This work is financially supported by the Ministry of Science and Technology, Taiwan (Contract no. MOST 103-2113-M-001 -003 -MY2) and the Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taiwan.

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The authors declare that they have no competing financial interests.

وجدنا عملية الانضمام محولات الاكريليك على طبقة 1 من الشريحة MDF إلى أن تكون خادعة. تطبيق فقط 1-2 ميكرولتر من الغراء سوبر كافية وثبتك على محول على رقاقة MDF. أدت كميات أكبر من الغراء في بلمرة غير مكتملة من الغراء عظمى، وعدم الالتزام. مرة واحدة تم الالتزام محولات الاكريليك ب?...

يشار إلى سلوك الخلايا الملتصقة تتحرك باتجاه القطب الموجب أو السالب تحت المباشر التيار الكهربائي الميدان (dcEF) على أنها انجذاب كهربي. سلوك electrotactic الخلايا يلعب دورا هاما في تكوين الجنين، وتجديد الأعصاب، والتئام الجروح. وقد أظهرت 1 الخلايا السرطانية مثل خلايا سرطان البروستاتا الفئران، الخلايا السرطانية 2 الثدي، 3 والرئة خلايا غدية 4-8 الحركة electrotactic تحت dcEF تطبيقها . وقد تم قياس EF الفسيولوجية في أنسجة الغدة. كما تم الإبلاغ عن 9،10 انجذاب كهربي في الخلايا السرطانية، الغدة المرتبطة بها. 2،3 مجتمعة، ويعتبر انجذاب كهربي للخلايا السرطانية أن يكون عاملا ورم خبيث. 11 التحكم في التوجيه الكهربائي الخلايا السرطانية تحت dcEF قد تكون فكرة ممكنة لعلاج السرطان في المستقبل. ومع ذلك، اليوم، آلية جزيئية التفصيلية للانجذاب كهربي لا تزال موضع جدل. لذلك، تحقيقا في الوقود النووي المشعluence من التحفيز الكهربائي على الهجرة الخلايا السرطانية يمكن أن يسهل وضع استراتيجيات لعلاج السرطان. مؤخرا، تم ملفقة الأجهزة الحيوية ميكروفلويديك لدراسة الاستجابات الخلوية في التدفق قوة القص، 12 التدرجات الكيميائية و 13 و الكهربائية المحفزات 4 في المختبر. وقد خفضت تصنيع الأجهزة الحيوية ميكروفلويديك باستخدام polydimethylsiloxane (PDMS) أو البولى (PMMA، المعروف أيضا باسم الاكريليك) بنجاح على معدل فشل هذه التجارب. وعلاوة على ذلك، وذلك باستخدام أجهزة ميكروفلويديك القائمة على الاكريليك كنموذج للتحقيق في موضوعات البيولوجية هو أبسط من استخدام PDMS رقائق البطاطس. وقد وضعت العديد من الوظائف في الأجهزة القائمة على الاكريليك لانجذاب كهربي الدراسة. ومع ذلك، فإن أيا من التصاميم السابقة وتمكن من اختبار في وقت واحد آثار الظروف الكيميائية المختلفة و-الحقل الكهربائي في الخلايا للانجذاب كهربي الدراسة. وهكذا، قمنا بتطوير جهاز لميكروفلويديك موltichannel المزدوج الكهربائي الميدان (MDF) أربع قنوات ثقافة مستقلة وثمانية ظروف تجريبية مختلفة في رقاقة واحدة تحتوي على رقاقة. وMDF رقاقة القائمة على الاكريليك، لاول مرة من قبل هوى وآخرون، 8 يدمج التحفيز الكهربائي وعدة قنوات معزولة كيميائيا. هذه القنوات معزولة كيميائيا يمكن استخدامها لثقافة أنواع مختلفة من الخلايا في تجربة واحدة. يتم إنتاج dcEF في القنوات التي كتبها إمدادات الطاقة الكهربائية. حقلين الكهربائية المستقلة، واحدة مع التطبيقية القوة الكهربائية الميدان (EFS) وآخر مع 0 EFS، تجري في كل قناة معزولة كيميائيا. وبهذه الطريقة، يوفر رقاقة EF التعايش أفضل تسيطر عليها والتحفيز الكيميائي. وعلاوة على ذلك، نتائج المحاكاة العددية للنشر الكيميائية داخل الرقاقة MDF تشير إلى أن عدم وجود تلوث عبر وقعت بين القنوات بعد فترة تجريبية 24 ساعة. 8 مقارنة ديفيم ذكرت لي وآخرون، 14 رقاقة MDF يوفر مساحة الثقافة الأوسع، والذي يسمح لمزيد من التحليل الكيميائي للخلايا حفز كهربائيا. بالإضافة إلى ذلك، مع منطقة مراقبة أكبر شريحة MDF، والمزيد من الخلايا يمكن ملاحظة في الاختبار، وبالتالي فإن تحليل سرعة الهجرة أو توجيه الأعضاء من الخلايا حفز كهربائيا هو أكثر دقة. تصاميم رقاقة على قناة واحدة من الدراسات السابقة التي أبلغ عنها هوانغ وآخرون. (4) وتساي وآخرون 15 تسمح سوى نوع واحد من الخلايا او كيميائية لفحصها. ومع ذلك، فإن رقاقة MDF يمكن استخدامها لتحقيق آثار المواد الكيميائية المختلفة على انجذاب كهربي، فضلا عن آثار التحفيز الكهربائي على أنواع مختلفة من الخلايا. وبعبارة أخرى، فإن رقاقة MDF يسمح لدراسة كفاءة تبعيات الجرعة الكيميائية.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr >
