We would like to acknowledge the use of the clean room facility SMIF at Duke University. We also want to thank Hao Qiang for his assistance in measuring the jet velocity. The authors thank Todd Rumbaugh of Hadland Imaging for providing the Shimadzu HPV-X camera used in this study.The work was funded in part by NIH through grants 5R03EB017886-02 and 4R37DK052985-20.

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The authors have nothing to disclose.

ניתוח מתא בודד, בשילוב עם הדמיה לחיות תאים, שיפרה מאוד את הבנתנו של תהליכים דינמיים ולעיתים קרובות משתנה בתאים בודדים, כגון פיתוח פנוטיפ התגובה החיסונית 23. בניגוד תרבית התא הקונבנציונלי במנות או צלוחיות, מערכות microfluidic לאפשר שליטה מדויקת של microenvironment, עד לרמת התא...

יש הכרה גוברת כי ההטרוגניות הסלולר, הנובעים ביטוי סטוכסטיים של גנים, חלבונים, מטבוליטים, קיימת בתוך אוכלוסיית תאים גדולה ומשמשות כעיקרון יסוד בביולוגיה כדי לאפשר הסתגלות תא אבולוצית 1. לכן, הוא לעתים קרובות לא מדויק ולא אמין להשתמש מדידות בתפזורת מבוססת אוכלוסייה להבין את תפקידם של תאים בודדים ואת האינטראקציות ביניהם. פיתוח טכנולוגיות חדשות לניתוח-תא בודד ולכן הוא בעל עניין רב במחקר ביולוגי תרופתי, והוא יכול לשמש, למשל, להבין את מסלולי איתות מפתח טוב יותר תהליכים בביולוגיה תא גזע וסרטן טיפול 2-4. בשנים האחרונות, את הופעתה של פלטפורמות microfluidic יש להקל מאוד ניתוח תא בודד, שבו המיצוב, טיפול, והתצפית על תגובת תאים בודדים בוצעו עם אסטרטגיות האנליטי חדישות 5. Cavitation ממלא תפקיד חשוב במגוון רחב של יישומים ביו, כולל לטיפול בסרטן על ידי-ממוקד בעוצמה גבוהה אולטרסאונד (HIFU) 6, הפיצול לא פולשנית של אבנים בכליות על ידי lithotripsy גל הלם (SWL) 7, משלוח סמים או גנים על ידי sonoporation 8, והרס דיווחה לאחרונה של תאים או רקמות ידי 9,10 cavitation בועה הידרודינמית. למרות זאת, התהליכים הדינמיים של בועת cavitation (ים) אינטראקציות עם רקמות ביולוגיות ותאים לא הובנו היטב. זאת בשל אקראית בדינמיקת ייזום בועת cavitation המיוצרת על ידי אולטרסאונד, גלי הלם, ואת לחץ הידראולי מקומי; יתר על כן, קיים חוסר המאפשר טכניקות לפתרון תגובות מורכבות ומהירות מיסודו של תאים ביולוגיים, במיוחד ברמת התא הבודד. בגלל האתגרים הללו, אין זה מפתיע כי מחקרים מעטים יש דבורהn דיווח לחקור אינטראקציות תאי בועה בתנאים ניסיוניים מבוקרים היטב. לדוגמא, poration הממברנה של תאים בודדים לכודי השעית 11 ואת העיוות הגדולה אימפולסיבית של תאי דם אדומים אדם 12 הודגמה באמצעות בועות יחידות שנוצר ליזר בערוצי microfluidic. הטכניקה השנייה, לעומת זאת, יכולה לייצר רק עיוות קטנה מאוד בתאים איקריוטיים בגלל הנוכחות של הגרעין 13. יתר על כן, קשה לפקח bioeffects במורד הזרם כאשר מטפלים התאים בתרחיף. במחקרים אחרים, עירור אולטרסאונד של microbubble כלוא (או חומר ניגוד אולטרסאונד) להפקת poration קרום ו / או תשובות סידן תאי בתאי חסיד יחידים דווח 8. Poration ממברנה של תאים חסידים יחידים יכול גם להיות מיוצר באמצעות בועות טנדם שנוצר ליזר בשכבת נוזל דקה המכיל פתרון הכחול Trypan קליטת אור 14, אועל ידי בועת גז נדנוד שנוצרה על ידי פעימות ליזר המיקרו irradiating דרך מצע סופג אופטי ב microchambers 15. כשמשווה, המצע הקליט האופטי יש יתרון על פני הפתרון הכחול הליזר סופג Trypan משום שהאחרון הוא רעיל לתאים. יתרה מכך, בועות שנוצרו ליזר יותר לשליטה מבחינת גודל בועה ומיקום מ בועות נרגשות מבחינה אקוסטית. אף על פי כן, בכל המחקרים הקודמים הללו, תא הצורה, הנטייה, ותנאי ההידבקות לא נשלטו, אשר עשויים להשפיע באופן משמעותי את תגובת תא bioeffects המיוצר על ידי מכני מדגיש 16. כדי להתגבר על חסרונות אלה במחקרים קודמים, פתחנו לאחרונה מערכת ניסיונית עבור דור בועה, דפוסי תא, אינטראקציות בועת בועת תאים, ו- bioassays בזמן אמת של תגובת תא שבב microfluidic נבנה באמצעות שילוב ייחודי של techn microfabricationiques. שלושה מאפיינים עיקריים להבחין המערכת הניסיונית שלנו מאחרים בתחום הם: 1) הדפוסים של נקודות זהב בגודל מיקרון על מצע הזכוכית כדי לאפשר קליטת ליזר מקומית לייצור בועה 17; 2) דפוסים של איים בגודל מיקרון של תאי מטריקס (ECM) עבור הידבקות התא על פני המצע אותו לשלוט הן את המיקום ואת הגיאומטריה של תאים בודדים; ו -3) דחיסה של הממד של תחום האינטראקציה בועות תאים בועה מ 3D למרחב מעין-2D כדי להקל ב-המטוס להדמיה של אינטראקציות בועה בועה, jetting שדות זרימה, עיוות התא, bioeffects, כל שנתפסו אחד רצף הדמיה יעיל (איור 1D). <img alt="איור 1" src="/files/ftp_upload/55106/55106fig1.jpg" /> איור 1: השבב ו שרטוטי microfluidic של מבחנים שונים. א) שבב microfluidic התאסף עם ערוצים מלא דיו כחול<html> לשם ויזואליזציה. ב) באזור בתוך השבב microfluidic עם תאים בדוגמת נקודות זהב (המרחק בין שתי נקודות זהב בסמיכות הוא 40 מיקרומטר). זוגות רבים של יחידות עבודה ניתן לארגן בתוך ערוץ. ג) תמונה מקרוב של יחידת עבודה, מורכב של זוג נקודות זהב ו תא הלה דבק באזור תא-הדפוסים. ד) סכמטי של פעולת המכשיר. תא בודד דבק ומתפשט על האי &quot;H&quot; -shaped מצופה פיברונקטין. זוג בועות cavitation (בועת טנדם) עם תנודה אנטי שלב מיוצר על-ידי הארת קרן ליזר פעמה על נקודות הזהב (ראה תרשים 4 א), שמובילה את הדור של מטוס מהיר מקומי נע לכיוון תא המטרה סמוך. התא עלול להיות מעווה, porated לספיגת macromolecular, ו / או מגורה עם תגובת סידן, בהתאם למרחק התיקו (ד S) של התא לבועה טנדם.f = &quot;http://ecsource.jove.com/files/ftp_upload/55106/55106fig1large.jpg&quot; target = &quot;_ blank&quot;&gt; לחץ כאן כדי לצפות בגרסה גדולה יותר של דמות זו. פלטפורמה זו ניתן לשלב נוסף עם מבחני קרינה וחרוזים פונקציונליים המחוברים אל פני השטח של תא bioeffects נגרמת cavitation. בפרט, פלטפורמה זו סוללת את הדרך עבור מבחני אמין וכמותיים ברמת התא הבודד. עד עכשיו, יש לנו השתמשתי במכשיר לניתוח דפורמציה קרום תא הנגרמת בועת טנדם, poration תא ספיג תאי, כדאיות, אפופטוזיס, ותגובת סידן תוך תאים. בפרוטוקול הבא, אנו מתארים את תהליך ייצור שבבי ההליך לניתוח bioeffects השונה המוזכר לעיל. יתר על כן, הפעילות של השבב גם מתוארת.

