thermistor. SENSING AND BIO-SENSING RESEARCH 2020. [DOI: 10.1016/j.sbsr.2019.100309] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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17
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Wang S, Sha X, Yu S, Zhao Y. Nanocalorimeters for biomolecular analysis and cell metabolism monitoring. BIOMICROFLUIDICS 2020; 14:011503. [PMID: 32038739 PMCID: PMC6994269 DOI: 10.1063/1.5134870] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/10/2020] [Indexed: 05/28/2023]
Abstract
Nanocalorimeters, or microfabricated calorimeters, provide a promising way to characterize the thermal process of biological processes, such as biomolecule interactions and cellular metabolic activities. They enabled miniaturized heat measurement onto a chip device with potential benefits including low sample consumption, low cost, portability, and high throughput. Over the past few decades, researchers have tried to improve nanocalorimeters' performance, in terms of sensitivity, accuracy, and detection resolution, by exploring different sensing methods, thermal insulation techniques, and liquid handling methods. The enhanced devices resulted in new applications in recent years, and here we have summarized the performance parameters and applications based on categories. Finally, we have listed the current technical difficulties in nanocalorimeter research and hope for future solutions to overcome them.
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Affiliation(s)
- Shuyu Wang
- Department of Control Engineering, Northeastern University, Qinhuangdao, Hebei 066001, People’s Republic of China
| | - Xiaopeng Sha
- Department of Control Engineering, Northeastern University, Qinhuangdao, Hebei 066001, People’s Republic of China
| | - Shifeng Yu
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, USA
| | - Yuliang Zhao
- Department of Control Engineering, Northeastern University, Qinhuangdao, Hebei 066001, People’s Republic of China
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18
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Abstract
Isothermal titration calorimetry (ITC) can benefit from operating in miniaturized devices as they enable quantitative, low-cost measurements with reduced analysis time and reagents consumption. However, most of the existing devices that offer ITC capabilities either do not yet allow proper control of reaction conditions or are limited by issues such as evaporation or surface adsorption caused inaccurate solution concentration information and unintended changes in biomolecular properties because of aggregation. In this paper, we present a microdevice that combines 3D-printed microfluidic structures with a polymer-based MEMS thermoelectric sensor to enable quantitative ITC measurements of biomolecular interactions. Benefitting from the geometric flexibility of 3D-printing, the microfluidic design features calorimetric chambers in a differential cantilever configuration that improves the thermal insulation and reduces the thermal mass of the implementing device. Also, 3D-printing microfluidic structures use non-permeable materials to avoid potential adsorption. Finally, the robustness of the polymeric MEMS sensor chip allows the device to be assembled reversibly and leak-free, and hence reusable. We demonstrate the utility of the device by quantitative ITC characterization of a biomolecular binding system, ribonuclease A (RNase A) bind with cytidine 2'-monophosphate (2'CMP) down to a practically useful sample concentration of 0.2 mM. The thermodynamic parameters of the binding system, including the stoichiometry, equilibrium binding constant, and enthalpy change are obtained and found to agree with values previously reported in the literature.
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19
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Lubbers B, Kazura E, Dawson E, Mernaugh R, Baudenbacher F. Microfabricated calorimeters for thermometric enzyme linked immunosorbent assay in one-Nanoliter droplets. Biomed Microdevices 2019; 21:85. [PMID: 31451947 DOI: 10.1007/s10544-019-0429-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Advances in microfabrication allow for highly sensitive calorimeters with dramatically reduced volume, decreased response time and increased energy resolution. These calorimeters hold the potential for designs of ELISA platforms competitive with fluorescent and chemiluminescent technologies. We have developed a new assay platform using conventional ELISA reagents to produce a thermal signal quantifiable using calorimetry. Our optimized micromachined calorimeters have nL reaction volumes and a minimum detectable power of 375 pW/Hz1/2. We demonstrate rapid quantification in a model system of trastuzumab, a humanized monoclonal antibody used in the treatment of HER2 overexpressing breast cancers, in human serum using a HER2 peptide mimetic. Trastuzumab concentration and reaction time constant correlated well (R2 = 0.954) and can be used to determine trastuzumab concentrations. The limit of detection for the ThermometricELISA (TELISA) was 10 μg/ml trastuzumab in human serum. TELISA allows for a simple readout, reduction in assay time, sample and reagent volumes and has the potential to become a point of care multiplexed platform technology.
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Affiliation(s)
- Brad Lubbers
- Department of Biomedical Engineering, Vanderbilt University, PMB 351631, 2301 Vanderbilt Place, Nashville, TN, 37235-1631, USA
| | - Evan Kazura
- Department of Biomedical Engineering, Vanderbilt University, PMB 351631, 2301 Vanderbilt Place, Nashville, TN, 37235-1631, USA
| | - Elliott Dawson
- BioVentures, Inc., 1435 Kensington Square Court, P.O. Box 2561, Murfreesboro, TN, 37133-2561, USA
| | - Ray Mernaugh
- Vanderbilt University School of Medicine, PRB 895, Nashville, TN, 37232, USA
| | - Franz Baudenbacher
- Department of Biomedical Engineering, Vanderbilt University, PMB 351631, 2301 Vanderbilt Place, Nashville, TN, 37235-1631, USA.