			<td >Reagent</td>
			<td ></td>
			<td ></td>
			<td ></td>
		</tr>
		<tr >
			<td >DMEM medium</td>
			<td >Gibco,Invitrogen, USA</td>
			<td >12800-017</td>
			<td></td>
		</tr>
		<tr >
			<td >Fetal Bovine Serum</td>
			<td >Gibco,Invitrogen, USA</td>
			<td >16000-044</td>
			<td></td>
		</tr>
		<tr >
			<td >Trypsin</td>
			<td >Gibco,Invitrogen, USA</td>
			<td >25200-072</td>
			<td></td>
		</tr>
		<tr >
			<td >PBS</td>
			<td >Basic Life</td>
			<td >BL2651</td>
			<td></td>
		</tr>
		<tr >
			<td >Y-27632 (hydrochloride)</td>
			<td >Cayman Chemical Co</td>
			<td >10005583</td>
			<td></td>
		</tr>
		<tr >
			<td >agarose</td>
			<td >LONZO, USA</td>
			<td >SeaKem LE AGAROSE</td>
			<td></td>
		</tr>
		<tr >
			<td >syringe</td>
			<td>Terumo</td>
			<td>3 ml with Luer taper</td>
			<td></td>
		</tr>
		<tr >
			<td >3-way stopcock</td>
			<td>Nipro</td>
			<td >with Luer taper</td>
			<td></td>
		</tr>
		<tr >
			<td >PMMA (acrylic)</td>
			<td >HiShiRon Industries CO., Ltd, Taiwan</td>
			<td ></td>
			<td >thickness 1mm, 2mm</td>
		</tr>
		<tr >
			<td >acrylic adaptor</td>
			<td >KuanMin Technology Co., Ltd, Taichung, Taiwan</td>
			<td >1/4-28 port, 10x10x6 mm</td>
			<td>customized</td>
		</tr>
		<tr >
			<td >nut</td>
			<td >Thermo Fisher Scientific Inc.</td>
			<td >UPCHURCH:P-206x, P-200x, F120x, P-659, P-315x</td>
			<td></td>
		</tr>
		<tr >
			<td >Microscope cover glass</td>
			<td >Deckgl&#228;ser, Germany</td>
			<td >24x60 mm</td>
			<td></td>
		</tr>
		<tr >
			<td >double-sided tape</td>
			<td >3M</td>
			<td >PET 8018</td>
			<td></td>
		</tr>
		<tr >
			<td >super glue</td>
			<td >3M</td>
			<td >Scotch Liquid Plus Super Glue</td>
			<td></td>
		</tr>
		<tr >
			<td >Teflon tube</td>
			<td >HENG YI ENTERPRISE CO., LTD., Taiwan</td>
			<td >UPTB_06, DUPONT TEFLON BRAND RESIN FEP TUBING</td>
			<td>outer diameter 1/16 in., inner diameter 0.03 in.; Upchurch Scienti&#64257;c</td>
		</tr>
		<tr >
			<td >TFD4 detergent</td>
			<td >Franklab, France</td>
			<td >TFD4</td>
			<td></td>
		</tr>
		<tr >
			<td >ultrasonic steri cleaner</td>
			<td >LEO ULTRASONIC CO., LTD., Taiwan</td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >Thermo bonder</td>
			<td >KuanMin Technology Co., Ltd, Taichung, Taiwan</td>
			<td>customized</td>
			<td></td>
		</tr>
		<tr >
			<td >CO2 laser scriber</td>
			<td >LTT group, Taiwan</td>
			<td >ISL-II</td>
			<td></td>
		</tr>
		<tr >
			<td >indium tin oxide glass (ITO glass)</td>
			<td >AimCore Technology Co., Ltd</td>
			<td >TN/STN, &#8806;10&#937;</td>
			<td></td>
		</tr>
		<tr >
			<td >proportional-integral-derivative (PID) controller</td>
			<td>JETEC Electronics Co., Japen</td>
			<td >TTM-J40-R-AB,</td>
			<td></td>
		</tr>
		<tr >
			<td >K-type thermocouple</td>
			<td >TECPEL</td>
			<td >TPK-02A</td>
			<td></td>
		</tr>
		<tr >
			<td >4-channel syringe pump</td>
			<td >KdScientific, USA</td>
			<td >250P</td>
			<td></td>
		</tr>
		<tr >
			<td >DC power supply</td>
			<td >GWInstek, Taiwan</td>
			<td ></td>
			<td></td>
		</tr>
		<tr >
			<td >X-Y-Z motor stage</td>
			<td >TanLian, E-O Co. Ltd., Taiwan</td>
			<td>customized</td>
			<td></td>
		</tr>
		<tr >
			<td >inverted microscope</td>
			<td >Olympus, Japan</td>
			<td >CKX41</td>
			<td></td>
		</tr>
		<tr >
			<td >digital SLR camera</td>
			<td >Canon, Japan</td>
			<td >60D</td>
			<td></td>
		</tr>
	</tbody>
</table>

