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Yuan Y, Zhang J, Zhang L, Yin W, Zhang S, Chen T, Li Z, Ding C, Cheng H, Wang A, Chen F. Frequency-modulated alternating current-driven bioelectrodes for enhanced mineralization of Alizarin Yellow R. JOURNAL OF HAZARDOUS MATERIALS 2024; 475:134906. [PMID: 38889455 DOI: 10.1016/j.jhazmat.2024.134906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/18/2024] [Accepted: 06/12/2024] [Indexed: 06/20/2024]
Abstract
The alternating current (AC)-driven bioelectrochemical process, in-situ coupling cathodic reduction and anodic oxidation in a single electrode, offers a promising way for the mineralization of refractory aromatic pollutants (RAPs). Frequency modulation is vital for aligning reduction and oxidation phases in AC-driven bioelectrodes, potentially enhancing their capability to mineralize RAPs. Herein, a frequency-modulated AC-driven bioelectrode was developed to enhance RAP mineralization, exemplified by the degradation of Alizarin Yellow R (AYR). Optimal performance was achieved at a frequency of 1.67 mHz, resulting in the highest efficiency for AYR decolorization and subsequent mineralization of intermediates. Performance declined at both higher (3.33 and 8.30 mHz) and lower (0.83 mHz) frequencies. The bioelectrode exhibited superior electron utilization, bidirectional electron transfer, and redox bifunctionality, effectively aligning reduction and oxidation processes to enhance AYR mineralization. The 1.67 mHz frequency facilitated the assembly of a collaborative microbiome dedicated to AYR bio-mineralization, characterized by an increased abundance of functional consortia proficient in azo dye reduction (e.g., Stenotrophomonas and Shinella), aromatic intermediates oxidation (e.g., Sphingopyxis and Sphingomonas), and electron transfer (e.g., Geobacter and Pseudomonas). This study reveals the role of frequency modulation in AC-driven bioelectrodes for enhanced RAP mineralization, offering a novel and sustainable approach for treating RAP-bearing wastewater.
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Affiliation(s)
- Ye Yuan
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Junjie Zhang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Lulu Zhang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Wanxin Yin
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Shihan Zhang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Tianming Chen
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Zhaoxia Li
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Cheng Ding
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Haoyi Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, PR China
| | - Aijie Wang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, PR China.
| | - Fan Chen
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China; Shaanxi Key Laboratory of Qinling Ecological Intelligent Monitoring and Protection, School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710129, PR China.
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Taale M, Schamberger B, Monclus MA, Dolle C, Taheri F, Mager D, Eggeler YM, Korvink JG, Molina-Aldareguia JM, Selhuber-Unkel C, Lantada AD, Islam M. Microarchitected Compliant Scaffolds of Pyrolytic Carbon for 3D Muscle Cell Growth. Adv Healthc Mater 2024; 13:e2303485. [PMID: 38150609 DOI: 10.1002/adhm.202303485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Indexed: 12/29/2023]
Abstract
The integration of additive manufacturing technologies with the pyrolysis of polymeric precursors enables the design-controlled fabrication of architected 3D pyrolytic carbon (PyC) structures with complex architectural details. Despite great promise, their use in cellular interaction remains unexplored. This study pioneers the utilization of microarchitected 3D PyC structures as biocompatible scaffolds for the colonization of muscle cells in a 3D environment. PyC scaffolds are fabricated using micro-stereolithography, followed by pyrolysis. Furthermore, an innovative design strategy using revolute joints is employed to obtain novel, compliant structures of architected PyC. The pyrolysis process results in a pyrolysis temperature- and design-geometry-dependent shrinkage of up to 73%, enabling the geometrical features of microarchitected compatible with skeletal muscle cells. The stiffness of architected PyC varies with the pyrolysis temperature, with the highest value of 29.57 ± 0.78 GPa for 900 °C. The PyC scaffolds exhibit excellent biocompatibility and yield 3D cell colonization while culturing skeletal muscle C2C12 cells. They further induce good actin fiber alignment along the compliant PyC construction. However, no conclusive myogenic differentiation is observed here. Nevertheless, these results are highly promising for architected PyC scaffolds as multifunctional tissue implants and encourage more investigations in employing compliant architected PyC structures for high-performance tissue engineering applications.
