החוקרים מכירים במענק הלאומית לבריאות והמועצה למחקר הרפואי של אוסטרליה (NHMRC # 1000674) לLJR פוסטר.

1. הכנת פתרון SurgiLux <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> הכן את פתרון 2% (v / v) של חומצה אצטית באמצעות מי deionized בכוס זכוכית נקיה; להשתמש ברדס זרימה למינרית כדי למנוע זיהום. </li><li style=";text-align:right;direction:rtl"> שוקל 0.02% (w / v) של chromophore, indocyanine ירוק, ICG, בצינור אפנדורף סטרילית, ולהבטיח את הצינור עטוף בנייר כסף כדי למנוע חדירת אור. </li><li style=";text-align:right;direction:rtl"> באמצעות פיפטה נקיה, חד פעמית, להעביר כ 1 מ&quot;ל של תמיסת החומצה אצטית המדוללת לצינור להמסת הצבע, ללחוץ בעדינות ולשמור עטופים בנייר כסף. </li><li style=";text-align:right;direction:rtl"> העברת ICG solubilized לתוך הכוס ולהוסיף 2% (w / v) של אבקת chitosan לפני הוספת stirrer מגנטי סטרילי. </li><li style=";text-align:right;direction:rtl"> לכסות את הכוס בParafilm אז לעטוף בנייר כסף, לפני שערבבתי את התוכן בכ 125 סל&quot;ד במשך 72 שעות בטמפרטורת חדר ובברדס זרימה למינרית. </li><li style=";text-align:right;direction:rtl"> מעביר את התוכן לתוך צינורות צנטריפוגות נקיים וצנטריפוגות ב15000 XG במשך 15 דקות ב 4 ° C כדי להסיר כל particulaעניין טה. </li><li style=";text-align:right;direction:rtl"> בזהירות להעביר את פתרון SurgiLux הירוק לתוך כוס זכוכית נקיה, לכסות באמצעות Parafilm אז לעטוף בנייר כסף, לפני האחסון במקרר למשך 12 שעות כדי להגדיל את הצמיגות של הפתרון. </li></ol> 2. ליהוק של SurgiLux סרטים <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> שימוש במזרק סטרילי, לוותר על 8 מ&quot;ל של פתרון SurgiLux הקר לתוך צלחת נקיה, פטרי בקוטר מ&quot;מ 95, ובעדינות להטות את הצלחת כדי להבטיח כיסוי מלא של הפתרון. משנה את היחס בין נפח פתרון לאזור יציקה מאפשרת שליטה בעובי הסרט, ראה איור 1. </li><li style=";text-align:right;direction:rtl"> הסר את כל בועות גלויות בפתרון באמצעות קצה מחט סטרילית. מכסה את התבנית בנייר כסף ומניחים במקרר כדי להסיר כל בועות שיורית בגודל מיקרון. </li><li style=";text-align:right;direction:rtl"> לאחר 20 דקות להסיר בזהירות את צלחת פטרי מהמקרר, מקום במכסת מנוע זרימה למינרית, מכסה בנייר כסף ולהשאיר את הפתרון להתאדות למשך 3 שבועות. </li><li style=";text-align:right;direction:rtl"> לאחר שיתוףאידוי mplete, ניקוד הקצוות החיצוניים של סרט SurgiLux הירוק והצלול בצלחת הפטר ובעדינות &quot;לקלף&quot; את הסרט ממשטח הצלחת. </li><li style=";text-align:right;direction:rtl"> סרט SurgiLux צריך להיות גמיש ומניפולציות בקלות מבלי לקרוע או לשבור. </li><li style=";text-align:right;direction:rtl"> אחסן את סרטי SurgiLux המעגליים בצלחת פטרי עטופים בנייר כסף בתנאים יבשים עד לשימוש. </li></ol> 3. הפעלת ליזר של סרטי SurgiLux הדבקים <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> כדי להדגים את תהליך הפעלת הליזר נשתמש פיסת רקמת בקר כגון סטייק לחתוך לגודל של 15 מ&quot;מ רחב ואורך 20 מ&quot;מ. מנתח את הרקמה בקו ישר באמצעות סכין כירורגית מספר 10, כדי לייצר 2 חתיכות של 15 על ידי 10 מ&quot;מימ. </li><li style=";text-align:right;direction:rtl"> מקורב לשתי החתיכות של רקמות, כך שקצותיהם נוגעים אך לא חופפים, ובאמצעות קיסם אוזניים או גזה, בעדינות לקלוט את כל נוזלים עודפים. </li><li style=";text-align:right;direction:rtl"> בשלב בא, לחתוך חתיכת סרט SurgiLux 7 x 9 מ&quot;מ ואורכו למקם את הסרט בזהירות על פני עמ &#39;החצויiece של רקמה, ולאחר מכן לחץ כלפי מטה בעדינות עם צמר גפן יבש. </li><li style=";text-align:right;direction:rtl"> סרטי SurgiLux מופעלים באמצעות דיודת ליזר אינפרא אדום בהגדרה של 120 mW. היות שמדובר בליזר IIIB כיתה, אמצעי בטיחות המתאימה יש לנקוט, ובכלל זה השימוש במשקפי בטיחות המתאימים לכל האדם. </li><li style=";text-align:right;direction:rtl"> החל בפינה, תקרין SurgiLux עם ליזר אינפרא אדום נקבע על 120 mW וגודל נקודת קרן בקוטר 1 מ&quot;מ. להעביר את מקום אלומת האור על הסרט הירוק בשיעור של כ 1 מ&quot;מ לשנייה. חזור על תהליך ההקרנה פעמים נוספות. </li></ol> 4. כוחו של התיקון <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> זהירות להבטיח את הקצוות של הרקמה במהדק של כלי בדיקת מתיחה. אנחנו משתמשים במערכת Mini55 Instron עם תא 50 ניוטון עומס. העומס המרבי, חוזק מתיחה, והסיומת בהפסקה חושבו באמצעות תוכנת מחשב Bluehill (ארה&quot;ב). אמצעים מלפחות 10 דגימות נקבעו (n = 10). </li><li style=";text-align:right;direction:rtl"> קח את &#39;הרפוי&#39;ולאחר מכן להפריד את חלקי רקמות בשיעור של 1 מ&quot;מ לשנייה, עד ששתי פיסות רקמה שהוחזקו יחד ברצועה הנפרדת לחלוטין SurgiLux. </li></ol>