electrotaxis studies of lung cancer cells using a multichannel dual-electric-field microfluidic chip

يشار إلى سلوك الهجرة الخلية الاتجاه في ظل المباشر التيار الكهربائي الميدان (dcEF) على أنها انجذاب كهربي. وقد تجلى دور كبير الفسيولوجية dcEF في توجيه حركة الخلية أثناء تطور الجنين، تمايز الخلايا، والتئام الجروح في العديد من الدراسات. من خلال تطبيق رقائق ميكروفلويديك لمقايسة انجذاب كهربي، هو تقصير عملية التحقيق ويتم الحد من الأخطاء التجريبية. في السنوات الأخيرة، وأجهزة ميكروفلويديك المصنوعة من المواد البوليمرية (على سبيل المثال، البولى، PMMA، أو الاكريليك) أو (PDMS) polydimethylsiloxane استخدمت على نطاق واسع في دراسة ردود الخلايا لالتحفيز الكهربائي. ولكن، على عكس العديد من الخطوات اللازمة لصنع جهاز PDMS، وبناء بسيط وسريع للالصغرى الاكريليك فلوريدا رقاقة uidic يجعلها مناسبة لكلا النماذج الجهاز والإنتاج. إلا أن أيا من الأجهزة وذكرت تسهيل دراسة كفاءة المادة الكيميائية وهندسة المدنية في وقت واحدالآثار و على الخلايا. في هذا التقرير، وصفنا لدينا تصميم وتصنيع والمتعددة القائمة على الاكريليك المزدوج الكهربائي الميدان (MDF) رقاقة لدراسة تأثير المتزامنة الكيميائية والتحفيز الكهربائي على خلايا سرطان الرئة. يوفر رقاقة MDF ثماني مجموعات من التحفيز الكهربائية / الكيميائية في اختبار واحد. رقاقة ليس فقط يقصر كثيرا من الوقت تجريبي مطلوب ولكن أيضا يزيد من دقة في انجذاب كهربي الدراسات.

تصنيع وتجميع الجهاز MDF ويظهر رسم تخطيطي للMDF رقاقة الاكريليك ومقرها في الشكل 1A. استخدمت أربع صفائح الاكريليك والزجاج غطاء واحد، 13 محولات الاكريليك، وقطعة من الشريط ?...