<table border="0" cellpadding="0" cellspacing="0" width="678">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Reagent/Materials</td>
			<td style="width:171px;"></td>
			<td style="width:155px;"></td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">75x38mm Plain Microscope Slides</td>
			<td style="width:171px;">Corning</td>
			<td style="width:155px;">2947-75X38</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Acetone</td>
			<td style="width:171px;">Sigma Aldrich, Co.</td>
			<td style="width:155px;">320110</td>
			<td style="width:179px;">ACS reagent, &#8805;99.5%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Isopropyl alcohol</td>
			<td style="width:171px;">Sigma Aldrich, Co.</td>
			<td style="width:155px;">W292907</td>
			<td style="width:179px;">&#8805;99.7%, FCC, FG</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Sulfuric acid</td>
			<td style="width:171px;">Sigma Aldrich, Co.</td>
			<td style="width:155px;">320501</td>
			<td style="width:179px;">ACS reagent, 95.0-98.0%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Hydrogen peroxide</td>
			<td style="width:171px;">Sigma Aldrich, Co.</td>
			<td style="width:155px;">216763</td>
			<td style="width:179px;">30 wt.% in H2O</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Primer P-20</td>
			<td style="width:171px;">Microchem</td>
			<td style="width:155px;">MCC Primer 80/20</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">NFR photoresist</td>
			<td style="width:171px;">JSR</td>
			<td style="width:155px;">NFR016D2</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Photomask</td>
			<td style="width:171px;">Photoplotstore</td>
			<td style="width:155px;">N/A</td>
			<td style="width:179px;">4x4 Direct write mask</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">MF-319 Developer</td>
			<td style="width:171px;">Shipley (Rohm and Haas)</td>
			<td style="width:155px;">Microposit MF-319</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">1165 Photoresist Remover</td>
			<td style="width:171px;">Dow Chemical, Co.</td>
			<td style="width:155px;">DEM-10018073</td>
			<td style="width:179px;">1-methyl-2-pyrrolidinone based</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">S1813 photoresist</td>
			<td style="width:171px;">Shipley (Rohm and Haas)</td>
			<td style="width:155px;">S1813</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">PLL-g-PEG</td>
			<td style="width:171px;">SuSoS</td>
			<td style="width:155px;">PLL(20)-g[3.5]- PEG(2)</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">HEPES</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">15630080</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Paraffin film</td>
			<td style="width:171px;">HACH</td>
			<td style="width:155px;">251764</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">SU-2025 photoresist</td>
			<td style="width:171px;">Microchem</td>
			<td style="width:155px;">SU-2025</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">PDMS</td>
			<td style="width:171px;">Dow Corning</td>
			<td style="width:155px;">184 SIL ELAST KIT 0.5KG</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Microbore Tubing</td>
			<td style="width:171px;">Saint-Gobain PPL Corp.</td>
			<td style="width:155px;">S-54-HL</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:175px;">Metal pins</td>
			<td style="width:171px;">New England Small Tube</td>
			<td style="width:155px;">NE-1300-01</td>
			<td style="width:179px;">&#160;Cut Tube (straight), 0.025&#8221; OD x 0.017&#8221; ID x 0.50&#8221; Long</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">HeLa cells</td>
			<td style="width:171px;">Duke Cell Culture Facility</td>
			<td style="width:155px;">(307-CCL-2) HeLa, p.148</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">DPBS(1X) buffer</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">14190144</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">DMEM culture medium</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">11995065</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Fibronectin Bovine Protein, Plasma</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">33010018</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">0.25% Trypsin-EDTA (1X)</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">25200056</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Propidium Iodide</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">P21493</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Carboxylate Microspheres 1.00&#956;m</td>
			<td style="width:171px;">Polysciences, Inc</td>
			<td style="width:155px;">08226-15</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Carboxylate Microspheres 2.00&#956;m</td>
			<td style="width:171px;">Polysciences, Inc</td>
			<td style="width:155px;">18327-10</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:175px;">EDC (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride)</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">22980</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:175px;">Sulfo-NHS</td>
			<td style="width:171px;">Sulfo-NHS (N-hydroxysulfosuccinimide)</td>
			<td style="width:155px;">24510</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Peptite-2000</td>
			<td style="width:171px;">Advanced BioMatrix</td>