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Affiliation(s)
- Mohammadreza Taale
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), Heidelberg University, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Barbara Schamberger
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), Heidelberg University, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | | | - Christian Dolle
- Microscopy of Nanoscale Structures and Mechanisms (MNM), Laboratory for Electron Microscopy (LEM), Karlsruhe Institute of Technology, Engesserstr. 7, D-76131, Karlsruhe, Germany
| | - Fereydoon Taheri
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), Heidelberg University, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Dario Mager
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
| | - Yolita M Eggeler
- Microscopy of Nanoscale Structures and Mechanisms (MNM), Laboratory for Electron Microscopy (LEM), Karlsruhe Institute of Technology, Engesserstr. 7, D-76131, Karlsruhe, Germany
| | - Jan G Korvink
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
| | - Jon M Molina-Aldareguia
- IMDEA Materials Institute, Eric Kandel, 2, Getafe, 28906, Spain
- Department of Mechanical Engineering, Universidad Politécnica de Madrid, José Gutierréz Abascal, 2, Madrid, 28006, Spain
| | - Christine Selhuber-Unkel
- Institute for Molecular Systems Engineering and Advanced Materials (IMSEAM), Heidelberg University, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany
| | - Andrés Díaz Lantada
- Department of Mechanical Engineering, Universidad Politécnica de Madrid, José Gutierréz Abascal, 2, Madrid, 28006, Spain
| | - Monsur Islam
- IMDEA Materials Institute, Eric Kandel, 2, Getafe, 28906, Spain
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
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Feng X, Wang T, Jiang Y, Liu Y, Yang H, Duan Z, Ji L, Wei J. Cerebral Theta-Burst Stimulation Combined with Physiotherapy in Patients with Incomplete Spinal Cord Injury: A Pilot Randomized Controlled Trial. J Rehabil Med 2023; 55:jrm00375. [PMID: 36779636 PMCID: PMC9941982 DOI: 10.2340/jrm.v55.4375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 01/04/2023] [Indexed: 02/14/2023] Open
Abstract
OBJECTIVE To measure the effects of cerebral intermittent theta-burst stimulation with physiotherapy on lower extremity motor recovery in patients with incomplete spinal cord injury. DESIGN Randomized, double-blinded, sham-controlled trial. SUBJECTS Adults with incomplete spinal cord injury. METHODS A total of 38 patients with incomplete spinal cord injury were randomized into either an intermittent theta-burst stimulation or a sham group. Both groups participated in physiotherapy 5 times per week for 9 weeks, and cerebral intermittent theta-burst stimulation or sham intermittent theta-burst stimulation was performed daily, immediately before physiotherapy. The primary outcomes were lower extremity motor score (LEMS), root-mean square (RMS), RMS of the quadriceps femoris muscle, walking speed (WS), and stride length (SL). Secondary outcomes comprised Holden Walking Ability Scale (HWAS) and modified Barthel Index (MBI). The outcomes were assessed before the intervention and 9 weeks after the start of the intervention. RESULTS Nine weeks of cerebral intermittent theta-burst stimulation with physiotherapy intervention resulted in improved recovery of lower extremity motor recovery in patients with incomplete spinal cord injury. Compared with baseline, the changes in LEMS, WS, SL, RMS, HWAS, and MBI were significant in both groups after intervention. The LEMS, WS, SL, RMS, HWAS, and MBI scores were improved more in the intermittent theta-burst stimulation group than in the sham group. CONCLUSION Cerebral intermittent theta-burst stimulation with physiotherapy promotes lower extremity motor recovery in patients with incomplete spinal cord injury. However, this study included a small sample size and lacked a comparison of the treatment effects of multiple stimulation modes, the further research will be required in the future.