Watch this Scientific Journal Video about Electrotaxis Studies of Lung Cancer Cells using a Multichannel Dual-electric-field Microfluidic Chip at JoVE.com

Electrotaxis Studies of Lung Cancer Cells using a Multichannel Dual-electric-field Microfluidic Chip

Many microfluidic devices have been developed for use in the study of electrotaxis. Yet, none of these chips allows the efficient study of the simultaneous chemical and electric-field (EF) effects on cells. We developed a polymethylmethacrylate-based device that offers better-controlled coexisting EF and chemical stimulation for use in electrotaxis research.

الدراسات انجذاب كهربي من الرئة خلايا سرطان باستخدام القنوات المتعددة ثنائي الكهربائية الميدان ميكروفلويديك رقاقة

The behavior of directional cell migration under a direct current electric-field (dcEF) is referred to as electrotaxis. The significant role of ...

electrotaxis-studies-lung-cancer-cells-using-multichannel-dual

Research

JoVE Journal

Bioengineering

8.6K Views.  Academia Sinica. Many microfluidic devices have been developed for use in the study of electrotaxis. Yet, none of these chips allows the efficient study of the simultaneous chemical and electric-field (EF) effects on cells. We developed a polymethylmethacrylate-based device that offers better-controlled coexisting EF and chemical stimulation for use in electrotaxis research.

Video: Electrotaxis Studies of Lung Cancer Cells using a Multichannel Dual-electric-field Microfluidic Chip

Fluorescence detection methods for microfluidic droplet platforms

The development of microfluidic platforms for performing chemistry and biology has in large part been driven by a range of potential benefits that accompany system miniaturisation. Advantages include the ability to efficiently process nano- to femoto- liter volumes of sample, facile integration of functional components, an intrinsic predisposition towards large-scale multiplexing, enhanced analytical throughput, improved control and reduced instrumental footprints.1
In recent years much interest has focussed on the development of droplet-based (or segmented flow) microfluidic systems and their potential as platforms in high-throughput experimentation.2-4 Here water-in-oil emulsions are made to spontaneously form in microfluidic channels as a result of capillary instabilities between the two immiscible phases. Importantly, microdroplets of precisely defined volumes and compositions can be generated at frequencies of several kHz. Furthermore, by encapsulating reagents of interest within isolated compartments separated by a continuous immiscible phase, both sample cross-talk and dispersion (diffusion- and Taylor-based) can be eliminated, which leads to minimal cross-contamination and the ability to time analytical processes with great accuracy. Additionally, since there is no contact between the contents of the droplets and the channel walls (which are wetted by the continuous phase) absorption and loss of reagents on the channel walls is prevented.
Once droplets of this kind have been generated and processed, it is necessary to extract the required analytical information. In this respect the detection method of choice should be rapid, provide high-sensitivity and low limits of detection, be applicable to a range of molecular species, be non-destructive and be able to be integrated with microfluidic devices in a facile manner. To address this need we have developed a suite of experimental tools and protocols that enable the extraction of large amounts of photophysical information from small-volume environments, and are applicable to the analysis of a wide range of physical, chemical and biological parameters. Herein two examples of these methods are presented and applied to the detection of single cells and the mapping of mixing processes inside picoliter-volume droplets. We report the entire experimental process including microfluidic chip fabrication, the optical setup and the process of droplet generation and detection.

Droplet-based microfluidic platforms are promising candidates for high throughput experimentation since they are able to generate picoliter, self-compartmentalized vessels inexpensively at kHz rates. Through integration with fast, sensitive and high resolution fluorescence spectroscopic methods, the large amounts of information generated within these systems can be efficiently extracted, harnessed and utilized.

طرق الكشف عن منصات مضان الحبرية ميكروفلويديك

The development of microfluidic platforms for performing chemistry and biology has in large part been driven by a range of potential benefits that ...