			<td style="width:155px;">5020-5MG</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">FITC Annexin V</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">A13199</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Fura-2, AM</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">F1221</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">DMSO</td>
			<td style="width:171px;">Sigma Aldrich, Co.</td>
			<td style="width:155px;">D2650</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">F-127</td>
			<td style="width:171px;">invitrogen</td>
			<td style="width:155px;">P6866</td>
			<td style="width:179px;">0.2 &#181;m filtered (10% Solution in Water)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Reduced serum media&#160;</td>
			<td style="width:171px;">ThermoFisher Scientific</td>
			<td style="width:155px;">11058021</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Name</td>
			<td style="width:171px;">Company</td>
			<td style="width:155px;">Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:175px;">Plasma asher</td>
			<td style="width:171px;">Emitech</td>
			<td style="width:155px;">K-1050X</td>
			<td style="width:179px;">O2 / Ar plasma ashing of photoresist and other organic materials</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Mask aligner</td>
			<td style="width:171px;">SUSS MicroTec&#160;</td>
			<td style="width:155px;">Karl Suss MA6/BA6</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">E-beam evaporator</td>
			<td style="width:171px;">CHA Industries</td>
			<td style="width:155px;">CHA Industries Solution E-Beam</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">RIE</td>
			<td style="width:171px;">Trion Technology&#160;</td>
			<td style="width:155px;">Trion Technology Phantom II</td>
			<td style="width:179px;">(oxide/ nitride/ polymer) etching</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Stereoscope</td>
			<td style="width:171px;">AmScope</td>
			<td style="width:155px;">American Scope SM-4TZ-FRL</td>
			<td style="width:179px;">Stereo Microscope</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Syringe pump</td>
			<td style="width:171px;">Chemyx Inc</td>
			<td style="width:155px;">NanoJet</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="67">
			<td height="67" style="height:67px;width:175px;">Cell culture incubator</td>
			<td style="width:171px;">NuAire</td>
			<td style="width:155px;">AutoFlow NU-8500 Water Jacket CO2 Incubator</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Biological Safety Cabinets</td>
			<td style="width:171px;">NuAire</td>
			<td style="width:155px;">NU-425-400</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Water bath</td>
			<td style="width:171px;">VWR</td>
			<td style="width:155px;">1122s</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Centrifuge</td>
			<td style="width:171px;">IEC</td>
			<td style="width:155px;">Centra CL2</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Microscope</td>
			<td style="width:171px;">Zeiss</td>
			<td style="width:155px;">Axio Observer Z1</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Nd:YAG laser&#160; (laser 1)</td>
			<td style="width:171px;">New Wave Research</td>
			<td style="width:155px;">Tempest</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Nd:YAG laser&#160; (laser 2)</td>
			<td style="width:171px;">New Wave Research</td>
			<td style="width:155px;">Orion</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">Delay generator</td>
			<td style="width:171px;">Berkeley Nucleonics&#160;</td>
			<td style="width:155px;">BNC 565-8c</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:175px;">Flash lamp</td>
			<td style="width:171px;">Dyna-Lite</td>
			<td style="width:155px;">ML1000 fiber-coupled flashtube</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">high speed camera</td>
			<td style="width:171px;">DRS Hadland</td>
			<td style="width:155px;">&#160;Imacon 200</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">high speed&#160; camera</td>
			<td style="width:171px;">Shimadzu</td>
			<td style="width:155px;">HPV-X</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">high speed camera</td>
			<td style="width:171px;">Vision Research</td>
			<td style="width:155px;">Phantom V7.3</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">PIV software</td>
			<td style="width:171px;">LaVision</td>
			<td style="width:155px;">DaVis 7.2</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">camera</td>
			<td style="width:171px;">Zeiss</td>
			<td style="width:155px;">AxioCam MRc 5</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">software</td>
			<td style="width:171px;">Zeiss</td>
			<td style="width:155px;">AxioVision</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">PTI system</td>
			<td style="width:171px;">Horiba</td>
			<td style="width:155px;">S/N: 1705 RAM-X</td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">EasyRatio software</td>
			<td style="width:171px;">Horiba</td>
			<td style="width:155px;">Easy Ratio Pro 2</td>
			<td style="width:179px;">version 2.3.125.86</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:175px;">63&#215; objective</td>
			<td style="width:171px;">Zeiss</td>
			<td style="width:155px;">LD Plan Neofluar</td>
			<td style="width:179px;"></td>
		</tr>
	</tbody>
</table>

