Study On Controllable Degradability Scaffolds For Tissue Engineering

The three-dimensional scaffolds is one important part in the study of tissue engineering, whether the scaffolds rate of degradation in vivo can match with the growth rate of repair tissue is one of the key factors which scaffolds are applied in the clinical treatment.poly(β-hydroxybutyrate)(PHB) is one of good biomaterials for tissue engineer -ing.however, the slow rate of degradation of the characteristics of its impact on the further application in tissue engineering. In this paper, poly(L-lactide)(PLLA), poly(ethyleneoxide)(PEO),and PHB was blended, attempting to improve slow de-g radation. The material's degradability was improved by adjusting the rate of blending. In addition, a new method was developed to prepare highly porous biodegradable scaffolds for tissue engineering, and the scaffolds was implanted in thea nimal body to observe its degradability.The cold crystallization behavior ,miscibility, crystallinity and degradability in the lysozyme/PBS buffer solution, of PHB/PLLA blends and PHB/PLLA/PEO ble -nds was studied by differential scanning calorimetry(DSC),Polarizing Optical Mcr oscopy(POM), Scanning Electron Microscopy(SEM).The results showed that, PHB was partly compatible with PLLA, and the miscibility of PHB with PLLA could be improved when PEO joining in the PHB/PLLA blends;the cold crystallizationt emperature and rate of PHB were independent of contents of PLLA in blends, a nd the cold crystallization temperatue of PLLA was also not affected by PHB, h owever, the crystallization rate became faster with increasing contents of PHB in blends; the crystallinity of blends depends on ratio of PHB and PLLA; In PHB/ PLLA/PEO blends, the cold crystallization temperature of PHB and PLLA were reduced .When PHB/PLLA blends containing less than 50% weights PLLA, thera te of blends degradation was slower than pure PHB;When containing up to 50% weights PLLA.the rate of the blends degradation was faster than pure PHB, but slower than pure PLLA; For blends PHB/PLLA/PEO containing 5% PEO, its ra te of degradation become faster in compared with PHB and PHB/PLLA blends,b efore 90 days, its rate was faster than that of pure PLLA, after 90 days.its rate was behind of pure PLLA, and remained PHB and PLLA became nearly miscibl...