Microfluidic-based Electrotaxis for On-demand Quantitative Analysis of Caenorhabditis elegans' Locomotion

The nematode Caenorhabditis elegans is a versatile model organism for biomedical research because of its conservation of disease-related genes and pathways as well as its ease of cultivation. Several C. elegans disease models have been reported, including neurodegenerative disorders such as Parkinson's disease (PD), which involves the degeneration of dopaminergic (DA) neurons 1. Both transgenes and neurotoxic chemicals have been used to induce DA neurodegeneration and consequent movement defects in worms, allowing for investigations into the basis of neurodegeneration and screens for neuroprotective genes and compounds 2,3.
Screens in lower eukaryotes like C. elegans provide an efficient and economical means to identify compounds and genes affecting neuronal signaling. Conventional screens are typically performed manually and scored by visual inspection; consequently, they are time-consuming and prone to human errors. Additionally, most focus on cellular level analysis while ignoring locomotion, which is an especially important parameter for movement disorders.
We have developed a novel microfluidic screening system (Figure 1) that controls and quantifies C. elegans' locomotion using electric field stimuli inside microchannels. We have shown that a Direct Current (DC) field can robustly induce on-demand locomotion towards the cathode ("electrotaxis") 4. Reversing the field's polarity causes the worm to quickly reverse its direction as well. We have also shown that defects in dopaminergic and other sensory neurons alter the swimming response 5. Therefore, abnormalities in neuronal signaling can be determined using locomotion as a read-out. The movement response can be accurately quantified using a range of parameters such as swimming speed, body bending frequency and reversal time.
Our work has revealed that the electrotactic response varies with age. Specifically, young adults respond to a lower range of electric fields and move faster compared to larvae 4. These findings led us to design a new microfluidic device to passively sort worms by age and phenotype 6.
We have also tested the response of worms to pulsed DC and Alternating Current (AC) electric fields. Pulsed DC fields of various duty cycles effectively generated electrotaxis in both C. elegans and its cousin C. briggsae 7. In another experiment, symmetrical AC fields with frequencies ranging from 1 Hz to 3 KHz immobilized worms inside the channel 8.
Implementation of the electric field in a microfluidic environment enables rapid and automated execution of the electrotaxis assay. This approach promises to facilitate high-throughput genetic and chemical screens for factors affecting neuronal function and viability.

Microfluidic-based Electrotaxis for On-demand Quantitative Analysis of Caenorhabditis elegans&#039; Locomotion

A semi-automated micro-electro-fluidic method to induce on-demand locomotion in Caenorhabditis elegans is described. This method is based on the neurophysiologic phenomenon of worms responding to mild electric fields (&#x201C;electrotaxis&#x201D;) inside microfluidic channels. Microfluidic electrotaxis serves as a rapid, sensitive, low-cost, and scalable technique to screen for factors affecting neuronal health.

انجذاب كهربي المستندة ميكروفلويديك للتحليل الكمي بناء على الطلب<em&gt; انواع معينة ايليجانس</em&gt; &#39;تنقل

The nematode Caenorhabditis elegans is a versatile model organism for biomedical research because of its conservation of disease-related genes and ...

Microfluidic Chip Fabrication and Method to Detect Influenza

Fast and effective diagnostics play an important role in controlling infectious disease by enabling effective patient management and treatment. Here, we present an integrated microfluidic thermoplastic chip with the ability to amplify influenza A virus in patient nasopharyngeal (NP) swabs and aspirates. Upon loading the patient sample, the microfluidic device sequentially carries out on-chip cell lysis, RNA purification and concentration steps within the solid phase extraction (SPE), reverse transcription (RT) and polymerase chain reaction (PCR) in RT-PCR chambers, respectively. End-point detection is performed using an off-chip Bioanalyzer (Agilent Technologies, Santa Clara, CA). For peripherals, we used a single syringe pump to drive reagent and samples, while two thin film heaters were used as the heat sources for the RT and PCR chambers. The chip is designed to be single layer and suitable for high throughput manufacturing to reduce the fabrication time and cost. The microfluidic chip provides a platform to analyze a wide variety of virus and bacteria, limited only by changes in reagent design needed to detect new pathogens of interest.

An integrated microfluidic thermoplastic chip has been developed for use as a molecular diagnostic. The chip performs nucleic acid extraction, reverse transcriptase, and PCR. Methods for fabricating and running the chip are described.

ميكروفلويديك تصنيع المعالج وطريقة للكشف عن الأنفلونزا

Fast  and effective diagnostics play an important role in controlling infectious  disease by enabling effective patient management and treatment. Here, we ...