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	<li>Kjaergard, H. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suture+support:+is+it+advantageous.">Suture support: is it advantageous.</a> Am. J. Surg. 182, 15S-20S (2001).</li><li>Lauto, A., Mawad, D., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adhesive+biomaterials+for+tissue+reconstruction.">Adhesive biomaterials for tissue reconstruction.</a> J. Chem. Tech. Biotech. 83, 464-472 (2008).</li><li>Fung, L. C., Mingin, G. C., Massicotte, M., Felsen, D., Poppas, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+temperature+on+tissue+thermal+injury+and+wound+strength+after+photochemical+wound+closure.">Effects of temperature on tissue thermal injury and wound strength after photochemical wound closure.</a> Lasers Surg. Med. 25, 285-290 (1999).</li><li>Piribo, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Glues &amp; Sealants: Industry Background Report. , (2005).</li><li>Lauto, A., Hook, J., Doran, M., Camacho, F., Poole-Warren, L. A., Avolio, A., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chitosan+adhesive+for+laser+tissue-welding:+in+vitro+characterisation.">Chitosan adhesive for laser tissue-welding: in vitro characterisation.</a> Lasers Surg. Med. 36, 193-201 (2005).</li><li>Lauto, A., Stoodley, M., Marcel, H., Avolio, A., Sarris, M., McKenzie, G., Sampson, D. D., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+and+in+vivo+tissue+repair+with+laser-activated+chitosan+adhesive.">In vitro and in vivo tissue repair with laser-activated chitosan adhesive.</a> Lasers Surg. Med. 39, 19-27 (2007).</li><li>Lauto, A., Foster, L. J. R., Avolio, A., Sampson, D., Raston, C., Sarris, M., McKenzie, G., Stoodley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sutureless+Nerve+Repair+with+Laser-Activated+Chitosan+Adhesive:+A+Pilot+in+vivo+Study.">Sutureless Nerve Repair with Laser-Activated Chitosan Adhesive: A Pilot in vivo Study.</a> J. Photomed. Laser. Surg. 26 (3), 227-234 (2008).</li><li>Mar&#231;al, H., Badylak, S. F., Sellaro, T. L., Lauto, A., Foster, L. J. R., Mahler, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+coalescence+of+decellularized+tissue+scaffolds,+laser-activated+chitosan+bioadhesive+and+olfactory+ensheathing+cells+for+tissue+repair+and+regeneration+of+the+spinal+cord.">The coalescence of decellularized tissue scaffolds, laser-activated chitosan bioadhesive and olfactory ensheathing cells for tissue repair and regeneration of the spinal cord.</a> Lasers Med. Sci. 23 (1), 96 (2008).</li><li>Foster, L. J. R., Thomson, K., Marcal, H., Butt, J., Watson, S., Wakefield, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+chitosan-vancomycin+composite+biomaterial+as+a+laser+activated+surgical+adhesive+with+regional+antimicrobial+activity.">A chitosan-vancomycin composite biomaterial as a laser activated surgical adhesive with regional antimicrobial activity.</a> Biomacromolecules. 11 (12), 3563-3570 (2010).</li><li>Shahbazi, J., Marcal, H., Watson, S., Wakefield, D., Sarris, M., Foster, L. J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sutureless+sealing+of+penetrating+corneal+wounds+using+a+laser-activated+thin+film+adhesive.">Sutureless sealing of penetrating corneal wounds using a laser-activated thin film adhesive.</a> Lasers Surg. Med. , .</li><li>Meyers, M. A., Chen, P. -. Y., Lin, A. Y. -. M., Seki, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+materials:+Structure+and+mechanical+properties.">Biological materials: Structure and mechanical properties.</a> Prog. Mater. Sci. 53 (1), 1-206 (2008).</li></ol>

