Article
Chemistry, Analytical
Qiang Zhao, Yunjiao Wang, Bangyong Sun, Deqiang Wang, Gang Li
Summary: This research presents a dielectrophoretic manipulation technique based on nanogap electrodes, which allows for the capture, enrichment, and sorting of nanometer-sized objects in liquids. The technique shows potential applications in micro/nanofluidics and provides an alternative method for the non-invasive manipulation and characterization of nanoparticles such as DNA, proteins, and viruses.
Review
Biochemical Research Methods
Kel S. Hakim, Blanca H. Lapizco-Encinas
Summary: Nonlinear electrokinetics technologies, such as DEP particle trapping and EROT for particle assessments, have been widely applied in the analysis, sensing, and purification of microorganisms. Recent research has made significant advancements in these technologies, showcasing the potential future developments within the field of microscale EK.
Review
Biochemical Research Methods
Blanca H. Lapizco-Encinas
Summary: This review article discusses the evolution of insulator-based dielectrophoresis (iDEP) and insulator-based electrokinetic (iEK) systems, highlighting recent studies that suggest particle trapping in these systems is mainly due to a balance between electroosmotic and electrophoretic effects under DC and low-frequency AC potentials, rather than dielectrophoresis. The proposed renaming of the field from DC-iDEP to DC-iEK reflects the shift in understanding particle manipulation and separation mechanisms in these systems.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Shreyank Goel, Dipin S. Pillai
Summary: This paper investigates the electrowetting behavior of a charge-carrying droplet and develops a reduced-order electrokinetic model. The dependence of droplet deformation and wetting alteration on electric field parameters is studied numerically. The research findings are important for applications such as biomedical diagnostics.
Review
Biophysics
Vahid Kordzadeh-Kermani, Masoud Madadelahi, Seyed Nezameddin Ashrafizadeh, Lawrence Kulinsky, Sergio O. Martinez-Chapa, Marc J. Madou
Summary: This review introduces the on-board power supply and electrokinetic applications of electrified-LOD (eLOD) devices. By utilizing electrokinetic phenomena, different microfluids can be propelled, separated, and manipulated. While extensive research exists on stationary platforms, the applications on rotating platforms are still underdeveloped.
BIOSENSORS & BIOELECTRONICS
(2022)
Article
Chemistry, Analytical
Raul Fernandez-Mateo, Victor Calero, Hywel Morgan, Antonio Ramos, Pablo Garcia-Sanchez
Summary: This paper investigates stationary electroosmotic flows of electrolytes around insulating constrictions induced by low frequency AC electric fields, introducing the concept of concentration-polarization electroosmosis. Experimental results are in qualitative agreement with the model predictions, but trapping of particles in shallow channels is also observed.
ANALYTICAL CHEMISTRY
(2021)
Article
Biochemical Research Methods
Le Song, Liandong Yu, Christian Brumme, Ryan Shaw, Cheng Zhang, Xiangchun Xuan
Summary: This study presents the first exploration of Joule heating effects in electrokinetic microchannel flows with conductivity gradients, revealing that Joule heating increases the critical electric field for electrokinetic instability and leads to a smaller electric Rayleigh number.
Article
Chemistry, Analytical
Taekeon Jung, Young-Ran Yun, Jaehyun Bae, Sung Yang
Summary: By integrating magnetic particle conjugation for bacteria concentration and separation, a new impedimetric bacteria-detection sensor has been developed for rapid and accurate detection of low bacteria concentrations in food samples.
ANALYTICA CHIMICA ACTA
(2021)
Article
Chemistry, Analytical
Maria Dimaki, Mark Holm Olsen, Noemi Rozlosnik, Winnie E. Svendsen
Summary: This paper introduces a novel microfluidic chip that utilizes electrical forces generated by a DC or AC field to achieve upconcentration of sub-100 nm nanoparticles in a flow. Two optimized electrode designs were tested using particles as small as 47 nm, and inclined electrodes with a zig-zag three-tooth configuration in a 20 μm width channel were found to generate the highest gradient and force. The chip design based on AC dielectrophoresis successfully upconcentrated sub-100 nm particles by a factor of 11 using a flow rate of 2-25 μL/h. The paper presents theoretical and experimental results, and discusses the potential for massively parallelizing the chip design to significantly increase throughput.