A Microfluidic Chip for the Versatile Chemical Analysis of Single Cells

We present a microfluidic device that enables the quantitative determination of intracellular biomolecules in multiple single cells in parallel. For this purpose, the cells are passively trapped in the middle of a microchamber. Upon activation of the control layer, the cell is isolated from the surrounding volume in a small chamber. The surrounding volume can then be exchanged without affecting the isolated cell. However, upon short opening and closing of the chamber, the solution in the chamber can be replaced within a few hundred milliseconds. Due to the reversibility of the chambers, the cells can be exposed to different solutions sequentially in a highly controllable fashion, e.g. for incubation, washing, and finally, cell lysis. The tightly sealed microchambers enable the retention of the lysate, minimize and control the dilution after cell lysis. Since lysis and analysis occur at the same location, high sensitivity is retained because no further dilution or loss of the analytes occurs during transport. The microchamber design therefore enables the reliable and reproducible analysis of very small copy numbers of intracellular molecules (attomoles, zeptomoles) released from individual cells. Furthermore, many microchambers can be arranged in an array format, allowing the analysis of many cells at once, given that suitable optical instruments are used for monitoring. We have already used the platform for proof-of-concept studies to analyze intracellular proteins, enzymes, cofactors and second messengers in either relative or absolute quantifiable manner.

In this article we present a microfluidic chip for single cell analysis. It allows the quantification of intracellular proteins, enzymes, cofactors, and second messengers by means of fluorescent assays or immunoassays.&#160;

رقاقة ميكروفلويديك للتحليل الكيميائي للخلايا متعددة الاستخدامات واحدة

We present a microfluidic device that enables the quantitative determination of intracellular biomolecules in multiple single cells in parallel. For this ...

A Microfluidic Chip for ICPMS Sample Introduction

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). The chip produces monodisperse aqueous sample droplets in perfluorohexane (PFH). Size and frequency of the aqueous droplets can be varied in the range of 40 to 60 &#181;m and from 90 to 7,000&#160;Hz, respectively. The droplets are ejected from the chip with a second flow of PFH and remain intact during the ejection. A custom-built desolvation system removes the PFH and transports the droplets into the ICPMS. Here, very stable signals with a narrow intensity distribution can be measured, showing the monodispersity of the droplets. We show that the introduction system can be used to quantitatively determine iron in single bovine red blood cells. In the future, the capabilities of the introduction device can easily be extended by the integration of additional microfluidic modules.

We present a discrete droplet sample introduction system for inductively coupled plasma mass spectrometry (ICPMS). It is based on a cheap and disposable microfluidic chip that generates highly monodisperse droplets in a size range of 40&#8722;60 &#181;m at frequencies from 90 to 7,000 Hz.

رقاقة ميكروفلويديك لICPMS مقدمة عينة

This protocol discusses the fabrication and usage of a disposable low cost microfluidic chip as sample introduction system for inductively coupled plasma ...

The Multi-organ Chip - A Microfluidic Platform for Long-term Multi-tissue Coculture

The ever growing amount of new substances released onto the market and the limited predictability of current in vitro test systems has led to a high need for new solutions for substance testing. Many drugs that have been removed from the market due to drug-induced liver injury released their toxic potential only after several doses of chronic testing in humans. However, a controlled microenvironment is pivotal for long-term multiple dosing experiments,&#160;as even minor alterations in extracellular conditions may greatly influence the cell physiology. We focused within our research program on the generation of a microengineered bioreactor, which can be dynamically perfused by an on-chip pump and combines at least two culture spaces for multi-organ applications. This circulatory system mimics the in vivo conditions of primary cell cultures better and assures a steadier,&#160;more quantifiable extracellular relay of signals to the cells. 
For demonstration purposes, human liver equivalents, generated by aggregating differentiated HepaRG cells with human hepatic stellate cells in hanging drop plates, were cocultured with human skin punch biopsies for up to 28 days inside the microbioreactor. The use of cell culture inserts enables the skin to be cultured at an air-liquid interface, allowing topical substance exposure. The microbioreactor system is capable of supporting these cocultures at near physiologic fluid flow and volume-to-liquid ratios, ensuring stable and organotypic culture conditions. The possibility of long-term cultures enables the repeated exposure to substances. Furthermore, a vascularization of the microfluidic channel circuit using human dermal microvascular endothelial cells yields a physiologically more relevant vascular model.

