Hồ Quốc Phong * , Tào Thế Dương , Trần Sỹ Nam Huỳnh Liên Hương

* Tác giả liên hệ (hqphong@ctu.edu.vn)

Abstract

Scaffold - a porous structure is an important component in tissue engineering, because it supports the formation of 3D structure. Therefore, this study was conducted to fabricate scaffold from polylactic acid (PLA). Nonsolvent induced phase separation method (NIPS) was applied and important factors affecting the formation of scaffold such as solvent types, polymer concentration, temperature of solvent system, the ratio of ethanol/water, and the ratio of solvent/nonsolvent (v/v) were investigated. Experimental results showed that when increasing the concentration of polymer and the water content in the nonsolvent were reducing pore size of scaffold. In contrast, when increasing the temperature and the ratio of solvents/nonsolvent were increasing the pore size of scaffold. Scaffold in the pore size of 42.4 μm could be prepared at condition of PLA 150 g/L, 40 ºC, the ethanol to water volume ratio of 96/4, the solvent/nonsolvent volume ratio of 1/20. In addition, the results of mechanical tests showed that tensile strength of scaffold decreased as the pore size increased. Tensile strength of scaffold in pore size of 42.4 μm was 65.5 MPa and its specific surface area was 25.7 m²/g.
Keywords: Porous structure, phase separation, polylactic acid, scaffold, tissue engineering

Tóm tắt

Scaffold - dạng cấu trúc khung xốp, là một thành phần quan trọng trong kỹ thuật mô vì nó góp phần vào việc tạo nên cấu trúc mô ba chiều. Vì thế, đề tài này được tiến hành nhằm nghiên cứu chế tạo scaffold từ polymer phân hủy sinh học polylactic acid (PLA). Phương pháp tách pha dung môi được sử dụng và các yếu tố ảnh hưởng đến sự hình thành scaffold như loại dung môi, nồng độ polymer, nhiệt độ trao đổi, tỉ lệ ethanol/nước của hệ dung môi trao đổi, tỉ lệ dung dịch và dung môi trao đổi được tiến hành khảo sát. Kết quả thí nghiệm cho thấy khi tăng nồng độ polymer và lượng nước của dung môi trao đổi làm giảm kích thước lỗ xốp. Ngược lại, khi tăng nhiệt độ trao đổi và tỉ lệ dung môi hòa tan/dung môi trao đổi làm tăng kích thước lỗ xốp. Scaffold có kích thước lỗ xốp 42,4 mm có thể được chế tạo ở nồng độ PLA là 150 g/L, nhiệt độ trao đổi là 40ºC, dung môi trao đổi có tỉ lệ ethanol/nước là 96/4, tỉ lệ thể tích dung môi hòa tan/dung môi trao đổi là 1/20. Ngoài ra, kết quả thử nghiệm cơ học cho thấy độ bền kéo của scaffold giảm khi tăng kích thước lỗ xốp. Scaffold với lỗ xốp 42,4 mm có độ bền kéo là 65,5 MPa và diện tích bề mặt riêng là 25,7 m2/g.
Từ khóa: Cấu trúc khung xốp, kỹ thuật mô, polylactic acid, scaffold, tách pha dung môi

Article Details

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