אין ניגודי האינטרסים הכריזו.

Chitosan ניתן להשיג במגוון משקלים מולקולריים ועם דרגות שונות של deactylation (DDA). וריאציות על טוהר chitosan עלולות להוביל לנוכחות של חלקיקים בפתרון SurgiLux; צנטריפוגה משמשת לחסל אלה ואמורים לגרום פתרון ירוק שקוף. עם זאת, סינון יכול לשמש גם כצעד ייצור נוסף או חלופי. כמו בכל עיבוד חומרי?...

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> שם המגיב / הציוד </td><td> חברה </td><td> מספר קטלוגים </td><td> תגובות (אופציונלי) </td></tr><tr><td> Chitosan </td><td> סיגמה אולדריץ </td><td> 448877 </td><td></td></tr><tr><td> Indocyanine ירוק </td><td> סיגמה אולדריץ </td><td> I2633 </td><td> ידוע גם בשם Cardiogreen </td></tr><tr><td> חומצה אצטית </td><td> סיגמה אולדריץ </td><td> 320099 </td><td></td></tr><tr><td> דיודת ליזר אינפרא אדום עם אספקת סיבים. (808 ננומטר, 120 mW, 200 מיקרומטר ליבת Beam) </td><td> CNI לייזרים </td><td> Fc-808 </td><td> מערכת משתנית עד 5 ואט חשמל </td></tr><tr><td> ליזר משקפי בטיחות </td><td> CNI לייזרים </td><td> LS-G </td><td></td></tr><tr><td> מנגנון בדיקת מתיחה </td><td> Instron Pty Ltd </td><td> 5542 </td><td> תא 50 N עומס </td></tr></tbody></table>

a chitosan based, laser activated thin film surgical adhesive, 'surgilux': preparation and demonstration