a microfluidic system with surface patterning for investigating cavitation bubble(s)&#8211;cell interaction and the resultant bioeffects at the single-cell level

בכתב היד הזה, אנחנו ראשונים מתארים את פרוטוקול הייצור של שבב microfluidic, עם נקודות זהב ואזורים מצופים פיברונקטין על מצע הזכוכית אותו, כי בדיוק שולט הדור של בועות טנדם תאים בודדים בדוגמת סמוכה עם במקומות מוגדרים היטב צורות. לאחר מכן, אנו מדגימים את הדור של בועות טנדם באמצעות שני לייזרים פעמו ומאיר זוג נקודות זהב עם שהייה כמה המיקרו. אנו לדמיין את אינטראקצית בועת הבועה והיווצרות סילון ידי הדמיה מהירה ולאפיין את שדה הזרימה כתוצאה באמצעות velocimetry תמונת חלקיקים (PIV). לבסוף, אנו מציגים כמה יישומים של הטכניקה הזו לניתוח תא בודד, כולל poration קרום תא עם ספיגת מקרומולקולה, דפורמציה קרום המקומי שקבעה ההתקות של חרוזי integrin המחייב מצורפים, ותגובת סידן תאיים הדמית ratiometric. התוצאות שלנו מראות כי תזרים טיסות הללו מהיר כיוונית הוא פרוduced ידי אינטראקצית בועת טנדם, אשר יכול להטיל מאמץ גזירה מקומית מאוד על פני השטח של תאים גדלים בסמיכות. יתר על כן, יכול להיגרם bioeffects שונים על ידי שינוי עוצמת הזרם הטיסות הללו על ידי התאמת המרחק תיקו מהתא אל בועות טנדם.

