scholarly journals Unveiling the Potential of Droplet Generation, Sorting, Expansion, and Restoration in Microfluidic Biochips

Micromachines ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 756
Author(s):  
Yi-Lung Chiu ◽  
Ruchi Ashok Kumar Yadav ◽  
Hong-Yuan Huang ◽  
Yi-Wen Wang ◽  
Da-Jeng Yao

Microfluidic biochip techniques are prominently replacing conventional biochemical analyzers by the integration of all functions necessary for biochemical analysis using microfluidics. The microfluidics of droplets offer exquisite control over the size of microliter samples to satisfy the requirements of embryo culture, which might involve a size ranging from picoliter to nanoliter. Polydimethylsiloxane (PDMS) is the mainstream material for the fabrication of microfluidic devices due to its excellent biocompatibility and simplicity of fabrication. Herein, we developed a microfluidic biomedical chip on a PDMS substrate that integrated four key functions—generation of a droplet of an emulsion, sorting, expansion and restoration, which were employed in a mouse embryo system to assess reproductive medicine. The main channel of the designed chip had width of 1200 μm and height of 500 μm. The designed microfluidic chips possessed six sections—cleaved into three inlets and three outlets—to study the key functions with five-day embryo culture. The control part of the experiment was conducted with polystyrene (PS) beads (100 μm), the same size as the murine embryos, for the purpose of testing. The outcomes of our work illustrate that the rate of success of the static droplet culture group (87.5%) is only slightly less than that of a conventional group (95%). It clearly demonstrates that a droplet-based microfluidic system can produce a droplet in a volume range from picoliter to nanoliter.

Author(s):  
Seyed Ali Tabatabaei ◽  
Mohammad Zabetian Targhi

Isolation of microparticles and biological cells on microfluidic chips has received considerable attention due to their applications in numerous areas such as medical and engineering fields. Microparticles separation is of great importance in bioassays due to the need for smaller sample and device size and lower manufacturing costs. In this study, we first explain the concepts of separation and microfluidic science along with their applications in the medical sciences, and then, a conceptual design of a novel inertial microfluidic system is proposed and analyzed. The PDMS spiral microfluidic device was fabricated, and its effects on the separation of particles with sizes similar to biological particles were experimentally analyzed. This separation technique can be used to separate cancer cells from the normal ones in the blood samples. These components required for testing were selected, assembled, and finally, a very affordable microfluidic kit was provided. Different experiments were designed, and the results were analyzed using appropriate software and methods. Separator system tests with polydisperse hollow glass particles (diameter 2–20 µm), and monodisperse Polystyrene particles (diameter 5 & 15 µm), and the results exhibit an acceptable chip performance with 86% of efficiency for both monodisperse particles and polydisperse particles. The microchannel collects particles with an average diameter of 15.8, 9.4, and 5.9 μm at the proposed reservoirs. This chip can be integrated into a more extensive point-of-care diagnostic system to test blood samples.


1999 ◽  
Author(s):  
Nihat Okulan ◽  
Shekhar Bhansali ◽  
Arum Han ◽  
Saman Dharmatilleke ◽  
Jin-Woo Choi ◽  
...  

Abstract This center is currently working on the development of a remotely accessible generic microfluidic system (“lab on a chip”) for biological and biochemical analysis, based on electrochemical detection techniques. Modular microfluidic components, including micro reservoirs, microvalves, micropumps, filterless magnetic particle separators, biosensors and flowsensors, were fabricated and tested, and integrated on a system motherboard. Other air-to-liquid measurand concentrators and integrated sieve/filters are being explored in related efforts. The fabrication of these microfluidic components and the utilization of wax for low temperature assembly and even bonding is discussed.


Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 297 ◽  
Author(s):  
Kena Song ◽  
Guoqiang Li ◽  
Xiangyang Zu ◽  
Zhe Du ◽  
Liyu Liu ◽  
...  