תפרים הם טכנולוגיה ישנה 4000 שנה שתישאר &quot;זהב הסטנדרטי&quot; לסגירת פצע מכוח כוח תיקונם (~ 100 kPa ב). עם זאת, תפרים יכולים לפעול כnidus לזיהום ובנהלים רבים אינם מסוגלים לחולל תיקון פצע או להפריע לשיקום רקמות פונקציונליים. 1 דבקי כירורגים ודבקים, כגון אלה המבוססים על פיברין וcyanoacrylates, פותחו כתחליף לתפרים ל התיקון של פצעים כאלה. עם זאת, דבקים מסחריים נוכחיים יש גם חסרונות משמעותיים, החל מהעברת נגיפים ופריונים וחוסר כוח התיקון כמו עם דבקי הפיברין, לרעילות רקמה וחוסר biocompatibility לדבקים המבוססים cyanoacrylate. יתר על כן, דבקים כירורגיים זמינים כרגע נוטים להיות מבוסס ג&#39;ל ויכולים הרחיבו זמני ריפוי המגבילים את יישומם. 2 באופן דומה, השימוש בלייזרי UV כדי להקל על מנגנוני צלב מקשר-ב &#39;סול המבוסס על חלבון או אלבומיןders &#39;יכול להוביל לניזק לדנ&quot;א בזמן ריתוך רקמות ליזר (LTW) לתשומת ניזק תרמי לרקמות. 3 למרות החסרונות, הדבקים וLTW כבשו כ 30% משוק סגירת הפצע דיווחו להיות בעודף של 5 מליארד דולרים ארה&quot;ב לשנה, עדות משמעותית לצורך בטכנולוגית sutureless. 4 במרדף האחר טכנולוגית sutureless יש לנו מנוצלים chitosan כחומר ביולוגי לפיתוח סרט גמיש, דק, דבק ניתוחי ליזר הופעל מכונה &#39;SurgiLux&#39;. bioadhesive רומן זה משתמש בשילוב ייחודי של חומרים ביולוגיים ופוטוניקה שאשרו ה-FDA ושמש בהצלחה במגוון רחב של יישומים ומוצרים ביו. SurgiLux מתגבר על כל החסרונות הקשורים לתפרים ודבקים כירורגיים שוטפים (ראה טבלה 1). במצגת זו אנו מדווחים פרוטוקול פשוט יחסית עבור הייצור של SurgiLux ולהפגיןהפעלתה הליזר וכוח ריתוך רקמות. סרטי SurgiLux לדבוק רקמת collagenous ללא שינוי כימי כגון צלב קישור ודרך הקרנה באמצעות (120 MW) ליזר אינפרא אדום נמוך יחסית מונע במקום אור UV. סרטי Chitosan יש משיכת דבק טבעית, אבל חלשה לקולגן (~ 3 kPa ב), הפעלת ליזר של chitosan המבוססים SurgiLux הסרטים מדגישה את כוחה של הידבקות זה דרך אינטראקציות שרשרת פולימר כתוצאה מהתפשטות תרמית חולפת. 5 ללא תהליך זה &#39;הפעלה&#39; , סרטי SurgiLux יוסרו בקלות. 6-9 SurgiLux נבדק במבחנת in vivo על מגוון רקמות כוללים עצב, מעי, מאטר וקרנית דורה. בכל המקרים שהוכיח biocompatibility טוב וניזק תרמי זניח כתוצאה מקרינה. 6-10

צנטריפוגה מובילה לפתרון שקוף ירוק, דבר המגדיל את הצמיגות לאחר אחסון ב4-6 ° C. לאחר שעמד במשך 3 שבועות, פתרון הירוק הופך לסרט SurgiLux ירוק שקוף מיקרון כ 20 עבה ו, כפי שמודגם בוידאו, הוא בקלות גמישה. לאחר ההקרנה עם הליזר, את קשרי סרט SurgiLux לרק?...

Watch this Scientific Journal Video about A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration at JoVE.com

A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, &#039;SurgiLux&#039;: Preparation and Demonstration

הייצור של רומן, הדבק גמיש סרט דק כירורגית ממרכיבי ה-FDA אשרו, chitosan וירוק indocyanine מתואר. מליטה של ​​דבק זה לרקמת collagenous באמצעות תהליך הפעלה פשוט עם ליזר נמוך מופעל אינפרא אדום הפגינה.

Chitosan מבוסס, דבק הליזר הופעל סרט דק כירורגים, &#39;SurgiLux&#39;: הכנה והפגנה

Sutures are a 4,000 year old technology that remain the 'gold-standard' for wound closure by virtue of their repair strength (~100 KPa). However, sutures ...