<html> פלטפורמת microfluidic המתוארת בעבודה זו יכולה לשמש כדי לחקור אינטראקציות בועת בועה וכדי לנתח מגוון של bioeffects נגרמת cavitation ברמת התא הבודד. כאן, אנו מציגים מספר דוגמאות להפגין מגוון של מחקרים ניסויים ו- bioassays שניתן לבצע במערכת הניסוי שלנו. נדגים את האינטרא...

Watch this Scientific Journal Video about A Microfluidic System with Surface Patterning for Investigating Cavitation Bubblesâ€“Cell Interaction and the Resultant Bioeffects at the Single-cell Lev

A Microfluidic System with Surface Patterning for Investigating Cavitation Bubble(s)&#8211;Cell Interaction and the Resultant Bioeffects at the Single-cell Level

A microfluidic chip was fabricated to produce pairs of gold dots for tandem bubble generation and fibronectin-coated islands for single-cell patterning nearby. The resultant flow field was characterized by particle image velocimetry and was employed to study various bioeffects, including cell membrane poration, membrane deformation, and intracellular calcium response.

מערכת Microfluidic עם דפוסי Surface לחקירת בועת Cavitation (ים) אינטראקציה דו תא ואת Bioeffects הנובע מהן ברמת התא הבודד

In this manuscript, we first describe the fabrication protocol of a microfluidic chip, with gold dots and fibronectin-coated regions on the same glass ...

a-microfluidic-system-with-surface-patterning-for-investigating

Universidad de Cartagena UDEC

Research

JoVE Journal

Bioengineering

11.7K Views.  Duke University. A microfluidic chip was fabricated to produce pairs of gold dots for tandem bubble generation and fibronectin-coated islands for single-cell patterning nearby. The resultant flow field was characterized by particle image velocimetry and was employed to study various bioeffects, including cell membrane poration, membrane deformation, and intracellular calcium response.

Video: A Microfluidic System with Surface Patterning for Investigating Cavitation Bubble(s)–Cell Interaction and the Resultant Bioeffects at the Single-cell Level

Plasma Lithography Surface Patterning for Creation of Cell Networks

Systematic manipulation of a cell microenvironment with micro- and nanoscale resolution is often required for deciphering various cellular and molecular phenomena. To address this requirement, we have developed a plasma lithography technique to manipulate the cellular microenvironment by creating a patterned surface with feature sizes ranging from 100 nm to millimeters. The goal of this technique is to be able to study, in a controlled way, the behaviors of individual cells as well as groups of cells and their interactions.
This plasma lithography method is based on selective modification of the surface chemistry on a substrate by means of shielding the contact of low-temperature plasma with a physical mold. This selective shielding leaves a chemical pattern which can guide cell attachment and movement. This pattern, or surface template, can then be used to create networks of cells whose structure can mimic that found in nature and produces a controllable environment for experimental investigations. The technique is well suited to studying biological phenomenon as it produces stable surface patterns on transparent polymeric substrates in a biocompatible manner. The surface patterns last for weeks to months and can thus guide interaction with cells for long time periods which facilitates the study of long-term cellular processes, such as differentiation and adaption. The modification to the surface is primarily chemical in nature and thus does not introduce topographical or physical interference for interpretation of results. It also does not involve any harsh or toxic substances to achieve patterning and is compatible for tissue culture. Furthermore, it can be applied to modify various types of polymeric substrates, which due to the ability to tune their properties are ideal for and are widely used in biological applications. The resolution achievable is also beneficial, as isolation of specific processes such as migration, adhesion, or binding allows for discrete, clear observations at the single to multicell level.
This method has been employed to form diverse networks of different cell types for investigations involving migration, signaling, tissue formation, and the behavior and interactions of neurons arraigned in a network.

A versatile plasma lithography technique has been developed to generate stable surface patterns for guiding cellular attachment. This technique can be applied to create cell networks including those that mimic natural tissues and has been used for studying several, distinct cell types.

Surface פלזמה ליתוגרפיה דפוסים של יצירת רשתות Cell

Systematic manipulation of a cell microenvironment with micro- and nanoscale resolution is often required for deciphering various cellular and molecular ...