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Affiliation(s)
- Xiaojun Feng
- Department of Rehabilitation Medicine; Research Center for Translational Medicine, The Second Hospital of Anhui Medical University, Hefei City, Anhui Province; Department of Rehabilitation Medicine, The Fuyang Hospital of Anhui Medical University, Fuyang City, Anhui Province, China.
| | - Tingting Wang
- Department of Rehabilitation Medicine; Research Center for Translational Medicine, The Second Hospital of Anhui Medical University, Hefei City, Anhui Province; Department of Rehabilitation Medicine, The Fuyang Hospital of Anhui Medical University, Fuyang City, Anhui Province, China
| | - Yan Jiang
- Department of Rehabilitation Medicine
| | - Yi Liu
- Department of Rehabilitation Medicine
| | - Haifeng Yang
- Department of Rehabilitation Medicine, The Fuyang Hospital of Anhui Medical University, Fuyang City, Anhui Province, China
| | - Zongyu Duan
- Department of Rehabilitation Medicine, The Fuyang Hospital of Anhui Medical University, Fuyang City, Anhui Province, China
| | - Leilei Ji
- Department of Rehabilitation Medicine
| | - Juan Wei
- Department of Rehabilitation Medicine
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Monitoring Technology of Abnormal Displacement of BeiDou Power Line Based on Artificial Neural Network. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2022; 2022:7623215. [PMID: 36093483 PMCID: PMC9452940 DOI: 10.1155/2022/7623215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/23/2022] [Indexed: 11/29/2022]
Abstract
In the practice of power line engineering, navigation and positioning technology is often used in the fields of information collection and analysis, optimized line design, and deformation monitoring. Compared with traditional measurement technology, it has the characteristics of high precision and high reliability. In order to realize the measurement of abnormal displacement of power lines, improve the efficiency and quality of monitoring, and reduce the occurrence of faults, firstly, this study introduces the basic theory of artificial neural network (ANN). The core algorithm of the ANN-BP (back propagation) neural network has been improved. The improved algorithm is used to improve the BeiDou Navigation Satellite System (BDS). The improved and the unimproved BDS are used to solve the collected related data. The results show that the geometric dilution of precision (GDOP) values obtained by conventional BDS are small, all within the range of less than 4. After the introduction of the BP neural network into the system, the geometric space distribution of positioning satellites is improved, the GDOP is reduced, the reliability and availability of satellite positioning are enhanced, and the accuracy requirements are met. The accuracy of the measured data positioning results of the two systems has reached the cm level. There is not much difference between the processing results of the two modes. Among them, the Z direction accuracy has the largest difference, which is 2.5 cm. The introduction of the BP neural network has improved the spatial combination structure, and the positioning results in the three directions of X, Y, and Z are all better. From the perspective of root mean square (RMS), the RMS fluctuation of the simulation results obtained by observing the conventional BDS is large. The RMS value of BDS displacement based on the BP neural network is smaller, and the change is gentle. With the increase in the number of epochs and the increase in the number of simulations, its value is also more convergent. These data show that the quality of BDS observations based on the BP neural network is significantly better. These contents will effectively improve the monitoring accuracy and operational reliability of the system and have important practical significance and application value.