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A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration

13.1K Views.  University of New South Wales. הייצור של רומן, הדבק גמיש סרט דק כירורגית ממרכיבי ה-FDA אשרו, chitosan וירוק indocyanine מתואר. מליטה של ​​דבק זה לרקמת collagenous באמצעות תהליך הפעלה פשוט עם ליזר נמוך מופעל אינפרא אדום הפגינה.

Video: A Chitosan Based, Laser Activated Thin Film Surgical Adhesive, 'SurgiLux': Preparation and Demonstration

Constructing a Collagen Hydrogel for the Delivery of Stem Cell-loaded Chitosan Microspheres

Multipotent stem cells have been shown to be extremely useful in the field of regenerative medicine1-3. However, in order to use these cells effectively for tissue regeneration, a number of variables must be taken into account. These variables include: the total volume and surface area of the implantation site, the mechanical properties of the tissue and the tissue microenvironment, which includes the amount of vascularization and the components of the extracellular matrix. Therefore, the materials being used to deliver these cells must be biocompatible with a defined chemical composition while maintaining a mechanical strength that mimics the host tissue. These materials must also be permeable to oxygen and nutrients to provide a favorable microenvironment for cells to attach and proliferate. Chitosan, a cationic polysaccharide with excellent biocompatibility, can be easily chemically modified and has a high affinity to bind with in vivo macromolecules4-5. Chitosan mimics the glycosaminoglycan portion of the extracellular matrix, enabling it to function as a substrate for cell adhesion, migration and proliferation. In this study we utilize chitosan in the form of microspheres to deliver adipose-derived stem cells (ASC) into a collagen based three-dimensional scaffold6. An ideal cell-to-microsphere ratio was determined with respect to incubation time and cell density to achieve maximum number of cells that could be loaded. Once ASC are seeded onto the chitosan microspheres (CSM), they are embedded in a collagen scaffold and can be maintained in culture for extended periods. In summary, this study provides a method to precisely deliver stem cells within a three dimensional biomaterial scaffold.

A major hurdle in current stem cell therapies is determining the most effective method to deliver these cells to host tissues. Here, we describe a chitosan-based delivery method that is efficient and simple in approach, while allowing adipose-derived stem cells to maintain their multipotency.

בניית Hydrogel קולגן עבור משלוח של התא טעון גזע Chitosan microspheres

Multipotent stem cells have been shown to be extremely useful in the field of regenerative medicine1-3. However, in order to use these cells effectively ...

Fabrication and Application of Rose Bengal-chitosan Films in Laser Tissue Repair

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two tissue edges1,2. These are then irradiated by a laser that is selectively absorbed by the RB. The resulting photochemical reactions supposedly crosslink the collagen fibers in the tissue with minimal heat production3. In this report, RB has been incorporated in thin chitosan films to fabricate a novel tissue adhesive that is laser-activated. Adhesive films, based on chitosan and containing ~0.1 wt% RB, are fabricated and bonded to calf intestine and rat tibial nerves by a solid state laser (&lambda;=532 nm, Fluence~110 J/cm2, spot size~0.5 cm). A single-column tensiometer, interfaced with a personal computer, is used to test the bonding strength. The RB-chitosan adhesive bonds firmly to the intestine with a strength of 15 &plusmn; 6 kPa, (n=30). The adhesion strength drops to 2 &plusmn; 2 kPa (n=30) when the laser is not applied to the adhesive. The anastomosis of tibial nerves can be also completed without the use of sutures. A novel chitosan adhesive has been fabricated that bonds photochemically to tissue and does not require sutures.

Sutures are usually needed to repair tissue during surgical procedures. However, their application can be problematic as they are invasive and may damage tissue. The fabrication and application methods of a novel tissue adhesive are here reported. This adhesive film is laser-activated and does not require the use of sutures.

ייצור ויישום של רוז בנגל-chitosan סרטים בתיקון רקמות ליזר

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two ...

