Stronsiyum Nano-Zeolit A ile Desenlenmiş Üç Boyut Baskılı Poli(Laktik Asit) Kemik Doku İskelelerinin Geliştirilmesi
Özet
The use of polymer based support materials in bone injuries continues with an increasing speed. Biocompatible, biodegradable properties of polymers and also their ability to be use in 3 dimensional (3D) printers for customized production can be given as the reasons for this increase. In this thesis, it is aimed to produce poly(lactic acid) (PLA) based support materials by using 3D printing fused deposition modeling (FDM) technology and modification their surface for bone injuries. For the purpose, the material to be printed in the 3D printer was drawn in SolidWorks program and then 3D printed with the nozzle tip temperature of 180 oC. The reason for choosing PLA for printing on a 3D printer is it is a biocompatible nature and being an FDA approved polymer. Also, PLA has suitable mechanical properties and biodegradation time for bone regeneration. The chemical and thermal properties of PLA before and after 3D printing were characterized by FTIR and DSC, respectively. As a second step, the synthesis of nano and micro zeolite A powders was carried out for the surface modification of PLA bone support materials. The dimensions of the synthesized nano zeolite A powders vary between 150-250 nm while the micro zeolite A powders are 1-1.5 μm. The characteristic peaks of nano and micro zeolite A powders were confirmed by XRD. Strontium (Sr), one of the most important element in bone structure, was loaded into zeolite A structures by ion exchange method. Sr loaded zeolite A structures were characterized with EDX and XRD. Three different methods have been applied for the surface modification of 3D printed PLA materials. The chemical, thermal and morphological properties of the products were examined. Biodegradation and cell culture performances of nano and micro zeolite A, Sr loaded nano and micro zeolite A decorated PLA bone support materials obtained by seeding and layer deposition technique were examined. Surface decoration with zeolites caused an increase in hydrophilic character and surface free energy of PLA surfaces. At the end of the 14th day, Saos cells showed higher Alkaline Phosphatase (ALP) activity on zeolite modified PLA surfaces compared to the control PLA. In the thesis study, positive and promising findings were obtained for the use of Sr-loaded zeolite A modified PLA structures as bone tissue scaffolds.
