NATIONAL BIBLIOGRAPHY NUMBER
Number
۲۳۱۸۸پ
LANGUAGE OF THE ITEM
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per
TITLE AND STATEMENT OF RESPONSIBILITY
Title Proper
داربست‌صهای نانوکامپوزیتی مهندسی بافت استخوان بر پایه پلیمرهای طبیعی و سنتزی حاوی ترکیبات گرافن اکسید و خاک رس؛ تهیه و مطالعه ویژگی ها
Parallel Title Proper
Bone Tissue Engineering Nanocomposite Scaffolds Based on Natural and Synthetic Polymers Incorporating Graphene Oxide and Clay Compounds; Preparation and Characterization Studies
First Statement of Responsibility
/هاله بخت خوش حق
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: شیمی
Date of Publication, Distribution, etc.
، ۱۳۹۸
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، راشدی
PHYSICAL DESCRIPTION
Specific Material Designation and Extent of Item
۱۶۱ص
NOTES PERTAINING TO PUBLICATION, DISTRIBUTION, ETC.
Text of Note
چاپی - الکترونیکی
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
دکتری
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شیمی کاربردی
Date of degree
۱۳۹۸/۱۱/۱۶
Body granting the degree
تبریز
SUMMARY OR ABSTRACT
Text of Note
پلیمرهای طبیعی به عنوان یکی از منابع قابل توجه در صنایع پزشکی و مطالعات زیستی مورد استفاده هستند .زیست‌صسازگاری، زیست‌صتخریب‌صپذیری، فراوانی و قیمت پایین پلیمرهای طبیعی از مزایای این دسته مواد هستند .با این وجود، محدودیت‌صهای این دسته از مواد از قبیل انحلال بسیار بالا در محیطصهای آبی، نرخ تخریب بالا در داخل بدن، خواص مکانیکی ضعیف، لزوم استفاده از فرآیند شیمیایی و فیزیکی از جمله اصلاح شیمیایی و تولید مواد کامپوزیتی و هیبریدی با هدف بهره‌صگیری از مزایای اجزای تشکیل‌ص-دهنده را افزایش می‌صدهند .در پروژه تحقیقی حاضر داربست‌صهای نانوکامپوزیتی پلیمری بر پایه پلیمرهای طبیعی کیتوسان و ژلاتین با هدف مطالعه تاثیر مواد بر پایه‌ص گرافن و خاک رس بر ویژگی‌صهای داربست تهیه شده و ویژگی‌صهای ساختارهای تهیه شده مورد بررسی قرار گرفت .در این راستا گرافن اکسید با استفاده از روش هامر اصلاح شده از گرافیت تهیه شد و ساختار آن با استفاده از آنالیزصهایXRD ،IR- FT،SEM ، طیف‌صسنجی رامان و پتانسیل زتا شناسایی گردید .در مراحل مختلف پروژه از گرافن اکسید تهیه شده به عنوان ماده اولیه و افزودنی در ساخت داربست‌صهای نانوکامپوزیتی استفاده شد .پتانسیل داربست-های تهیه شده به عنوان داربست‌صهای مهندسی بافت استخوان مورد بررسی قرار گرفت .با تهیه داربستGel- CS،Gel/GO- CS،Gel/MMT - CSوGel/GO/MMT - CSاثر هم‌صافزائی گرافن اکسید و خاک رس مونتموریلونیت بر ویژگی‌صهای داربست مورد بررسی قرار گرفت .توانایی داربست‌صهای تهیه شده در جذب آب نشان داد که حضور همزمان دو افزودنی باعث بهبود خاصیت جذب آب داربست تا حدود ۱/۴ برابر می-شود .همچنین بالاترین میزان چگالی برای داربستGel/GO/MMT - CSمشاهده شد (g/cm۳ ۰/۰۲۷ (که در نهایت منجر به افزایش قابل توجه در خواص مکانیکی داربست شد .به طوری که مدول الاستیک داربستGel/GO/MMT - CSاز MPa ۱۷/۵۶ برای داربستGel - CSبه MPa ۲۲/۷۳ افزایش یافت .همچنین استحکام فشاری داربست از MPa ۰/۱۴ برای داربستGel - CSبه مقدار MPa۰/۲۲۶۵ افزایش نشان داد .با حضور گرافن اکسید و مونتموریلونیت در بستر داربست میزان جذب پروتئین نسبت به داربستGel - CSبه حدود دو برابر افزایش یافت .مطالعات سمیت سلولی نشان داد نه تنها مواد افزوده شده به ماتریکس پلیمری داربست سمیتی برای سلول نشان نمی‌صدهند، بلکه باعث افزایش رشد سلولی تا حدود ۳۰ بعد از ۷۲ ساعت از شروع کشت سلولی می‌صشوند
Text of Note
for PCL. Due to unstable dispersion of halloysite in PCL higher concentrations than 5 would not end in a higher decrease in contact angle. Also, PCL+5 HNTs scaffold had more uniform nanofiber morphology than both PCL and nanocomposite scaffolds. PCL+5 HNTs scaffold showed a significant increase in tensile strength of scaffold in comparison to PCL scaffold, while protein adsorption improvement was not significant. Both PCL and PCL+5 HNTs samples provided a proper environment for cell growth ░from 135.53 ░Naturally found polymers are considered valuable candidates in the medical industry and biological studies. Biodegradability, biocompatibility, abundance, and cost-effectiveness are some outstanding features of natural polymers, while some limitations including high solubility in aqueous media, high rate of degradation in-vivo and in-vitro, poor mechanical properties obligate the user to modify their properties using chemical and physical procedures along with preparing composite material by benefiting from positive features of all components. In this work nanocomposite scaffolds based on chitosan and gelatin are designed to investigate the effect of graphene-based