Creating Adhesive and Soluble Gradients for Imaging Cell Migration with Fluorescence Microscopy

Cells can sense and migrate towards higher concentrations of adhesive cues such as the glycoproteins of the extracellular matrix and soluble cues such as growth factors. Here, we outline a method to create opposing gradients of adhesive and soluble cues in a microfluidic chamber, which is compatible with live cell imaging. A copolymer of poly-L-lysine and polyethylene glycol (PLL-PEG) is employed to passivate glass coverslips and prevent non-specific adsorption of biomolecules and cells. Next, microcontact printing or dip pen lithography are used to create tracks of streptavidin on the passivated surfaces to serve as anchoring points for the biotinylated peptide arginine-glycine-aspartic acid (RGD) as the adhesive cue. A microfluidic device is placed onto the modified surface and used to create the gradient of adhesive cues (100% RGD to 0% RGD) on the streptavidin tracks. Finally, the same microfluidic device is used to create a gradient of a chemoattractant such as fetal bovine serum (FBS), as the soluble cue in the opposite direction of the gradient of adhesive cues.

A method for the assembly of adhesive and soluble gradients in a microscopy chamber for live cell migration studies is described. The engineered environment combines antifouling surfaces and adhesive tracks with solution gradients and therefore allows one to determine the relative importance of guidance cues.

יצירת Gradients הדבק והמסיס לנדידת תאי דימות באמצעות מיקרוסקופ פלואורסצנטי

Cells can sense and migrate towards higher concentrations of adhesive cues such as the glycoproteins of the extracellular matrix and soluble cues such as ...

Insertion of Flexible Neural Probes Using Rigid Stiffeners Attached with Biodissolvable Adhesive

Microelectrode arrays for neural interface devices that are made of biocompatible thin-film polymer are expected to have extended functional lifetime because the flexible material may minimize adverse tissue response caused by micromotion. However, their flexibility prevents them from being accurately inserted into neural tissue. This article demonstrates a method to temporarily attach a flexible microelectrode probe to a rigid stiffener using biodissolvable polyethylene glycol (PEG) to facilitate precise, surgical insertion of the probe. A unique stiffener design allows for uniform distribution of the PEG adhesive along the length of the probe. Flip-chip bonding, a common tool used in microelectronics packaging, enables accurate and repeatable alignment and attachment of the probe to the stiffener. The probe and stiffener are surgically implanted together, then the PEG is allowed to dissolve so that the stiffener can be extracted leaving the probe in place. Finally, an in vitro test method is used to evaluate stiffener extraction in an agarose gel model of brain tissue. This approach to implantation has proven particularly advantageous for longer flexible probes (&gt;3 mm). It also provides a feasible method to implant dual-sided flexible probes. To date, the technique has been used to obtain various in vivo recording data from the rat cortex.

Insertion of flexible neural microelectrode probes is enabled by attaching probes to rigid stiffeners with polyethylene glycol (PEG). A unique assembly process ensures uniform and repeatable attachment. After insertion into tissue, the PEG dissolves and the stiffener is extracted. An in vitro test method evaluates the technique in agarose gel.

החדרת גמישה עצביות בדיקות באמצעות אלמנטים קשיחות קשיחים מצורפים עם Biodissolvable דבק

Microelectrode  arrays for neural interface devices that are made of biocompatible thin-film  polymer are expected to have extended functional lifetime ...

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or erosion. Amelogenin has been proven to be a critical protein for controlling the organized growth of apatite crystals. In this paper, we present a detailed protocol for superficial enamel reconstruction by using a novel amelogenin-chitosan hydrogel. Compared to other conventional treatments, such as topical fluoride and mouthwash, this method not only has the potential to prevent the development of dental caries but also promotes significant and durable enamel restoration. The organized enamel-like microstructure regulated by amelogenin assemblies can significantly improve the mechanical properties of etched enamel, while the dense enamel-restoration interface formed by an in situ regrowth of apatite crystals can improve the effectiveness and durability of restorations. Furthermore, chitosan hydrogel is easy to use and can suppress bacterial infection, which is the major risk factor for the occurrence of dental caries. Therefore, this biocompatible and biodegradable amelogenin-chitosan hydrogel shows promise as a biomaterial for the prevention, restoration, and treatment of defective enamel.