Gold Nanostar Synthesis with a Silver Seed Mediated Growth Method

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest in using nano-colloids for photo-thermal ablation, drug delivery and many other biomedical applications 6. Gold is particularly used because of its low toxicity 7-9. A property of metal nano-colloids is that they can have a strong surface plasmon resonance 10. The peak of the surface plasmon resonance mode depends on the structure and composition of the metal nano-colloids. Since the surface plasmon resonance mode is stimulated with light there is a need to have the peak absorbance in the near infrared where biological tissue transmissivity is maximal 11, 12.
We present a method to synthesize star shaped colloidal gold, also known as star shaped nanoparticles 13-15 or nanostars 16. This method is based on a solution containing silver seeds that are used as the nucleating agent for anisotropic growth of gold colloids 17-22. Scanning electron microscopy (SEM) analysis of the resulting gold colloid showed that 70 % of the nanostructures were nanostars. The other 30 % of the particles were amorphous clusters of decahedra and rhomboids. The absorbance peak of the nanostars was detected to be in the near infrared (840 nm). Thus, our method produces gold nanostars suitable for biomedical applications, particularly for photo-thermal ablation.

We synthesized star shaped gold nanostars using a silver seed mediated growth method. The diameter of the nanostars ranges from 200 to 300 nm and the number of tips vary from 7 to 10. The nanoparticles have a broad surface plasmon resonance mode centered in the near infrared.

זהב Nanostar סינתזה עם שיטת Seed כסף מתווכת צמיחה

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest ...

Microfluidic Picoliter Bioreactor for Microbial Single-cell Analysis: Fabrication, System Setup, and Operation

In this protocol the fabrication, experimental setup and basic operation of the recently introduced microfluidic picoliter bioreactor (PLBR) is described in detail. The PLBR can be utilized for the analysis of single bacteria and microcolonies to investigate biotechnological and microbiological related questions concerning, e.g.&#160;cell growth, morphology, stress response, and metabolite or protein production on single-cell level. The device features continuous media flow enabling constant environmental conditions for perturbation studies, but in addition allows fast medium changes as well as oscillating conditions to mimic any desired environmental situation. To fabricate the single use devices, a silicon wafer containing sub micrometer sized SU-8 structures served as the replication mold for rapid polydimethylsiloxane casting. Chips were cut, assembled, connected, and set up onto a high resolution and fully automated microscope suited for time-lapse imaging, a powerful tool for spatio-temporal cell analysis. Here, the biotechnological platform organism Corynebacterium glutamicum&#160;was seeded into the PLBR and cell growth and intracellular fluorescence were followed over several hours unraveling time dependent population heterogeneity on single-cell level, not possible with conventional analysis methods such as flow cytometry. Besides insights into device fabrication, furthermore, the preparation of the preculture, loading, trapping of bacteria, and the PLBR cultivation of single cells and colonies is demonstrated. These devices will add a new dimension in microbiological research to analyze time dependent phenomena of single bacteria under tight environmental control. Due to the simple and relatively short fabrication process the technology can be easily adapted at any microfluidics lab and simply tailored towards specific needs.

In this protocol the fabrication, setup and basic operation of a microfluidic picoliter bioreactor (PLBR) for single-cell analysis of prokaryotic microorganisms is introduced. Industrially relevant microorganisms were analyzed as proof of principle allowing insights into growth rate, morphology, and phenotypic heterogeneity over certain time periods, hardly possible with conventional methods.

In this protocol the fabrication, experimental setup and basic operation of the recently introduced microfluidic picoliter bioreactor (PLBR) is described ...

Quantitative and Temporal Control of Oxygen Microenvironment at the Single Islet Level

Simultaneous oxygenation and monitoring of glucose stimulus-secretion coupling factors in a single technique is critical for modeling pathophysiological states of islet hypoxia, especially in transplant environments. Standard hypoxic chamber techniques cannot modulate both stimulations at the same time nor provide real-time monitoring of glucose stimulus-secretion coupling factors. To address these difficulties, we applied a multilayered microfluidic technique to integrate both aqueous and gas phase modulations via a diffusion membrane. This creates a stimulation sandwich around the microscaled islets within the transparent polydimethylsiloxane (PDMS) device, enabling monitoring of the aforementioned coupling factors via fluorescence microscopy. Additionally, the gas input is controlled by a pair of microdispensers, providing quantitative, sub-minute modulations of oxygen between 0-21%. This intermittent hypoxia is applied to investigate a new phenomenon of islet preconditioning. Moreover, armed with multimodal microscopy, we were able to look at detailed calcium and KATP channel dynamics during these hypoxic events. We envision microfluidic hypoxia, especially this simultaneous dual phase technique, as a valuable tool in studying islets as well as many ex vivo tissues.

Microfluidic oxygen control confers more than just convenience and speed over hypoxic chambers for biological experiments. Especially when implemented via diffusion through a membrane, microfluidic oxygen can provide simultaneous liquid and gas phase modulations at the microscale-level. This technique enables dynamic multi-parametric experiments critical for studying islet pathophysiology.