Here, we present a protocol to coculture primary cells, tissue models and punch biopsies in a microfluidic multi-organ chip for up to 28 days. Human dermal microvascular endothelial cells, liver aggregates and skin biopsies were successfully combined in a common media circulation.

رقاقة متعدد الجهاز - A منصة ميكروفلويديك لفترة طويلة Coculture متعدد الأنسجة

The ever growing amount of new substances released onto the market and the limited predictability of current in vitro test systems has led to a high need ...

Co-culture of Living Microbiome with Microengineered Human Intestinal Villi in a Gut-on-a-Chip Microfluidic Device

Here, we describe a protocol to perform long-term co-culture of multi-species human gut microbiome with microengineered intestinal villi in a human gut-on-a-chip microphysiological device. We recapitulate the intestinal lumen-capillary tissue interface in a microfluidic device, where physiological mechanical deformations and fluid shear flow are constantly applied to mimic peristalsis. In the lumen microchannel, human intestinal epithelial Caco-2 cells are cultured to form a &#39;germ-free&#39; villus epithelium and regenerate small intestinal villi. Pre-cultured microbial cells are inoculated into the lumen side to establish a host-microbe ecosystem. After microbial cells adhere to the apical surface of the villi, fluid flow and mechanical deformations are resumed to produce a steady-state microenvironment in which fresh culture medium is constantly supplied and unbound bacteria (as well as bacterial wastes) are continuously removed. After extended co-culture from days to weeks, multiple microcolonies are found to be randomly located between the villi, and both microbial and epithelial cells remain viable and functional for at least one week in culture. Our co-culture protocol can be adapted to provide a versatile platform for other host-microbiome ecosystems that can be found in various human organs, which may facilitate in vitro study of the role of human microbiome in orchestrating health and disease.

We describe an in vitro protocol to co-culture gut microbiome and intestinal villi for an extended period using a human gut-on-a-chip microphysiological system.

شارك في ثقافة المعيشة Microbiome مع المعوية الزوائد Microengineered الإنسان في الوتر على واحد في رقاقة ميكروفلويديك الأجهزة

Here, we describe a protocol to perform long-term co-culture of multi-species human gut microbiome with microengineered intestinal villi in a human ...

Dry Film Photoresist-based Electrochemical Microfluidic Biosensor Platform: Device Fabrication, On-chip Assay Preparation, and System Operation

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An easy-to-use and low-cost sensor platform is highly desired to measure various types of analytes (e.g., biomarkers, hormones, and drugs) quantitatively and specifically. For this reason, dry film photoresist technology - enabling cheap, facile, and high-throughput fabrication - was used to manufacture the microfluidic biosensor presented here. Depending on the bioassay used afterwards, the versatile platform is capable of detecting various types of biomolecules. For the fabrication of the device, platinum electrodes are structured on a flexible polyimide (PI) foil in the only clean-room process step. The PI foil serves as a substrate for the electrodes, which are insulated with an epoxy-based photoresist. The microfluidic channel is subsequently generated by the development and lamination of dry film photoresist (DFR) foils onto the PI wafer. By using a hydrophobic stopping barrier in the channel, the channel is separated into two specific areas: an immobilization section for the enzyme-linked assay and an electrochemical measurement cell for the amperometric signal readout.
The on-chip bioassay immobilization is performed by the adsorption of the biomolecules to the channel surface. The glucose oxidase enzyme is used as a transducer for electrochemical signal generation. In the presence of the substrate, glucose, hydrogen peroxide is produced, which is detected at the platinum working electrode. The stop-flow technique is applied to obtain signal amplification along with rapid detection. Different biomolecules can quantitatively be measured by means of the introduced microfluidic system, giving an indication of different types of diseases, or, in regard to therapeutic drug monitoring, facilitating a personalized therapy.

A microfluidic biosensor platform was designed and fabricated using low-cost dry film photoresist technology for the rapid and sensitive quantification of various analytes. This single-use system allows for the electrochemical readout of on-chip-immobilized enzyme-linked assays by means of the stop-flow technique.

الفيلم الجافة على أساس مقاوم الضوء Biosensor موائع جزيئية الكهروكيميائية منصة: تصنيع الجهاز وإعداد مقايسة على شريحة، ونظام التشغيل

In recent years, biomarker diagnostics became an indispensable tool for the diagnosis of human disease, especially for the point-of-care diagnostics. An ...