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20
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Behera B, Anil Vishnu GK, Chatterjee S, Sitaramgupta V VSN, Sreekumar N, Nagabhushan A, Rajendran N, Prathik BH, Pandya HJ. Emerging technologies for antibiotic susceptibility testing. Biosens Bioelectron 2019; 142:111552. [PMID: 31421358 DOI: 10.1016/j.bios.2019.111552] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/27/2019] [Accepted: 07/29/2019] [Indexed: 12/22/2022]
Abstract
Superbugs such as infectious bacteria pose a great threat to humanity due to an increase in bacterial mortality leading to clinical treatment failure, lengthy hospital stay, intravenous therapy and accretion of bacteraemia. These disease-causing bacteria gain resistance to drugs over time which further complicates the treatment. Monitoring of antibiotic resistance is therefore necessary so that bacterial infectious diseases can be diagnosed rapidly. Antimicrobial susceptibility testing (AST) provides valuable information on the efficacy of antibiotic agents and their dosages for treatment against bacterial infections. In clinical laboratories, most widely used AST methods are disk diffusion, gradient diffusion, broth dilution, or commercially available semi-automated systems. Though these methods are cost-effective and accurate, they are time-consuming, labour-intensive, and require skilled manpower. Recently much attention has been on developing rapid AST techniques to avoid misuse of antibiotics and provide effective treatment. In this review, we have discussed emerging engineering AST techniques with special emphasis on phenotypic AST. These techniques include fluorescence imaging along with computational image processing, surface plasmon resonance, Raman spectra, and laser tweezer as well as micro/nanotechnology-based device such as microfluidics, microdroplets, and microchamber. The mechanical and electrical behaviour of single bacterial cell and bacterial suspension for the study of AST is also discussed.
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Affiliation(s)
- Bhagaban Behera
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - G K Anil Vishnu
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India; Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India
| | - Suman Chatterjee
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - V S N Sitaramgupta V
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Niranjana Sreekumar
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Apoorva Nagabhushan
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | | | - B H Prathik
- Indira Gandhi Institute of Child Health, Bangalore, India
| | - Hardik J Pandya
- Biomedical and Electronic (10(-6)-10(-9)) Engineering Systems Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India.
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21
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Feng J, Svatoš V, Liu X, Chang H, Neužil P. High-performance microcalorimeters: Design, applications and future development. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.09.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Ronzetti M, Baljinnyam B, Yasgar A, Simeonov A. Testing for drug-human serum albumin binding using fluorescent probes and other methods. Expert Opin Drug Discov 2018; 13:1005-1014. [DOI: 10.1080/17460441.2018.1534824] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Michael Ronzetti
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Bolormaa Baljinnyam
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Adam Yasgar
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
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23
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Fiorino A, Thompson D, Yadlapalli S, Jiang C, Shafer OT, Reddy P, Meyhofer E. Parallelized, real-time, metabolic-rate measurements from individual Drosophila. Sci Rep 2018; 8:14452. [PMID: 30262912 PMCID: PMC6160429 DOI: 10.1038/s41598-018-32744-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 09/13/2018] [Indexed: 12/24/2022] Open
Abstract
Significant recent evidence suggests that metabolism is intricately linked to the regulation and dysfunction of complex cellular and physiological responses ranging from altered metabolic programs in cancers and aging to circadian rhythms and molecular clocks. While the metabolic pathways and their fundamental control mechanisms are well established, the precise cellular mechanisms underpinning, for example, enzymatic pathway control, substrate preferences or metabolic rates, remain far less certain. Comprehensive, continuous metabolic studies on model organisms, such as the fruit fly Drosophila melanogaster, may provide a critical tool for deciphering these complex physiological responses. Here, we describe the development of a high-resolution calorimeter, which combines sensitive thermometry with optical imaging to concurrently perform measurements of the metabolic rate of ten individual flies, in real-time, with ~100 nW resolution. Using this calorimeter we have measured the mass-specific metabolic rates of flies of different genotypes, ages, and flies fed with different diets. This powerful new approach enables systematic studies of the metabolic regulation related to cellular and physiological function and disease mechanisms.
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Affiliation(s)
- Anthony Fiorino
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Dakotah Thompson
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Swathi Yadlapalli
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Chang Jiang
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Orie T Shafer
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Pramod Reddy
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Edgar Meyhofer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA. .,Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
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24
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Yang F, Yang N, Huo X, Xu S. Thermal sensing in fluid at the micro-nano-scales. BIOMICROFLUIDICS 2018; 12:041501. [PMID: 30867860 PMCID: PMC6404956 DOI: 10.1063/1.5037421] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/19/2018] [Indexed: 06/09/2023]
Abstract
Temperature is one of the most fundamental parameters for the characterization of a physical system. With rapid development of lab-on-a-chip and biology at single cell level, a great demand has risen for the temperature sensors with high spatial, temporal, and thermal resolution. Nevertheless, measuring temperature in liquid environment is always a technical challenge. Various factors may affect the sensing results, such as the fabrication parameters of built-in sensors, thermal property of electrical insulating layer, and stability of fluorescent thermometers in liquid environment. In this review, we focused on different kinds of micro/nano-thermometers applied in the thermal sensing for microfluidic systems and cultured cells. We discussed the advantages and limitations of these thermometers in specific applications and the challenges and possible solutions for more accurate temperature measurements in further studies.
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Affiliation(s)
- Fan Yang
- Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, People's Republic of China
| | - Nana Yang
- Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, People's Republic of China
| | - Xiaoye Huo
- Faculty of Mechanical Engineering, Micro-and Nanofluidics Laboratory, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Shengyong Xu
- Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, People's Republic of China
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25
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26
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Krenger R, Lehnert T, Gijs MAM. Dynamic microfluidic nanocalorimetry system for measuring Caenorhabditis elegans metabolic heat. LAB ON A CHIP 2018; 18:1641-1651. [PMID: 29770425 DOI: 10.1039/c8lc00238j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Basal heat production is a key phenotype for assessing the metabolic activity of small living organisms. Here, we present a new nanocalorimetric system, based on thin film thermopile sensors combined with microfluidic chips for measuring metabolic heat signals generated by Caenorhabditis elegans larval populations (60 to 220 organisms). In addition to versatile on-chip fluidic manipulation, our microfluidic approach allows confining worm populations close to the sensor surface, thus increasing the sensitivity of the assays. A customized flow protocol for dynamically displacing the worm population on-chip and off-chip was applied. The resulting sequential recordings of heat source and reference signals enabled precise measurements of slow varying heat-generating metabolic processes. We found an increase of the volume-specific basal heat production from the L2 to the L3 larval stage, and a significant decrease from the L3 to the L4 stage. Additionally, we investigated the metabolic heat production of the larval populations during maximal respiratory capacity, i.e. after inducing uncoupled respiration by on-chip treatment with the mitochondrial uncoupling agent carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP). Depending on the larval stage, inducing uncoupled respiration causes an increase of the metabolic heat production ranging from 55% up to 95% with respect to untreated worms.