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Pahar M, Miranda I, Diacon A, Niesler T. Automatic Non-Invasive Cough Detection based on Accelerometer and Audio Signals. JOURNAL OF SIGNAL PROCESSING SYSTEMS 2022; 94:821-835. [PMID: 35341095 PMCID: PMC8934184 DOI: 10.1007/s11265-022-01748-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 01/09/2022] [Accepted: 02/23/2022] [Indexed: 12/01/2022]
Abstract
We present an automatic non-invasive way of detecting cough events based on both accelerometer and audio signals. The acceleration signals are captured by a smartphone firmly attached to the patient’s bed, using its integrated accelerometer. The audio signals are captured simultaneously by the same smartphone using an external microphone. We have compiled a manually-annotated dataset containing such simultaneously-captured acceleration and audio signals for approximately 6000 cough and 68000 non-cough events from 14 adult male patients. Logistic regression (LR), support vector machine (SVM) and multilayer perceptron (MLP) classifiers provide a baseline and are compared with three deep architectures, convolutional neural network (CNN), long short-term memory (LSTM) network, and residual-based architecture (Resnet50) using a leave-one-out cross-validation scheme. We find that it is possible to use either acceleration or audio signals to distinguish between coughing and other activities including sneezing, throat-clearing, and movement on the bed with high accuracy. However, in all cases, the deep neural networks outperform the shallow classifiers by a clear margin and the Resnet50 offers the best performance, achieving an area under the ROC curve (AUC) exceeding 0.98 and 0.99 for acceleration and audio signals respectively. While audio-based classification consistently offers better performance than acceleration-based classification, we observe that the difference is very small for the best systems. Since the acceleration signal requires less processing power, and since the need to record audio is sidestepped and thus privacy is inherently secured, and since the recording device is attached to the bed and not worn, an accelerometer-based highly accurate non-invasive cough detector may represent a more convenient and readily accepted method in long-term cough monitoring.
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Affiliation(s)
- Madhurananda Pahar
- Department of Electrical and Electronic Engineering, Stellenbosch University, Stellenbosch, 7600 Western Cape South Africa
| | - Igor Miranda
- Federal University of Recôncavo da Bahia, Cruz das Almas, 44.380-000 Bahia Brazil
| | - Andreas Diacon
- TASK Applied Science, Cape Town, Western Cape South Africa
| | - Thomas Niesler
- Department of Electrical and Electronic Engineering, Stellenbosch University, Stellenbosch, 7600 Western Cape South Africa
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Comparing Carbon Origami from Polyaramid and Cellulose Sheets. MICROMACHINES 2022; 13:mi13040503. [PMID: 35457808 PMCID: PMC9032490 DOI: 10.3390/mi13040503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 12/03/2022]
Abstract
Carbon origami enables the fabrication of lightweight and mechanically stiff 3D complex architectures of carbonaceous materials, which have a high potential to impact a wide range of applications positively. The precursor materials and their inherent microstructure play a crucial role in determining the properties of carbon origami structures. Here, non-porous polyaramid Nomex sheets and macroporous fibril cellulose sheets are explored as the precursor sheets for studying the effect of precursor nature and microstructure on the material and structural properties of the carbon origami structures. The fabrication process involves pre-creasing precursor sheets using a laser engraving process, followed by manual-folding and carbonization. The cellulose precursor experiences a severe structural shrinkage due to its macroporous fibril morphology, compared to the mostly non-porous morphology of Nomex-derived carbon. The morphological differences further yield a higher specific surface area for cellulose-derived carbon. However, Nomex results in more crystalline carbon than cellulose, featuring a turbostratic microstructure like glassy carbon. The combined effect of morphology and glass-like features leads to a high mechanical stiffness of 1.9 ± 0.2 MPa and specific modulus of 2.4 × 104 m2·s−2 for the Nomex-derived carbon Miura-ori structure, which are significantly higher than cellulose-derived carbon Miura-ori (elastic modulus = 504.7 ± 88.2 kPa; specific modulus = 1.2 × 104 m2·s−2) and other carbonaceous origami structures reported in the literature. The results presented here are promising to expand the material library for carbon origami, which will help in the choice of suitable precursor and carbon materials for specific applications.