materials on the properties of scaffolds. In this regard, graphene oxide was prepared using the Hummers method and the chemical structure was studied by XRD, FT-IR, SEM, Raman spectroscopy, and Zeta potential. In every step of the project, GO was used as an additive to prepare the nanocomposite scaffold and the potential of the prepared structures to be used as a bone tissue engineering scaffold. To investigate the synergistic effect of GO and MMT, CS-Gel, CS-Gel/GO, CS-Gel/MMT, and CS-Gel/GO/MMT scaffolds were prepared with the same amount of GO and MMT (1 wt). The ability of the scaffold to absorb water proved that both additives have an impact on the water absorption ability of scaffold. The highest value of density was observed for the CS-Gel/GO/MMT scaffold, which ended in higher mechanical properties of scaffold. Elastic modulus of the CS-Gel/GO/MMT scaffold was 22.73 MPa from 17.56 MPa for CS-Gel. Also, the compressive strength of the scaffold was observed to be 0.14 MPa for CS-Gel and 0.2265 MPa for CS-Gel/GO/MMT. The double amount of protein absorption resulted from the simultaneous presence of GO and MMT in the scaffold matrix. Not only no cytotoxicity was observed for any of the scaffold samples, but also, GO and MMT increased the cell viability to about 30 of CS-Gel scaffold after 72 hours of cell seeding. In the second step of the project the effect of changing the functional groups of GO from carboxylic acid to amine groups on the physical, chemical, mechanical, and biological characteristics of the CS-Gel scaffold. GO was chemically modified to convert carboxylic acid functional groups on the GO plane edges to amine groups. The properties of GNH2 was studied XRD, FT-IR, SEM, Raman spectroscopy, and Zeta potential. Bigger pore size, pore interconnectivity, higher water absorption, and water retention ability, ability to keep the shape of the scaffold, higher porosity, and density resulted from incorporation of GO and GNH2 into scaffold structure. Coverage of GO and GNH2 with functional groups inducing biomineral precipitation caused higher biomineral formation on the scaffold surface in-vitro. A lower rate of biodegradation was observed for both nanocomposite samples. GO found to be a better additive from the viewpoint of mechanical properties improvement. Also, cell viability improved 10 and 4 respectively for Cs-Gel-GO and CS-Gel/GNH2 samples. In the third step of the project the effect of functionalization of GO with poly ethylene glycol as an additive for tissue engineering was investigated. PGO properties were studied by the use of FT-IR, Raman spectroscopy, and Zeta potential techniques. PGO was incorporated into the chitosan matrix and the properties of as-prepared scaffold were investigated. SEM imaging showed that pore shapes were spherical and homogeneous in the CS-PGO sample. Water absorption, water retention, porosity, and density of PGO was found to be improved in comparison to the CS scaffold. Although there was no significant improvement in the ability of the scaffold to retain its initial shape in aqueous media. A significant increase was observed in the compressive strength of the CS-PGO scaffold. The ability to keep their integrity in degradation media, to induce biomineral formation, increased protein absorption, higher cell viability, and cell attachment were some other benefits of PGO incorporation into scaffold structure. It should be mentioned that PGO presence ended in significantly higher hemolysis for the scaffold. At the fourth step of the work, PCL scaffold containing 5 , 10 , 15 , 20 , and 25 of HNTs were prepared and the physico-chemical, mechanical, and biological properties were investigated using FT-IR, XRD, SEM, and water contact angle studies. It was found that with 5 of HNTs the contact angle of water decreased to 111.15
PARALLEL TITLE PROPER
Parallel Title
Bone Tissue Engineering Nanocomposite Scaffolds Based on Natural and Synthetic Polymers Incorporating Graphene Oxide and Clay Compounds; Preparation and Characterization Studies
PERSONAL NAME - PRIMARY RESPONSIBILITY
بخت خوش حق، هاله
Bakhtkhosh Hagh, Haleh
PERSONAL NAME - SECONDARY RESPONSIBILITY
اولاد، علی، استاد راهنما
میرمحسنی، عبدالرضا، استاد مشاور
فرشی ازهر، فهیمه، استاد مشاور
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نمایه‌سازی قبلی