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Affiliation(s)
- Roger Krenger
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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27
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Chamoun J, Pattekar A, Afshinmanesh F, Martini J, Recht MI. Optical calorimetry in microfluidic droplets. LAB ON A CHIP 2018; 18:1581-1592. [PMID: 29745386 PMCID: PMC5999407 DOI: 10.1039/c7lc01266g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A novel microfluidic calorimeter that measures the enthalpy change of reactions occurring in 100 μm diameter aqueous droplets in fluoropolymer oil has been developed. The aqueous reactants flow into a microfluidic droplet generation chip in separate fluidic channels, limiting contact between the streams until immediately before they form the droplet. The diffusion-driven mixing of reactants is predominantly restricted to within the droplet. The temperature change in droplets due to the heat of reaction is measured optically by recording the reflectance spectra of encapsulated thermochromic liquid crystals (TLC) that are added to one of the reactant streams. As the droplets travel through the channel, the spectral characteristics of the TLC represent the internal temperature, allowing optical measurement with a precision of ≈6 mK. The microfluidic chip and all fluids are temperature controlled, and the reaction heat within droplets raises their temperature until thermal diffusion dissipates the heat into the surrounding oil and chip walls. Position resolved optical temperature measurement of the droplets allows calculation of the heat of reaction by analyzing the droplet temperature profile over time. Channel dimensions, droplet generation rate, droplet size, reactant stream flows and oil flow rate are carefully balanced to provide rapid diffusional mixing of reactants compared to thermal diffusion, while avoiding thermal "quenching" due to contact between the droplets and the chip walls. Compared to conventional microcalorimetry, which has been used in this work to provide reference measurements, this new continuous flow droplet calorimeter has the potential to perform titrations ≈1000-fold faster while using ≈400-fold less reactants per titration.
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Affiliation(s)
- Jacob Chamoun
- Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, CA 94304, USA.
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28
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Shrirao AB, Fritz Z, Novik EM, Yarmush GM, Schloss RS, Zahn JD, Yarmush ML. Microfluidic flow cytometry: The role of microfabrication methodologies, performance and functional specification. TECHNOLOGY 2018; 6:1-23. [PMID: 29682599 PMCID: PMC5907470 DOI: 10.1142/s2339547818300019] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Flow cytometry is an invaluable tool utilized in modern biomedical research and clinical applications requiring high throughput, high resolution particle analysis for cytometric characterization and/or sorting of cells and particles as well as for analyzing results from immunocytometric assays. In recent years, research has focused on developing microfluidic flow cytometers with the motivation of creating smaller, less expensive, simpler, and more autonomous alternatives to conventional flow cytometers. These devices could ideally be highly portable, easy to operate without extensive user training, and utilized for research purposes and/or point-of-care diagnostics especially in limited resource facilities or locations requiring on-site analyses. However, designing a device that fulfills the criteria of high throughput analysis, automation and portability, while not sacrificing performance is not a trivial matter. This review intends to present the current state of the field and provide considerations for further improvement by focusing on the key design components of microfluidic flow cytometers. The recent innovations in particle focusing and detection strategies are detailed and compared. This review outlines performance matrix parameters of flow cytometers that are interdependent with each other, suggesting trade offs in selection based on the requirements of the applications. The ongoing contribution of microfluidics demonstrates that it is a viable technology to advance the current state of flow cytometry and develop automated, easy to operate and cost-effective flow cytometers.
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Affiliation(s)
- Anil B Shrirao
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Zachary Fritz
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Eric M Novik
- Hurel Corporation, 671, Suite B, U.S. Highway 1, North Brunswick, NJ 08902
| | - Gabriel M Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Rene S Schloss
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Jeffrey D Zahn
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Martin L Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
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29
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Gaddes D, Reeves WB, Tadigadapa S. Calorimetric Biosensing System for Quantification of Urinary Creatinine. ACS Sens 2017; 2:796-802. [PMID: 28723128 DOI: 10.1021/acssensors.7b00161] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In this work, we demonstrate the quantification of creatinine in human urine samples using a microcalorimetric sensing system. The calorimetric sensor is based on an array of microfabricated Y-cut quartz resonators. The piezoelectric quartz is etched down to a thickness of 10 μm and exhibits a bulk acoustic resonance of 166 MHz. The temperature sensitivity of this high-frequency quartz resonator is 14 600 Hz/K due to the high phenomenological sensitivity of quartz. Most importantly, the quartz sensors and the analyte fluidics are decoupled providing a significantly more robust calorimetric sensing system than directly contacted chip calorimeters. A reference resonator, consisting of a suspended structure held by four arms, was realized to thermal isolation from the bulk quartz by using focused ion beam etching. We employ alginate entrapped creatinine deiminase to transduce urinary creatinine into temperature signatures, permitting the quantification of creatinine. Fairly good agreement with the measured creatinine values in the 5 urine samples using calorimetric and HPLC methods is obtained.