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Mondal K, Islam M, Singh S, Sharma A. Fabrication of High Surface Area Microporous ZnO from ZnO/Carbon Sacrificial Composite Monolith Template. MICROMACHINES 2022; 13:335. [PMID: 35208458 PMCID: PMC8879774 DOI: 10.3390/mi13020335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 02/05/2023]
Abstract
Fabrication of porous materials from the standard sacrificial template method allows metal oxide nanostructures to be produced and have several applications in energy, filtration and constructing sensing devices. However, the low surface area of these nanostructures is a significant drawback for most applications. Here, we report the synthesis of ZnO/carbon composite monoliths in which carbon is used as a sacrificial template to produce zinc oxide (ZnO) porous nanostructures with a high specific surface area. The synthesized porous oxides of ZnO with a specific surface area of 78 m2/g are at least one order of magnitude higher than that of the ZnO nanotubes reported in the literature. The crucial point to achieving this remarkable result was the usage of a novel ZnO/carbon template where the carbon template was removed by simple heating in the air. As a high surface area porous nanostructured ZnO, these synthesized materials can be useful in various applications including catalysis, photocatalysis, separation, sensing, solar energy harvest and Zn-ion battery and as supercapacitors for energy storage.
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Affiliation(s)
- Kunal Mondal
- Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, Uttar Pradesh, India;
- Materials Science and Engineering Department, Energy and Environment Science and Technology Directorate, Idaho National Laboratory, Idaho Falls, ID 83415, USA
| | - Monsur Islam
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;
| | - Srujan Singh
- Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, Uttar Pradesh, India;
| | - Ashutosh Sharma
- Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, Uttar Pradesh, India;
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Dielectrophoretic Manipulation of Cell Transfection Efficiency during Electroporation Using a Center Needle Electrode. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11157015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Long duration electric pulses are frequently used to facilitate DNA electrotransfer into cells and tissues, while electroporation pulses can be combined with electrophoresis to maximize the transfection efficiency. In this work, we present the dielectrophoresis (DEP)-assisted methodology for electrotransfer of plasmid DNA (3.5 kbp pmaxGFP) into mammalian cells (CHO-K1). A prototype of an electroporation cuvette with center needle electrode for DEP-assisted transfection is presented resulting in a 1.4-fold of transfection efficiency increase compared to the electroporation-only procedure (1.4 kV/cm × 100 µs × 8). The efficiency of transfection has been compared between three DEP frequencies of 1, 100, and 1 MHz. Lastly, the effects of exposure time (1, 3, and 5 min) during the DEP application step have been determined. It is concluded that the proposed methodology and exposure setup allow a significant improvement of transfection efficiency and could be used as an alternative to the currently popular electrotransfection techniques.
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Ramirez-Murillo CJ, de Los Santos-Ramirez JM, Perez-Gonzalez VH. Toward low-voltage dielectrophoresis-based microfluidic systems: A review. Electrophoresis 2020; 42:565-587. [PMID: 33166414 DOI: 10.1002/elps.202000213] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 10/27/2020] [Accepted: 11/02/2020] [Indexed: 12/13/2022]
Abstract
Dielectrophoretically driven microfluidic devices have demonstrated great applicability in biomedical engineering, diagnostic medicine, and biological research. One of the potential fields of application for this technology is in point-of-care (POC) devices, ideally allowing for portable, fully integrated, easy to use, low-cost diagnostic platforms. Two main approaches exist to induce dielectrophoresis (DEP) on suspended particles, that is, electrode-based DEP and insulator-based DEP, each featuring different advantages and disadvantages. However, a shared concern lies in the input voltage used to generate the electric field necessary for DEP to take place. Therefore, input voltage can determine portability of a microfluidic device. This review outlines the recent advances in reducing stimulation voltage requirements in DEP-driven microfluidics.
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Characterization of the Dielectrophoretic Response of Different Candida Strains Using 3D Carbon Microelectrodes. MICROMACHINES 2020; 11:mi11030255. [PMID: 32121163 PMCID: PMC7143313 DOI: 10.3390/mi11030255] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/23/2020] [Accepted: 02/26/2020] [Indexed: 02/08/2023]
Abstract
Bloodstream infection with Candida fungal cells remains one of the most life-threatening complications among hospitalized patients around the world. Although most of the cases are still due to Candida albicans, the rising incidence of infections caused by other Candida strains that may not respond to traditional anti-fungal treatments merits the development of a method for species-specific isolation of Candida. To this end, here we present the characterization of the dielectrophoresis (DEP) response of Candida albicans, Candida tropicalis and Candida parapsilosis. We complement such characterization with a study of the Candida cells morphology. The Candida strains exhibited subtle differences in their morphology and dimensions. All the Candida strains exhibited positive DEP in the range 10-500 kHz, although the strength of the DEP response was different for each Candida strain at different frequencies. Only Candida tropicalis showed positive DEP at 750 kHz. The current results show potential for manipulation and enrichment of a specific Candida strain at specific DEP conditions towards aiding in the rapid identification of Candida strains to enable the effective and timely treatment of Candida infections.