Microfluidic systems have been widely explored based on microfluidic technology, and it has been widely used for biomedical screening. The key parts are the fabrication of the base scaffold, the construction of the matrix environment in the 3D system, and the application mechanism. In recent years, a variety of new materials have emerged, meanwhile, some new technologies have been developed. In this review, we highlight the properties of high throughput and the biomedical application of the microfluidic chip and focus on the recent progress of the fabrication and application mechanism. The emergence of various biocompatible materials has provided more available raw materials for microfluidic chips. The material is not confined to polydimethylsiloxane (PDMS) and the extracellular microenvironment is not limited by a natural matrix. The mechanism is also developed in diverse ways, including its special physical structure and external field effects, such as dielectrophoresis, magnetophoresis, and acoustophoresis. Furthermore, the cell/organ-based microfluidic system provides a new platform for drug screening due to imitating the anatomic and physiologic properties in vivo. Although microfluidic technology is currently mostly in the laboratory stage, it has great potential for commercial applications in the future.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yushen Zhang ◽  
Tsun-Ming Tseng ◽  
Ulf Schlichtmann

AbstractState-of-the-art microfluidic systems rely on relatively expensive and bulky off-chip infrastructures. The core of a system—the microfluidic chip—requires a clean room and dedicated skills to be fabricated. Thus, state-of-the-art microfluidic systems are barely accessible, especially for the do-it-yourself (DIY) community or enthusiasts. Recent emerging technology—3D-printing—has shown promise to fabricate microfluidic chips more simply, but the resulting chip is mainly hardened and single-layered and can hardly replace the state-of-the-art Polydimethylsiloxane (PDMS) chip. There exists no convenient fluidic control mechanism yet suitable for the hardened single-layered chip, and particularly, the hardened single-layered chip cannot replicate the pneumatic valve—an essential actuator for automatically controlled microfluidics. Instead, 3D-printable non-pneumatic or manually actuated valve designs are reported, but their application is limited. Here, we present a low-cost accessible all-in-one portable microfluidic system, which uses an easy-to-print single-layered 3D-printed microfluidic chip along with a novel active control mechanism for fluids to enable more applications. This active control mechanism is based on air or gas interception and can, e.g., block, direct, and transport fluid. As a demonstration, we show the system can automatically control the fluid in microfluidic chips, which we designed and printed with a consumer-grade 3D-printer. The system is comparably compact and can automatically perform user-programmed experiments. All operations can be done directly on the system with no additional host device required. This work could support the spread of low budget accessible microfluidic systems as portable, usable on-the-go devices and increase the application field of 3D-printed microfluidic devices.


2020 ◽  
Vol 71 (3) ◽  
pp. 2315
Author(s):  
S. SIGÜENZA ◽  
I.S. ÁLVAREZ ◽  
E. MATILLA

Vitrification is the best method for embryo cryopreservation although it increases endogenous reactive oxygen species (ROS) production. N-acetylcysteine (NAC) a free radical scavenger may be used for reducing ROS toxic effects. The aim of the present study is to investigate potential beneficial effects of NAC on the developmental embryo competence applying different culture conditions in vitrified-warmed 2-cell embryos derived in vivo or in vitro. Thus, 2-cell embryos were vitrified or cultured fresh in presence or absence of 1 mM of NAC during: a) the entire embryo culture, b) for 24 hours with NAC at days 1.5 (G1) or 2.5 (G2) and returned to basal embryo culture (KSOM) or c) cultured in the presence of NAC for 12 hours at day 3.5 (G3). Despite NAC addition to fresh or vitrified embryos produced in vivo or by IVF, blastocyst rates remained unchanged. In vitrified-warmed IU or IVF-derived embryos, total cell number varied when NAC was added at day 1.5 although differences were not significant (60.1 ± 1.9 vs. 59.4 ± 1.3 for IU G1 and control respectively; and 59.3 ± 1.6 and 52.6 ± 3.0 IVF G1 and control respectively; mean cell number ± SEM, p > 0.05). It seems that the embryo culture medium supplementation with 1 mM of NAC in the first day after vitrification of development improves blastocyst quality of murine embryos and does not exert any beneficial effect at oyher culture points.


2020 ◽  
Vol 6 (1) ◽  
Author(s):  
A. R. Vollertsen ◽  
D. de Boer ◽  
S. Dekker ◽  
B. A. M. Wesselink ◽  
R. Haverkate ◽  
...  

AbstractMicrofluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing. To achieve this, systems typically integrate all functions into a single, monolithic device as a “one size fits all” solution. However, this approach limits the end users’ (re)design flexibility and complicates the addition of new functions to the system. To address this challenge, we propose and demonstrate a modular and standardized plug-and-play fluidic circuit board (FCB) for operating microfluidic building blocks (MFBBs), whereby both the FCB and the MFBBs contain integrated valves. A single FCB can parallelize up to three MFBBs of the same design or operate MFBBs with entirely different architectures. The operation of the MFBBs through the FCB is fully automated and does not incur the cost of an extra external footprint. We use this modular platform to control three microfluidic large-scale integration (mLSI) MFBBs, each of which features 64 microchambers suitable for cell culturing with high spatiotemporal control. We show as a proof of principle that we can culture human umbilical vein endothelial cells (HUVECs) for multiple days in the chambers of this MFBB. Moreover, we also use the same FCB to control an MFBB for liquid dosing with a high dynamic range. Our results demonstrate that MFBBs with different designs can be controlled and combined on a single FCB. Our novel modular approach to operating an automated microfluidic system for parallelized cell culture will enable greater experimental flexibility and facilitate the cooperation of different chips from different labs.


2013 ◽  
Vol 336-338 ◽  
pp. 80-83
Author(s):  
Ai Liang Zhang ◽  
Xiang Ting Fu ◽  
Yan Zha

A new method for splitting drops on a piezoelectric substrate is presented. An interdigital transducer with the period of 144μm is fabricated on a 128° yx-LiNbO3piezoelectric substrate using microelectric technology. Intermittent surface acoustic wave is generated by an on-to-off radio frequency signal, which is applied to the interdigital transducer, and then radiates into a drop on the acoustic path of the piezoelectric substrate, leading to discontinuous acoustic streaming. A part of the drop is split due to inertia when the surface acoustic wave is suddenly disappeared. Red dye solution drops are demonstrated for fission experiments, and mixture operation of two drops is also implemented using the fission method. Results show that a drop can be split by help of surface acoustic wave, and the distance of two daughters is determined on the volume of the drop. The presented drop fission method provides a new sample preparation technique, which is helpful for microfluidic biochemical analysis in a microfluidic system.


RSC Advances ◽  
2013 ◽  
Vol 3 (48) ◽  
pp. 26451 ◽  
Author(s):  
Telma Cristina Esteves ◽  
Fleur van Rossem ◽  
Verena Nordhoff ◽  
Stefan Schlatt ◽  
Michele Boiani ◽  
...  

2021 ◽  
Author(s):  
Seyed Ali Tabatabaei ◽  
Mohammad Zabetian targhi

Abstract BackgroundIsolation of microparticles and biological cells on microfluidic chips has received considerable attention due to their applications in numerous areas such as medical and engineering fields. Microparticles separation are of great importance in bioassays owing to the need for a smaller sample and device size, and lower manufacturing costs. In this study, we first explain the concepts of separation and microfluidic science along with their applications in the medical sciences, and then, a conceptual design of a novel inertial microfluidic system is proposed and analyzed. The PDMS spiral microfluidic device was fabricated, and its effects on the separation of particles with sizes similar to biological particles were experimentally analyzed. This separation technique can be used in the process of separating cancer cells from the normal ones in the blood samples.ResultsThese components required for testing were selected, assembled, and finally, a very affordable microfluidic kit was provided. Different experiments were designed, and the results were analyzed using appropriate software and methods. Separator system tests with polydisperse hollow glass particles (diameter 2-20 µm), and monodisperse Polystyrene particles (diameter 5,15 µm), and the results exhibit an acceptable chip performance with 86 percent of efficiency for both monodisperse particles and polydisperse particles. The microchannel collects particles with an average diameter of 15.8 μm, 9.4 μm, and 5.9 μm at the Proposed reservoirs. ConclusionThis chip can be integrated into a more extensive point-of-care diagnostic system to test blood samples, and it could be said Based on the results of the experiments, this low-cost and user-friendly setting can be used for a variety of microparticle separation programs such as cell separation in biological assays.


Sign in / Sign up

Export Citation Format

Share Document