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

In this article, we describe a protocol for fabricating an amelogenin-chitosan hydrogel for superficial enamel reconstruction. Organized in situ growth of apatite crystals in the hydrogel formed a dense enamel-restoration interface, which will improve the effectiveness and durability of restorations.

פיתוח של Hydrogel Amelogenin-chitosan עבור<em&gt; במבחנה</em&gt; אמייל לצמיחה מחודשת עם ממשק צפוף

Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or ...

Custom-designed Laser-based Heating Apparatus for Triggered Release of Cisplatin from Thermosensitive Liposomes with Magnetic Resonance Image Guidance

Liposomes have been employed as drug delivery systems to target solid tumors through exploitation of the enhanced permeability and retention (EPR) effect resulting in significant reductions in systemic toxicity. Nonetheless, insufficient release of encapsulated drug from liposomes has limited their clinical efficacy. Temperature-sensitive liposomes have been engineered to provide site-specific release of drug in order to overcome the problem of limited tumor drug bioavailability. Our lab has designed and developed a heat-activated thermosensitive liposome formulation of cisplatin (CDDP), known as HTLC, to provide triggered release of CDDP at solid tumors. Heat-activated delivery in vivo was achieved in murine models using a custom-built laser-based heating apparatus that provides a conformal heating pattern at the tumor site as confirmed by MR thermometry (MRT). A fiber optic temperature monitoring device was used to measure the temperature in real-time during the entire heating period with online adjustment of heat delivery by alternating the laser power. Drug delivery was optimized under magnetic resonance (MR) image guidance by co-encapsulation of an MR contrast agent (i.e.,&#160;gadoteridol) along with CDDP into the thermosensitive liposomes as a means to validate the heating protocol and to assess tumor accumulation. The heating protocol consisted of a preheating period of 5 min prior to administration of HTLC and 20 min heating post-injection. This heating protocol resulted in effective release of the encapsulated agents with the highest MR signal change observed in the heated tumor in comparison to the unheated tumor and muscle. This study demonstrated the successful application of the laser-based heating apparatus for preclinical thermosensitive liposome development and the importance of MR-guided validation of the heating protocol for optimization of drug delivery.

AN MRI-compatible&#160;custom-designed laser-based heating apparatus has been developed to provide local heating of subcutaneous tumors in order to activate release of agents from thermosensitive liposomes specifically at the tumor region.

מכשירי חימום המבוסס על לייזר מותאם אישית המיועדים לשחרור עורר, ציספלטין מThermosensitive יפוזומים עם הדרכת תמונת תהודה מגנטית

Liposomes have been employed as drug delivery systems to target solid tumors through exploitation of the enhanced permeability and retention (EPR) effect ...

Automated Lipid Bilayer Membrane Formation Using a Polydimethylsiloxane Thin Film

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for biosensor applications. However, conventional BLM formation techniques have several drawbacks and they often require specific expertise and laborious processes. In particular, conventional BLMs suffer from low formation success rates and inconsistent membrane formation time. Here, we demonstrate a storable and transportable BLM formation system with controlled thinning-out time and enhanced BLM formation rate by replacing conventionally used films (polytetrafluoroethylene, polyoxymethylene, polystyrene) to polydimethylsiloxane (PDMS). In this experiment, a porous-structured polymer such as PDMS thin film is used. In addition, as opposed to conventionally used solvents with low viscosity, the use of squalene permitted a controlled thinning-out time via slow solvent absorption by PDMS, prolonging membrane lifetime. In addition, by using a mixture of squalene and hexadecane, the freezing point of the lipid solution was increased (~16 &#176;C), in addition, membrane precursors were produced that can be indefinitely stored and readily transported. These membrane precursors have reduced BLM formation time of &#60; 1 hr and achieved a BLM formation rate of ~80%. Moreover, ion channel experiments with gramicidin A demonstrated the feasibility of the membrane system.

We demonstrate a storable, transportable lipid bilayer formation system. A lipid bilayer membrane can be formed within 1 hr with over 80% success rate when a frozen membrane precursor is brought to ambient temperature. This system will reduce laborious processes and expertise associated with ion channels.