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Affiliation(s)
| | - William Brian Reeves
- Department
of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
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30
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Glotz G, Knoechel DJ, Podmore P, Gruber-Woelfler H, Kappe CO. Reaction Calorimetry in Microreactor Environments—Measuring Heat of Reaction by Isothermal Heat Flux Calorimetry. Org Process Res Dev 2017. [DOI: 10.1021/acs.oprd.7b00092] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriel Glotz
- Institute
of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria
- Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
| | - Donald J. Knoechel
- Fauske and Associates LLC, 16W070 83rd Street, Burr Ridge, Illinois 60527, United States
| | - Philip Podmore
- Syrris Ltd., 27 Jarman Way, Royston, Hertfordshire, United Kingdom
| | - Heidrun Gruber-Woelfler
- Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
- Institute
of Process and Particle Engineering, Graz University of Technology, Inffeldgasse 13/III, 8010 Graz, Austria
| | - C. Oliver Kappe
- Institute
of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria
- Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
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31
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Kim J, You JB, Nam SM, Seo S, Im SG, Lee W. Rollable Microfluidic Systems with Microscale Bending Radius and Tuning of Device Function with Reconfigurable 3D Channel Geometry. ACS APPLIED MATERIALS & INTERFACES 2017; 9:11156-11166. [PMID: 28267308 DOI: 10.1021/acsami.7b00741] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Flexible microfluidic system is an essential component of wearable biosensors to handle body fluids. A parylene-based, thin-film microfluidic system is developed to achieve flexible microfluidics with microscale bending radius. A new molding and bonding technique is developed for parylene microchannel fabrication. Bonding with nanoadhesive layers deposited by initiated chemical vapor deposition (iCVD) enables the construction of microfluidic channels with short fabrication time and high bonding strength. The high mechanical strength of parylene allows less channel deformation from the internal pressure for the thin-film parylene channel than bulk PDMS channel. At the same time, negligible channel sagging or collapse is observed during channel bending down to a few hundreds of micrometers due to stress relaxation by prestretch structure. The flexible parylene channels are also developed into a rollable microfluidic system. In a rollable microfluidics format, 2D parylene channels can be rolled around a capillary tubing working as inlets to minimize the device footprint. In addition, we show that creating reconfigurable 3D channel geometry with microscale bending radius can lead to tunable device function: tunable Dean-flow mixer is demonstrated using reconfigurable microscale 3D curved channel. Flexible parylene microfluidics with microscale bending radius is expected to provide an important breakthrough for many fields including wearable biosensors and tunable 3D microfluidics.
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Affiliation(s)
- Jihye Kim
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
| | - Jae Bem You
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
| | - Sung Min Nam
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
| | - Sumin Seo
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
| | - Sung Gap Im
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
- KAIST Institute for NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
| | - Wonhee Lee
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
- KAIST Institute for NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141, Republic of Korea
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Natesan H, Bischof JC. Multiscale Thermal Property Measurements for Biomedical Applications. ACS Biomater Sci Eng 2017; 3:2669-2691. [PMID: 33418696 DOI: 10.1021/acsbiomaterials.6b00565] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Bioheat transfer-based innovations in health care include applications such as focal treatments for cancer and cardiovascular disease and the preservation of tissues and organs for transplantation. In these applications, the ability to preserve or destroy a biomaterial is directly dependent on its temperature history. Thus, thermal measurement and modeling are necessary to either avoid or induce the injury required. In this review paper, we will first define and discuss thermal conductivity and calorimetric measurements of biomaterials in the cryogenic (<-40 °C), subzero (<0 °C), hypothermic (<37 °C), and hyperthermic (>37 °C) regimes. For thermal conductivity measurements, we review the use of 3ω and laser flash techniques for measurement of thermal conductivity in thin (1 μm-2 mm thick), anisotropic, and/or multilayered tissues. At the nanoscale, we review the use of pump-probe and scanning probe methods to measure thermal conductivity at short temporal scales (10 ps-100 ns) and spatial scales (1 nm-1 μm), particularly in the coating and surrounding medium around metallic nanoparticles (1 nm-20 nm). For calorimetric techniques, we review differential scanning calorimetry (DSC), which is intrinsically at the microscale (e.g., tissue pieces or millions of cells in media). DSC is used with large sample mass (∼3-100 mg) over wide temperature ranges (-180 to 750 °C) with low-temperature scanning rates (<750 °C/min). The need to assess smaller samples at higher rates has led to the development of nanocalorimetry on a silicon based membrane. Here the sample weight is as low as 10 ng, thereby allowing ultra-rapid heating rates (∼1 × 107 C/min). Finally, we discuss various opportunities that are driving the need for new micro- and nanoscale thermal measurements.
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Affiliation(s)
- Harishankar Natesan
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - John C Bischof
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Wang S, Yu S, Siedler MS, Ihnat PM, Filoti DI, Lu M, Zuo L. Micro-differential scanning calorimeter for liquid biological samples. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:105005. [PMID: 27802741 DOI: 10.1063/1.4965443] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We developed an ultrasensitive micro-DSC (differential scanning calorimeter) for liquid protein sample characterization. This design integrated vanadium oxide thermistors and flexible polymer substrates with microfluidics chambers to achieve a high sensitivity (6 V/W), low thermal conductivity (0.7 mW/K), high power resolutions (40 nW), and well-defined liquid volume (1 μl) calorimeter sensor in a compact and cost-effective way. We further demonstrated the performance of the sensor with lysozyme unfolding. The measured transition temperature and enthalpy change were in accordance with the previous literature data. This micro-DSC could potentially raise the prospect of high-throughput biochemical measurement by parallel operation with miniaturized sample consumption.