Immobilization of Live Caenorhabditis elegans Individuals Using an Ultra-thin Polydimethylsiloxane Microfluidic Chip with Water Retention

Radiation is widely used for biological applications and for ion-beam breeding, and among these methods, microbeam irradiation represents a powerful means of identifying radiosensitive sites in living organisms. This paper describes a series of on-chip immobilization methods developed for the targeted microbeam irradiation of live individuals of Caenorhabditis elegans. Notably, the treatment of the polydimethylsiloxane (PDMS) microfluidic chips that we previously developed to immobilize C. elegans individuals without the need for anesthesia is explained in detail. This chip, referred to as a worm sheet, is resilient to allow the microfluidic channels to be expanded, and the elasticity allows animals to be enveloped gently. Also, owing to the self-adsorption capacity of the PDMS, animals can be sealed in the channels by covering the surface of the worm sheet with a thin cover film, in which animals are not pushed into the channels for enclosure. By turning the cover film over, we can easily collect the animals. Furthermore, the worm sheet shows water retention and allows C. elegans individuals to be subjected to microscopic observation for long periods under live conditions. In addition, the sheet is only 300 &#181;m thick, allowing heavy ions such as carbon ions to pass through the sheet enclosing the animals, thus allowing the ion particles to be detected and the applied radiation dose to be measured accurately. Because selection of the cover films used for enclosing the animals is very important for successful long-term immobilization, we conducted the selection of the suitable cover films and showed a recommended one among some films. As an application example of the chip, we introduced imaging observation of muscular activities of animals enclosing the microfluidic channel of the worm sheet, as well as the microbeam irradiation. These examples indicate that the worm sheets have greatly expanded the possibilities for biological experiments.

Immobilization of Live Caenorhabditis elegans Individuals Using an Ultra-thin Polydimethylsiloxane Microfluidic Chip with Water Retention

A series of immobilization methods has been established to allow the targeted irradiation of live Caenorhabditis elegans individuals using a recently developed ultra-thin polydimethylsiloxane microfluidic chip with water retention. This novel on-chip immobilization is also adequate for imaging observations. The detailed treatment and application examples of the chip are explained.

التثبيت أفراد يعيش ايليجانس كاينورهابديتيس باستخدام رقاقة موائع جزيئية بولي دايمثيل سيلوكسان أولتراثين إلكترونية مع "الاحتفاظ بالماء"

Radiation is widely used for biological applications and for ion-beam breeding, and among these methods, microbeam irradiation represents a powerful means ...

Establishing Single-Cell Based Co-Cultures in a Deterministic Manner with a Microfluidic Chip

Cell co-culture assays have been widely used for studying cell-cell interactions between different cell types to better understand the biology of diseases including cancer. However, it is challenging to clarify the complex mechanism of intercellular interactions in highly heterogeneous cell populations using conventional co-culture systems because the heterogeneity of the cell subpopulation is obscured by the average values; the conventional co-culture systems can only be used to describe the population signal, but are incapable of tracking individual cells behavior. Furthermore, conventional single-cell experimental methods have low efficiency in cell manipulation because of the Poisson distribution. Microfabricated devices are an emerging technology for single-cell studies because they can accurately manipulate single cells at high-throughput and can reduce sample and reagent consumption. Here, we describe the concept and application of a microfluidic chip for multiple single-cell co-cultures. The chip can efficiently capture multiple types of single cells in a culture chamber (~46%) and has a sufficient culture space useful to study the cells&#39; behavior (e.g., migration, proliferation, etc.) under cell-cell interaction at the single-cell level. Lymphatic endothelial cells and oral squamous cell carcinoma were used to perform a single-cell co-culture experiment on the microfluidic platform for live multiple single-cell interaction studies.

This report describes a microfluidic chip-based method to set up a single cell culture experiment in which high-efficiency pairing and microscopic analysis of multiple single cells can be achieved.

إنشاء الثقافات المشتركة القائمة علي خليه واحده بطريقه قطعيه مع رقاقه ميكروفلويدريك

Cell co-culture assays have been widely used for studying cell-cell interactions between different cell types to better understand the biology of diseases ...