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Natu R, Islam M, Keck D, Martinez-Duarte R. Automated "pick and transfer" of targeted cells using dielectrophoresis. LAB ON A CHIP 2019; 19:2512-2525. [PMID: 31259984 DOI: 10.1039/c9lc00409b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Selective manipulation of single cells is an important step in sample preparation for biological analysis. A highly specific and automated device is desired for such an operation. An ideal device would be able to selectively pick several single cells in parallel from a heterogeneous population and transfer those to designated sites for further analysis without human intervention. The robotic manipulator developed here provides the basis for development of such a device. The device in this work is designed to selectively pick cells based on their inherent properties using dielectrophoresis (DEP) and automatically transfer and release those at a transfer site. Here we provide proof of concept of such a device and study the effect of different parameters on its operation. Successful experiments were conducted to separate Candida cells from a mixture with 10 μm latex particles and a viability assay was performed for separation of viable rat adipose stem cells (RASCs) from non-viable ones. The robotic DEP device was further used to pick and transfer single RASCs. This work also discusses the advantages and disadvantages of our current setup and illustrates the future steps required to improve the performance of this robotic DEP technology.
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Affiliation(s)
- Rucha Natu
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering, Clemson University, SC 29634, USA.
| | - Monsur Islam
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering, Clemson University, SC 29634, USA. and Karlsruhe Institute of Technology, Institute of Microstructure Technology, Hermann-von-Helmholtz-Platz 1 76344, Eggenstein-Leopoldshafen, Germany
| | - Devin Keck
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering, Clemson University, SC 29634, USA.
| | - Rodrigo Martinez-Duarte
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering, Clemson University, SC 29634, USA.
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Natu R, Islam M, Martinez-Duarte R. Nondimensional Streaming Dielectrophoresis Number for a System of Continuous Particle Separation. Anal Chem 2019; 91:4357-4367. [PMID: 30827100 DOI: 10.1021/acs.analchem.8b04599] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cell sorting methods are required in numerous healthcare assays. Although flow cytometry and magnetically actuated sorting are widespread techniques for cell sorting, there is intense research on label-free techniques to reduce the cost and complexity of the process. Among label-free techniques, dielectrophoresis (DEP) offers the capability to separate cells not only on the basis of size but also on their membrane capacitance. This is important because it enables cell discrimination on the basis of specific traits such as viability, identity, fate, and age. StreamingDEP refers to the continuous sorting of cells thanks to the generation of streams of targeted particles by equilibrating the drag and DEP forces acting on targeted particles. In this work, we provide an analytical expression for a streamingDEP number toward enabling the a priori design of DEP devices to agglomerate targeted particles into streams. The nondimensional streamingDEP number (SDN) obtained in this analysis is applied to experiments with 1 μm polystyrene particles and Candida cells. On the basis of these experiments, three characteristic zones are mapped to different values of the SDN: (1) physical capture thanks to DEP for 0 < SDN < 0.6; (2) streaming due to DEP for 0.6 < SDN < 1; (3) elution without experiencing DEP for SDN > 1.
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Affiliation(s)
- Rucha Natu
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering , Clemson University , Clemson , South Carolina 29634 , United States
| | - Monsur Islam
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering , Clemson University , Clemson , South Carolina 29634 , United States
| | - Rodrigo Martinez-Duarte
- Multiscale Manufacturing Laboratory, Department of Mechanical Engineering , Clemson University , Clemson , South Carolina 29634 , United States
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