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Affiliation(s)
- Shuyu Wang
- Department of Mechanical Engineering, Stony Brook University, Stony Brook, New York 11794, USA
| | - Shifeng Yu
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA
| | | | - Peter M Ihnat
- AbbVie Bioresearch Center, Worcester, Massachusetts 01605, USA
| | - Dana I Filoti
- AbbVie Bioresearch Center, Worcester, Massachusetts 01605, USA
| | - Ming Lu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Lei Zuo
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA
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Inomata N, Toda M, Ono T. Highly sensitive thermometer using a vacuum-packed Si resonator in a microfluidic chip for the thermal measurement of single cells. LAB ON A CHIP 2016; 16:3597-603. [PMID: 27526966 DOI: 10.1039/c6lc00949b] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A highly sensitive thermometer system for a living cell is proposed, fabricated, and evaluated. The system possesses a resonant thermal sensor surrounded by vacuum in a microfluidic chip. The measurement principle relies on resonant frequency tracking of the resonator in temperature variations due to the heat from a sample cell; the heat is conducted from the sample cell in the microfluidic channel via a heat guide connecting the resonator to a sample stage. This configuration can reduce heat loss from the resonator to the surroundings and damping in water. Two types of resonators are prepared, i.e., a cantilevered resonator and a double-supported resonator. The resonator sizes as a sensor are 30 × 50 × 1.5 μm in the cantilevered resonator, 30 × 75 × 0.40 μm in the double-supported one, respectively. The temperature and thermal resolutions of 79 μK and 1.90 nW, respectively, are achieved using the double-supported resonator. Two types of heat emissions from single brown fat cells are detected; one is continuous heat generation in the presence of chemical stimulation by a norepinephrine solution, and the other is pulsed without any stimulation.
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Affiliation(s)
- Naoki Inomata
- Department of Mechanical Systems and Design, Tohoku University, 6-6-01, aza-Aoba, Aramaki, Aoba, Sendai, Japan.
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35
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Gaddes DE, Demirel MC, Reeves WB, Tadigadapa S. Remote calorimetric detection of urea via flow injection analysis. Analyst 2016; 140:8033-40. [PMID: 26479269 DOI: 10.1039/c5an01306b] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The design and development of a calorimetric biosensing system enabling relatively high throughput sample analysis are reported. The calorimetric biosensor system consists of a thin (∼20 μm) micromachined Y-cut quartz crystal resonator (QCR) as a temperature sensor placed in close proximity to a fluidic chamber packed with an immobilized enzyme. Layer by layer enzyme immobilization of urease is demonstrated and its activity as a function of the number of layers, pH, and time has been evaluated. This configuration enables a sensing system where a transducer element is physically separated from the analyte solution of interest and is thereby free from fouling effects typically associated with biochemical reactions occuring on the sensor surface. The performance of this biosensing system is demonstrated by detection of 1-200 mM urea in phosphate buffer via a flow injection analysis (FIA) technique. Miniaturized fluidic systems were used to provide continuous flow through a reaction column. Under this configuration the biosensor has an ultimate resolution of less than 1 mM urea and showed a linear response between 0-50 mM. This work demonstrates a sensing modality in which the sensor itself is not fouled or contaminated by the solution of interest and the enzyme immobilized Kapton® fluidic reaction column can be used as a disposable cartridge. Such a system enables reuse and reliability for long term sampling measurements. Based on this concept a biosensing system is envisioned which can perform rapid measurements to detect biomarkers such as glucose, creatinine, cholesterol, urea and lactate in urine and blood continuously over extended periods of time.
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Affiliation(s)
- David E Gaddes
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Melik C Demirel
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA and Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA
| | - W Brian Reeves
- Department of Nephrology, Milton S. Hershey College of Medicine, The Pennsylvania State University, University Park, PA, USA
| | - Srinivas Tadigadapa
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA and Department of Electrical Engineering, The Pennsylvania State University, University Park, PA, USA.
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Wang B, Jia Y, Lin Q. A microfabrication-based approach to quantitative isothermal titration calorimetry. Biosens Bioelectron 2016; 78:438-446. [DOI: 10.1016/j.bios.2015.11.069] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 11/19/2015] [Accepted: 11/24/2015] [Indexed: 10/22/2022]
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Bhargava KC, Thompson B, Tembhekar A, Malmstadt N. Temperature Sensing in Modular Microfluidic Architectures. MICROMACHINES 2016; 7:mi7010011. [PMID: 30407384 PMCID: PMC6190081 DOI: 10.3390/mi7010011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 12/28/2015] [Accepted: 01/06/2016] [Indexed: 11/16/2022]
Abstract
A discrete microfluidic element with integrated thermal sensor was fabricated and demonstrated as an effective probe for process monitoring and prototyping. Elements were constructed using stereolithography and market-available glass-bodied thermistors within the modular, standardized framework of previous discrete microfluidic elements demonstrated in the literature. Flow rate-dependent response due to sensor self-heating and microchannel heating and cooling was characterized and shown to be linear in typical laboratory conditions. An acid-base neutralization reaction was performed in a continuous flow setting to demonstrate applicability in process management: the ratio of solution flow rates was varied to locate the equivalence point in a titration, closely matching expected results. This element potentially enables complex, three-dimensional microfluidic architectures with real-time temperature feedback and flow rate sensing, without application specificity or restriction to planar channel routing formats.
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Affiliation(s)
- Krisna C Bhargava
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.
| | - Bryant Thompson
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
| | - Anoop Tembhekar
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
| | - Noah Malmstadt
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.
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Mechref E, Jabbour J, Calas-Etienne S, Amro K, Mehdi A, Tauk R, Etienne P. New organic–inorganic hybrid material based on a poly(amic acid) oligomer: a promising opportunity to obtain microfluidic devices by a photolithographic process. RSC Adv 2016. [DOI: 10.1039/c6ra10584j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Miniaturized total analysis systems are becoming a powerful tool for analytical and bioanalytical applications.