בקרה כמותי וזמנית של Microenvironment חמצן ברמה יחיד Islet

Simultaneous oxygenation and monitoring of glucose stimulus-secretion coupling factors in a single technique is critical for modeling pathophysiological ...

Cell Patterning on Photolithographically Defined 
Parylene-C: SiO2 Substrates

Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain central aspects of cellular physiology. To easily combine cell patterning with Multi-Electrode Arrays (MEAs) and silicon-based &#8216;lab on a chip&#8217; technologies, a microfabrication-compatible protocol is required. We describe a method that utilizes deposition of the polymer parylene-C on SiO2&#160;wafers. Photolithography enables accurate and reliable patterning of parylene-C at micron-level resolution. Subsequent activation by immersion in fetal bovine serum (or another specific activation solution) results in a substrate in which cultured cells adhere to, or are repulsed by, parylene or SiO2 regions respectively. This technique has allowed patterning of a broad range of cell types (including primary murine hippocampal cells, HEK 293 cell line, human neuron-like teratocarcinoma cell line, primary murine cerebellar granule cells, and primary human glioma-derived stem-like cells). Interestingly, however, the platform is not universal; reflecting the importance of cell-specific adhesion molecules. This cell patterning process is cost effective, reliable, and importantly can be incorporated into standard microfabrication (chip manufacturing) protocols, paving the way for integration of microelectronic technology.

Cell Patterning on Photolithographically Defined 
Parylene-C: SiO2 Substrates

This protocol describes a microfabrication-compatible method for cell patterning on SiO2. A predefined parylene-C design is photolithographically printed on SiO2 wafers. Following incubation with serum (or other activation solution) cells adhere specifically to (and grow according to the conformity of) underlying parylene-C, whilst being repulsed by SiO2 regions.

תא דפוסים על photolithographically מוגדר Parylene-C: SiO<sub&gt; 2</sub&gt; מצעים

Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain ...

Investigating Receptor-ligand Systems of the Cellulosome with AFM-based Single-molecule Force Spectroscopy

Cellulosomes are discrete multienzyme complexes used by a subset of anaerobic bacteria and fungi to digest lignocellulosic substrates. Assembly of the enzymes onto the noncatalytic scaffold protein is directed by interactions among a family of related receptor-ligand pairs comprising interacting cohesin and dockerin modules. The extremely strong binding between cohesin and dockerin modules results in dissociation constants in the low picomolar to nanomolar range, which may hamper accurate off-rate measurements with conventional bulk methods. Single-molecule force spectroscopy (SMFS) with the atomic force microscope measures the response of individual biomolecules to force, and in contrast to other single-molecule manipulation methods (i.e.&#160;optical tweezers), is optimal for studying high-affinity receptor-ligand interactions because of its ability to probe the high-force regime (&#62;120 pN). Here we present our complete protocol for studying cellulosomal protein assemblies at the single-molecule level. Using a protein topology derived from the native cellulosome, we worked with enzyme-dockerin and carbohydrate binding module-cohesin (CBM-cohesin) fusion proteins, each with an accessible free thiol group at an engineered cysteine residue. We present our site-specific surface immobilization protocol, along with our measurement and data analysis procedure for obtaining detailed binding parameters for the high-affinity complex. We demonstrate how to quantify single subdomain unfolding forces, complex rupture forces, kinetic off-rates, and potential widths of the binding well. The successful application of these methods in characterizing the cohesin-dockerin interaction responsible for assembly of multidomain cellulolytic complexes is further described.

Cellulosomes are multienzyme complexes designed for digesting cellulose. AFM-based SMFS was used to study the mechanical properties and folding configuration of cellulosome-associated protein assemblies. We present a complete workflow for protein immobilization, data acquisition, and data analysis to study the interactions of individual receptor-ligand complexes involved in cellulosome assembly.

חוקר מערכות קולטן ליגנד של Cellulosome עם המולקולה בודדת מבוססת AFM חיל ספקטרוסקופיה

Cellulosomes are discrete multienzyme complexes used by a subset of anaerobic bacteria and fungi to digest lignocellulosic substrates. Assembly of the ...