גיבוש ליפידים אוטומטי bilayer ממברנה באמצעות סרט polydimethylsiloxane רזה

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for ...

Image-guided, Laser-based Fabrication of Vascular-derived Microfluidic Networks

This detailed protocol outlines the implementation of image-guided, laser-based hydrogel degradation for the fabrication of vascular-derived microfluidic networks embedded in PEGDA hydrogels. Here, we describe the creation of virtual masks that allow for image-guided laser control; the photopolymerization of a micromolded PEGDA hydrogel, suitable for microfluidic network fabrication and pressure head-driven flow; the setup and use of a commercially available laser scanning confocal microscope paired with a femtosecond pulsed Ti:S laser to induce hydrogel degradation; and the imaging of fabricated microfluidic networks using fluorescent species and confocal microscopy. Much of the protocol is focused on the proper setup and implementation of the microscope software and microscope macro, as these are crucial steps in using a commercial microscope for microfluidic fabrication purposes that contain a number of intricacies. The image-guided component of this technique allows for the implementation of 3D image stacks or user-generated 3D models, thereby allowing for creative microfluidic design and for the fabrication of complex microfluidic systems of virtually any configuration. With an expected impact in tissue engineering, the methods outlined in this protocol could aid in the fabrication of advanced biomimetic microtissue constructs for organ- and human-on-a-chip devices. By mimicking the complex architecture, tortuosity, size, and density of in vivo vasculature, essential biological transport processes can be replicated in these constructs, leading to more accurate in vitro modeling of drug pharmacokinetics and disease.

This protocol outlines the implementation of image-guided, laser-based hydrogel degradation to fabricate vascular-derived, biomimetic microfluidic networks embedded in poly(ethylene glycol) diacrylate (PEGDA) hydrogels. These biomimetic microfluidic systems may be useful for tissue engineering applications, generation of in vitro disease models, and fabrication of advanced "on-a-chip" devices.

תמונה מונחה, ייצור מבוסס-לייזר של רשתות Microfluidic הנגזרות דם

This detailed protocol outlines the implementation of image-guided, laser-based hydrogel degradation for the fabrication of vascular-derived microfluidic ...

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.

פלטפורמה מבוססת Photoresist ביוסנסור אלקטרוכימי Microfluidic הסרט יבש: ייצור המכשיר, הכנה על שבב Assay, ותפעול המערכת

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

Rat Model of Adhesive Capsulitis of the Shoulder

This proposal aims to create an in vivo rat model of adhesive capsulitis for researching potential treatment options for this condition and other etiologies of comparable arthrofibrosis. The model includes extra-articular fixation of the shoulder in rats via scapular to humeral suturing, resulting in a secondary contracture without invading the intra-articular space and resulting in decreased rotational ROM and increased joint stiffness.
We used 10 Sprague-Dawley rats for the purpose of this study. Baseline ROM measurements were taken before glenohumeral immobilization. The rats were subjected to 8 weeks of immobilization before the fixation sutures were removed and changes in ROM and joint stiffness were evaluated. To evaluate whether immobilization resulted in a significant reduction in ROM, changes in kinematics were calculated. ROM was measured at each time point in the follow-up period and was compared to the baseline internal and external ROM measurements. In order to evaluate the stiffness, joint kinetics were calculated by determining the differences in torque (text and tint ) needed to reach the initial external rotation of 60&#176; and initial internal rotation of 80&#176;.
After the removal of the extra-articular suture fixation on follow-up day 0, we found a 63% decrease in total ROM compared to baseline. We observed continuous improvement until week 5 of follow-up, with the progress slowing down around a 19% restriction. On week 8 of follow-up, there was still an 18% restriction of ROM. Additionally, on follow-up day 0, we found the torque increased by 13.3 Nmm when compared to baseline. On week 8, the total torque was measured to be 1.4 &#177; 0.2 Nmm higher than initial measurements. This work introduces a rat model of shoulder adhesive capsulitis with lasting reduced ROM and increased stiffness.

This protocol presents an in vivo rat model of adhesive capsulitis. The model includes an internal fixation of the glenohumeral joint with extra-articular suture fixation for an extended time, resulting in a decreased rotational range of motion (ROM) and increased joint stiffness.