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Affiliation(s)
- Elias Mechref
- Charles Coulomb Laboratory
- University of Montpellier
- UMR 5221
- 34095 Montpellier Cedex 5
- France
| | - Jihane Jabbour
- Platform for Research in Nanosciences and Nanotechnology
- Faculty of Sciences 2
- Lebanese University
- Lebanon
| | - Sylvie Calas-Etienne
- Charles Coulomb Laboratory
- University of Montpellier
- UMR 5221
- 34095 Montpellier Cedex 5
- France
| | - Kassem Amro
- Charles Coulomb Laboratory
- University of Montpellier
- UMR 5221
- 34095 Montpellier Cedex 5
- France
| | - Ahmad Mehdi
- Institute Charles Gerhardt
- Chimie Moléculaire et Organisation du Solide
- University of Montpellier
- UMR 5253
- 34095 Montpellier Cedex 5
| | - Rabih Tauk
- Platform for Research in Nanosciences and Nanotechnology
- Faculty of Sciences 2
- Lebanese University
- Lebanon
| | - Pascal Etienne
- Charles Coulomb Laboratory
- University of Montpellier
- UMR 5221
- 34095 Montpellier Cedex 5
- France
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Sen MA, Kowalski GJ, Fiering J, Larson D. A continuous flow microfluidic calorimeter: 3-D numerical modeling with aqueous reactants. THERMOCHIMICA ACTA 2015; 603:184-196. [PMID: 25937678 PMCID: PMC4415394 DOI: 10.1016/j.tca.2014.09.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A computational analysis of the reacting flow field, species diffusion and heat transfer processes with thermal boundary layer effects in a microchannel reactor with a coflow configuration was performed. Two parallel adjacent streams of aqueous reactants flow along a wide, shallow, enclosed channel in contact with a substrate, which is affixed to a temperature controlled plate. The Fluent computational fluid dynamics package solved the Navier-Stokes, mass transport and energy equations. The energy model, including the enthalpy of reaction as a nonuniform heat source, was validated by calculating the energy balance at several control volumes in the microchannel. Analysis reveals that the temperature is nearly uniform across the channel thickness, in the direction normal to the substrate surface; hence, measurements made by sensors at or near the surface are representative of the average temperature. Additionally, modeling the channel with a glass substrate and a silicone cover shows that heat transfer is predominantly due to the glass substrate. Finally, using the numerical results, we suggest that a microcalorimeter could be based on this configuration, and that temperature sensors such as optical nanohole array sensors could have sufficient spatial resolution to determine enthalpy of reaction.
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Affiliation(s)
- Mehmet A. Sen
- Northeastern University, Department of Mechanical and Industrial Engineering, 360 Hungtington Avenue, 334 Snell Engineering Center, Boston, MA 02115, USA
| | - Gregory J. Kowalski
- Northeastern University, Department of Mechanical and Industrial Engineering, 360 Hungtington Avenue, 334 Snell Engineering Center, Boston, MA 02115, USA
| | - Jason Fiering
- Charles Stark Draper Laboratory, 555 Technology Square, Cambridge, MA 02139, USA
| | - Dale Larson
- Charles Stark Draper Laboratory, 555 Technology Square, Cambridge, MA 02139, USA
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40
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Fabrication and characterization of a multichannel 3D thermopile for chip calorimeter applications. SENSORS 2015; 15:3351-61. [PMID: 25654716 PMCID: PMC4367362 DOI: 10.3390/s150203351] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 01/19/2015] [Accepted: 01/26/2015] [Indexed: 11/17/2022]
Abstract
Thermal sensors based on thermopiles are some of the most robust and popular temperature sensing technologies across industries and research disciplines. A chip calorimeter with a 3D thermopile layout with a large sensing area and multichannel capacity has been developed, which is highly desired for many applications requiring large reaction chambers or high throughputs, such as biofilm research, drug screening, etc. The performance of the device, including temperature sensitivity and heat power sensitivity, was evaluated. The capability to split the chip calorimeter to multiple channels was also demonstrated, which makes the chip calorimeter very flexible and powerful in many applications.
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41
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Roy-Panzer S, Kodama T, Lingamneni S, Panzer MA, Asheghi M, Goodson KE. Thermal characterization and analysis of microliter liquid volumes using the three-omega method. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:024901. [PMID: 25725871 DOI: 10.1063/1.4907353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Thermal phenomena in many biological systems offer an alternative detection opportunity for quantifying relevant sample properties. While there is substantial prior work on thermal characterization methods for fluids, the push in the biology and biomedical research communities towards analysis of reduced sample volumes drives a need to extend and scale these techniques to these volumes of interest, which can be below 100 pl. This work applies the 3ω technique to measure the temperature-dependent thermal conductivity and heat capacity of de-ionized water, silicone oil, and salt buffer solution droplets from 24 to 80 °C. Heater geometries range in length from 200 to 700 μm and in width from 2 to 5 μm to accommodate the size restrictions imposed by small volume droplets. We use these devices to measure droplet volumes of 2 μl and demonstrate the potential to extend this technique down to pl droplet volumes based on an analysis of the thermally probed volume. Sensitivity and uncertainty analyses provide guidance for relevant design variables for characterizing properties of interest by investigating the tradeoffs between measurement frequency regime, device geometry, and substrate material. Experimental results show that we can extract thermal conductivity and heat capacity with these sample volumes to within less than 1% of thermal properties reported in the literature.