Microfluidic Fabrication of Polymeric and Biohybrid Fibers with Predesigned Size and Shape

A &#8220;sheath&#8221; fluid passing through a microfluidic channel at low Reynolds number can be directed around another &#8220;core&#8221; stream and used to dictate the shape as well as the diameter of a core stream.&#160;Grooves in the top and bottom of a microfluidic channel were designed to direct the sheath fluid and shape the core fluid.&#160;By matching the viscosity and hydrophilicity of the sheath and core fluids, the interfacial effects are minimized and complex fluid shapes can be formed.&#160;Controlling the relative flow rates of the sheath and core fluids determines the cross-sectional area of the core fluid.&#160;Fibers have been produced with sizes ranging from 300 nm to ~1 mm, and fiber cross-sections can be round, flat, square, or complex as in the case with double anchor fibers. Polymerization of the core fluid downstream from the shaping region solidifies the fibers.&#160;Photoinitiated click chemistries are well suited for rapid polymerization of the core fluid by irradiation with ultraviolet light.&#160;Fibers with a wide variety of shapes have been produced from a list of polymers including liquid crystals, poly(methylmethacrylate), thiol-ene and thiol-yne resins, polyethylene glycol, and hydrogel derivatives. Minimal shear during the shaping process and mild polymerization conditions also makes the fabrication process well suited for encapsulation of cells and other biological components.

Two adjacent fluids passing through a grooved microfluidic channel can be directed to form a sheath around a prepolymer core; thereby&#160;determining both shape and cross-section. Photoinitiated polymerization, such as thiol click chemistry, is well suited for rapidly solidifying the core fluid into a microfiber with predetermined size and shape.

ייצור מיקרופלואידי של סיבים פולימריים וביוהיברידים עם גודל וצורה מעוצבים מראש

A &#8220;sheath&#8221; fluid passing through a microfluidic channel at low Reynolds number can be directed around another &#8220;core&#8221; stream and ...

A Novel Method for Localizing Reporter Fluorescent Beads Near the Cell Culture Surface for Traction Force Microscopy

PA gels have long been used as a platform to study cell traction forces due to ease of fabrication and the ability to tune their elastic properties. When the substrate is coated with an extracellular matrix protein, cells adhere to the gel and apply forces, causing the gel to deform. The deformation depends on the cell traction and the elastic properties of the gel. If the deformation field of the surface is known, surface traction can be calculated using elasticity theory. Gel deformation is commonly measured by embedding fluorescent marker beads uniformly into the gel. The probes displace as the gel deforms. The probes near the surface of the gel are tracked. The displacements reported by these probes are considered as surface displacements. Their depths from the surface are ignored. This assumption introduces error in traction force evaluations. For precise measurement of cell forces, it is critical for the location of the beads to be known. We have developed a technique that utilizes simple chemistry to confine fluorescent marker beads, 0.1 and 1 &#181;m in diameter, in PA gels, within 1.6 &#956;m of the surface. We coat a coverslip with poly-D-lysine (PDL) and fluorescent beads. PA gel solution is then sandwiched between the coverslip and an adherent surface. The fluorescent beads transfer to the gel solution during curing. After polymerization, the PA gel contains fluorescent beads on a plane close to the gel surface.

Traditional techniques for fabricating polyacrylamide (PA) gels containing fluorescent probes involve sandwiching a gel between an adherent surface and a glass slide. Here, we show that coating this slide with poly-D-lysine (PDL) and fluorescent probes localizes the probes to within 1.6 &#181;m from the gel surface.

שיטה חדשה ללוקליזציה חרוזי ניאון כתב סמוך לפני שטח תרבית תאים לגרירה מיקרוסקופית כוח

PA gels have long been used as a platform to study cell traction forces due to ease of fabrication and the ability to tune their elastic properties. When ...

A Microfluidic Platform for High-throughput Single-cell Isolation and Culture

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet high-throughput, method to perform single-cell culture experiments. Here, we report a microfluidic chip-based strategy for high-efficiency single-cell isolation (~77%) and demonstrate its capability of performing long-term single-cell culture (up to 7 d) and cellular heterogeneity analysis using clonogenic assay. These applications were demonstrated with KT98 mouse neural stem cells, and A549 and MDA-MB-435 human cancer cells. High single-cell isolation efficiency and long-term culture capability are achieved by using different sizes of microwells on the top and bottom of the microfluidic channel. The small microwell array is designed for precisely isolating single-cells, and the large microwell array is used for single-cell clonal culture in the microfluidic chip. This microfluidic platform constitutes an attractive approach for single-cell culture applications, due to its flexibility of adjustable cell culture spaces for different culture strategies, without decreasing isolation efficiency.

Here, we present a protocol for isolating and culturing single cells with a microfluidic platform, which utilizes a new microwell design concept to allow for high-efficiency single cell isolation and long-term clonal culture.

פלטפורמת Microfluidic עבור בידוד תפוקה גבוהה מתא בודד ותרבות

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet ...

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.

עמית תרבות Microbiome חי עם Microengineered אדם המעיים villi בתוך גוט-על-שבב מכשיר microfluidic

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