Article
Nanoscience & Nanotechnology
Tom Elkeles, Sinwook Park, Jorg G. Werner, David A. Weitz, Gilad Yossifon
Summary: This work presents the dielectrophoresis and in situ electrorotation characterization of reversible stimuli-responsive dynamic microcapsules that can change their physicochemical properties under varying pH conditions. The study shows that the conductivity of the capsules' shells is most influenced by pH and provides insight into the characteristic time scales of physical processes through transient response measurements. Additionally, the magnetic manipulation of microcapsules with embedded magnetic nanoparticles for lab-on-chip tasks is demonstrated, along with the on-chip determination of their physicochemical state using electrorotation.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Mechanics
Kaushlendra Dubey, Sanjeev Sanghi, Amit Gupta, Supreet Singh Bahga
Summary: The study investigates the electrokinetic instability (EKI) in microchannel flow with streamwise conductivity gradients, commonly seen during sample stacking in capillary electrophoresis. Through experiments and numerical simulations, the researchers demonstrate how non-uniform electroosmotic flow in areas of varying conductivity can lead to instability above a threshold electric field. The simulations align well with experimental observations, providing insight into the underlying mechanism of the instability.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Xiangzhi Zhang, Xiawei Xu, Yong Ren, Yuying Yan, Aiguo Wu
Summary: An Y-Y shaped microfluidic device was designed to separate NSCLC cells using a dielectrophoresis approach, with a separation efficiency of around 99% achieved under optimal operating conditions. This study presents a potentially efficient, facile, and low-cost route for circulating tumor cell separation, which was optimized through numerical simulations.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Review
Biochemical Research Methods
Jared P. Smithers, Mark A. Hayes
Summary: The development of microfluidic manipulations has led to significant advances in the processing and detection of small volume samples. Effective isolation of single cells and manipulation of complex biomolecule mixtures allows for the utilization of information-rich detection methods. Delivering sub-nanoliter volumes of samples to a detection scheme has been achieved through spraying, meniscus-defined volumes, constrained volumes, and phase changes. This review presents selected publications highlighting the advancements and historical perspectives of these delivery techniques.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Mechanics
Zhaodong Ding, Yongjun Jian
Summary: The study focused on the electrokinetic flow of viscoelastic fluids under oscillatory pressure gradients, finding resonance effects when elastic properties dominate. By analyzing the interaction of viscoelastic shear waves, the critical Deborah number for resonance was derived. Different fluid models were used to investigate efficiency enhancement and damping effects, providing insights into the occurrence of resonances under various conditions.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Chemistry, Analytical
Bao D. Ho, Jason P. Beech, Jonas O. Tegenfeldt
Summary: By combining deterministic lateral displacement (DLD) with electrokinetics, this study demonstrates the sorting of cells based on differences in membrane and/or internal structures, and successfully separates different cell types in experiments. The significant change in zeta potential or dielectrophoretic mobility at different frequencies is utilized to achieve cell separation.
Article
Chemistry, Analytical
Qi Chen, Di Li, Amirreza Malekanfard, Quanliang Cao, Jianhan Lin, Maohua Wang, Xiaotao Han, Xiangchun Xuan
ANALYTICAL CHEMISTRY
(2018)
Article
Biochemical Research Methods
Chien-Hsuan Ko, Di Li, Amirreza Malekanfard, Yao-Nan Wang, Lung-Ming Fu, Xiangchun Xuan
Article
Mechanics
Amirreza Malekanfard, Chien-Hsuan Ko, Di Li, Logan Bulloch, Alicia Baldwin, Yao-Nan Wang, Lung-Ming Fu, Xiangchun Xuan
Article
Chemistry, Analytical
Song-Yu Lu, Amirreza Malekanfard, Shayesteh Beladi-Behbahani, Wuzhou Zu, Akshay Kale, Tzuen-Rong Tzeng, Yao-Nan Wang, Xiangchun Xuan
Article
Chemistry, Analytical
Akshay Kale, Amirreza Malekanfard, Xiangchun Xuan
Article
Chemistry, Analytical
Amirreza Malekanfard, Shayesteh Beladi-Behbahani, Tzuen-Rong Tzeng, Hui Zhao, Xiangchun Xuan
Summary: This study introduces a technique for particle/cell focusing using low-frequency AC electric fields, demonstrating its effectiveness compared to DC iDEP focusing with a second-order power relationship for improved efficiency. The AC iDEP focusing method eliminates the need for large electric fields and small constrictions, offering better performance benefits.
ANALYTICAL CHEMISTRY
(2021)
Article
Biochemical Research Methods
Joseph Bentor, Amirreza Malekanfard, Mahmud Kamal Raihan, Sen Wu, Xinxiang Pan, Yongxin Song, Xiangchun Xuan
Summary: Experimental study shows that rheological properties of fluids significantly impact the focusing and trapping effects in iDEP microdevices. Strongly viscoelastic polyacrylamide solution demonstrates the best performance, while xanthan gum solution is not suitable for iDEP focusing.
Article
Physics, Fluids & Plasmas
Amirreza Malekanfard, Zhijian Liu, Hui Zhao, Yongxin Song, Xiangchun Xuan
Summary: Insulator-based dielectrophoresis (iDEP) is a emerging technique for particle manipulation in microfluidic devices, where induced charge electroosmisis (ICEO) and electrothermal flow (ETF) exhibit different strength vortex patterns in low and high electric conductivity fluids, but become marginal in moderate-concentration buffers due to opposing effects of ICEO and ETF.
PHYSICAL REVIEW FLUIDS
(2021)