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Affiliation(s)
- Shilpi Roy-Panzer
- Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
| | - Takashi Kodama
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - Srilakshmi Lingamneni
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - Matthew A Panzer
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - Mehdi Asheghi
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - Kenneth E Goodson
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
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Kopparthy VL, Tangutooru SM, Guilbeau EJ. Label Free Detection of L-Glutamate Using Microfluidic Based Thermal Biosensor. Bioengineering (Basel) 2015; 2:2-14. [PMID: 28955010 PMCID: PMC5597124 DOI: 10.3390/bioengineering2010002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/07/2015] [Indexed: 01/09/2023] Open
Abstract
A thermoelectric biosensor for the detection of L-glutamate concentration was developed. The thermoelectric sensor is integrated into a micro-calorimeter which measures the heat produced by biochemical reactions. The device contains a single flow channel that is 120 µm high and 10 mm wide with two fluid inlets and one fluid outlet. An antimony-bismuth (Sb-Bi) thermopile with high common mode rejection ratio is attached to the lower channel wall and measures the dynamic changes in the temperature when L-glutamate undergoes oxidative deamination in the presence of glutamate oxidase (GLOD). The thermopile has a Seebeck coefficient of ~7 µV·(m·K)−1. The device geometry, together with hydrodynamic focusing, eliminates the need of extensive temperature control. Layer-by-layer assembly is used to immobilize GLOD on the surface of glass coverslips by alternate electrostatic adsorption of polyelectrolyte and GLOD. The impulse injection mode using a 6-port injection valve minimizes sample volume to 5 µL. The sensitivity of the sensor for glutamate is 17.9 nVs·mM−1 in the linear range of 0–54 mM with an R2 value of 0.9873. The lowest detection limit of the sensor for glutamate is 5.3 mM.
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Affiliation(s)
- Varun Lingaiah Kopparthy
- The Center for Biomedical Engineering and Rehabilitation Science, Louisiana Tech University, Ruston, LA 71272, USA.
| | - Siva Mahesh Tangutooru
- Department of Mechanical & Industrial Engineering, Qatar University, P.O. Box 2713, Doha, Qatar.
| | - Eric J Guilbeau
- The Center for Biomedical Engineering and Rehabilitation Science, Louisiana Tech University, Ruston, LA 71272, USA.
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43
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Padovani R, Lehnert T, Trouillon R, Gijs MAM. Nanocalorimetric platform for accurate thermochemical studies in microliter volumes. RSC Adv 2015. [DOI: 10.1039/c5ra22248f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We present a nanocalorimetric platform for accurate thermochemical studies of (bio-)chemical reactions in a miniaturized format, characterized by fast thermalization time, excellent base temperature stability and fast sensing response time.
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Affiliation(s)
- Rima Padovani
- Laboratory of Microsystems
- Ecole Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne
- Switzerland
| | - Thomas Lehnert
- Laboratory of Microsystems
- Ecole Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne
- Switzerland
| | - Raphaël Trouillon
- Laboratory of Microsystems
- Ecole Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne
- Switzerland
| | - Martin A. M. Gijs
- Laboratory of Microsystems
- Ecole Polytechnique Fédérale de Lausanne
- CH-1015 Lausanne
- Switzerland
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44
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Maskow T, Paufler S. What does calorimetry and thermodynamics of living cells tell us? Methods 2014; 76:3-10. [PMID: 25461814 DOI: 10.1016/j.ymeth.2014.10.035] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 10/23/2014] [Accepted: 10/28/2014] [Indexed: 02/08/2023] Open
Abstract
This article presents and compares several thermodynamic methods for the quantitative interpretation of data from calorimetric measurements. Heat generation and absorption are universal features of microbial growth and product formation as well as of cell cultures from animals, plants and insects. The heat production rate reflects metabolic changes in real time and is measurable on-line. The detection limit of commercially available calorimetric instruments can be low enough to measure the heat of 100,000 aerobically growing bacteria or of 100 myocardial cells. Heat can be monitored in reaction vessels ranging from a few nanoliters up to many cubic meters. Most important the heat flux measurement does not interfere with the biological process under investigation. The practical advantages of calorimetry include the waiver of labeling and reactants. It is further possible to assemble the thermal transducer in a protected way that reduces aging and thereby signal drifts. Calorimetry works with optically opaque solutions. All of these advantages make calorimetry an interesting method for many applications in medicine, environmental sciences, ecology, biochemistry and biotechnology, just to mention a few. However, in many cases the heat signal is merely used to monitor biological processes but only rarely to quantitatively interpret the data. Therefore, a significant proportion of the information potential of calorimetry remains unutilized. To fill this information gap and to motivate the reader using the full information potential of calorimetry, various methods for quantitative data interpretations are presented, evaluated and compared with each other. Possible errors of interpretation and limitations of quantitative data analysis are also discussed.
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Affiliation(s)
- Thomas Maskow
- UFZ, Helmholtz Centre for Environmental Research, Dept. Environmental Microbiology, Permoserstr. 15, D-04318 Leipzig, Germany.
| | - Sven Paufler
- UFZ, Helmholtz Centre for Environmental Research, Dept. Environmental Microbiology, Permoserstr. 15, D-04318 Leipzig, Germany.
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45
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Dechaumphai E, Chen R. Sub-picowatt resolution calorimetry with niobium nitride thin-film thermometer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:094903. [PMID: 25273760 DOI: 10.1063/1.4895678] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
High-resolution calorimetry has many important applications such as probing nanoscale thermal transport and studying the thermodynamics of biological and chemical systems. In this work, we demonstrated a calorimeter with an unprecedentedly high resolution at room temperature using a high-performance resistive thermometry material, niobium nitride (NbN(x)). Based on a theoretical analysis, we first showed that the heat flux resolution of a resistive-thermometry based calorimeter depends on the parasitic thermal conductance of the device and the temperature coefficient of resistance (TCR) of the thermometer, when the noise is limited by the Johnson noise. Based on this analysis, we then developed a calorimeter using NbNx as the thermometry material because it possesses both high TCR (~0.67%/K) and a low thermal conductivity (k ~ 1.1 W/m K). This calorimeter, when used with the modulated heating scheme, demonstrated an unprecedentedly high power resolution of 0.26 pW at room temperature. In addition, NbNx based resistive thermometry can also be extended to cryogenic temperature, where the TCR is shown to be significantly higher.
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Affiliation(s)
- Edward Dechaumphai
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, USA
| | - Renkun Chen
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, USA
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46
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Davaji B, Jeong Bak H, Chang WJ, Hoon Lee C. A novel on-chip three-dimensional micromachined calorimeter with fully enclosed and suspended thin-film chamber for thermal characterization of liquid samples. BIOMICROFLUIDICS 2014; 8:034101. [PMID: 24926386 PMCID: PMC4032420 DOI: 10.1063/1.4875656] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 04/29/2014] [Indexed: 05/02/2023]
Abstract
A microfabricated calorimeter (μ-calorimeter) with an enclosed reaction chamber is presented. The 3D micromachined reaction chamber is capable of analyzing liquid samples with volume of 200 nl. The thin film low-stress silicon nitride membrane is used to reduce thermal mass of the calorimeter and increase the sensitivity of system. The μ-calorimeter has been designed to perform DC and AC calorimetry, thermal wave analysis, and differential scanning calorimetry. The μ-calorimeter fabricated with an integrated heater and a temperature sensor on opposite sides of the reaction chamber allows to perform thermal diffusivity and specific heat measurements on liquid samples with same device. Measurement results for diffusivity and heat capacitance using time delay method and thermal wave analysis are presented.
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Affiliation(s)
- Benyamin Davaji
- Nanoscale Devices Laboratory, Marquette University, Milwaukee, Wisconsin 53233, USA
| | - Hye Jeong Bak
- Nanoscale Devices Laboratory, Marquette University, Milwaukee, Wisconsin 53233, USA
| | - Woo-Jin Chang
- University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Chung Hoon Lee
- Nanoscale Devices Laboratory, Marquette University, Milwaukee, Wisconsin 53233, USA
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Kim K, Xu X, Guo J, Fan DL. Ultrahigh-speed rotating nanoelectromechanical system devices assembled from nanoscale building blocks. Nat Commun 2014; 5:3632. [DOI: 10.1038/ncomms4632] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/12/2014] [Indexed: 12/23/2022] Open
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Ahumada O, Pérez-Madrigal MM, Ramirez J, Curcó D, Esteves C, Salvador-Matar A, Luongo G, Armelin E, Puiggalí J, Alemán C. Sensitive thermal transitions of nanoscale polymer samples using the bimetallic effect: application to ultra-thin polythiophene. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:053904. [PMID: 23742563 DOI: 10.1063/1.4804395] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A sensitive nanocalorimetric technology based on microcantilever sensors is presented. The technology, which combines very short response times with very small sample consumption, uses the bimetallic effect to detect thermal transitions. Specifically, abrupt variations in the Young's modulus and the thermal expansion coefficient produced by temperature changes have been employed to detect thermodynamic transitions. The technology has been used to determine the glass transition of poly(3-thiophene methyl acetate), a soluble semiconducting polymer with different nanotechnological applications. The glass transition temperature determined using microcantilevers coated with ultra-thin films of mass = 10(-13) g is 5.2 °C higher than that obtained using a conventional differential scanning calorimeter for bulk powder samples of mass = 5 × 10(-3) g. Atomistic molecular dynamics simulations on models that represent the bulk powder and the ultra-thin films have been carried out to provide understanding and rationalization of this feature. Simulations indicate that the film-air interface plays a crucial role in films with very small thickness, affecting both the organization of the molecular chains and the response of the molecules against the temperature.
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Affiliation(s)
- O Ahumada
- Mecwins S.L., Parque Científico de Madrid PTM, C/Santiago Grisolía 2, Tres Cantos, Madrid E-28760, Spain.
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Pagliara S, Chimerel C, Langford R, Aarts DGAL, Keyser UF. Parallel sub-micrometre channels with different dimensions for laser scattering detection. LAB ON A CHIP 2011; 11:3365-3368. [PMID: 21804971 DOI: 10.1039/c1lc20399a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A novel and simple approach for the realization of polymer sub-micrometre channels is introduced by exploiting replica molding of Pt wires deposited by focused ion beam. We fabricate arrays of parallel channels with typical dimensions down to 600 nm and with variable height. We characterize the pressure-driven transport of polymer colloids through the channels in terms of the translocation frequency, amplitude and duration by implementing a laser scattering detection technique. We propose a prototype application of the presented platform such as the in situ sizing and sensing of populations of particles with different dimensions down to 50 nm.
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Affiliation(s)
- Stefano Pagliara
- University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, United Kingdom
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Lubbers B, Baudenbacher F. Isothermal titration calorimetry in nanoliter droplets with subsecond time constants. Anal Chem 2011; 83:7955-61. [PMID: 21913688 DOI: 10.1021/ac202026a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We reduced the reaction volume in microfabricated suspended-membrane titration calorimeters to nanoliter droplets and improved the sensitivities to below a nanowatt with time constants of around 100 ms. The device performance was characterized using exothermic acid-base neutralizations and a detailed numerical model. The finite element based numerical model allowed us to determine the sensitivities within 1% and the temporal dynamics of the temperature rise in neutralization reactions as a function of droplet size. The model was used to determine the optimum calorimeter design (membrane size and thickness, junction area, and thermopile thickness) and sensitivities for sample volumes of 1 nL for silicon nitride and polymer membranes. We obtained a maximum sensitivity of 153 pW/(Hz)(1/2) for a 1 μm SiN membrane and 79 pW/(Hz)(1/2) for a 1 μm polymer membrane. The time constant of the calorimeter system was determined experimentally using a pulsed laser to increase the temperature of nanoliter sample volumes. For a 2.5 nanoliter sample volume, we experimentally determined a noise equivalent power of 500 pW/(Hz)(1/2) and a 1/e time constant of 110 ms for a modified commercially available infrared sensor with a thin-film thermopile. Furthermore, we demonstrated detection of 1.4 nJ reaction energies from injection of 25 pL of 1 mM HCl into a 2.5 nL droplet of 1 mM NaOH.
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Affiliation(s)
- Brad Lubbers
- Department of Biomedical Engineering, VU Station B 351631, Vanderbilt University, Nashville, Tennessee 37232, USA
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