CELL LADEN ALGINATE/ALBUMIN HYDROGEL FIBERS FOR POTENTIAL SKIN TISSUE ENGINEERING APPLICATIONS

Alginate hydrogel fibers are receiving a great attention for tissue engineering applications. However, an important limitation of alginate is that it does not provide cell adhesion motifs. In this work, albumin was blended with alginate to improve the compatibility of alginate fibers with cells. Cell laden alginate/albumin fibers, potentially usable for skin regeneration, were obtained through a spinning process, by extruding an alginate/albumin solution containing cells into a calcium chloride solution. Cell laden pure alginate fibers were prepared for comparison. Plain alginate and alginate/albumin fibers were also produced. Morphological, mechanical and functional properties of the produced fibers were investigated. In addition, the ability of the fibers to release albumin and to support the viability and growth of A549 cells embedded into them was studied. Fibers with a uniform shape and an average diameter within the range 550-570 mu m were produced. The water content was 94.6 +/- 0.4% for alginate fibers, and 94.9 +/- 0.3% for alginate/albumin fibers. Stress-strain tests showed, up to a strain value of 20%, the same Young's modulus for the produced fibers, regardless of the presence of albumin. Overall, obtained results demonstrated that morphology, size, hydrophilicity and mechanical properties were not affected by albumin. Albumin was gradually released over a period of 4 days, with a residual amount (13%) remaining into the fibers. Viability test was carried out on A549 cells, laden inside alginate and alginate/albumin fibers, to evaluate cell proliferation ability. A favorable effect of albumin on the loaded cells was evidenced by a faster kinetics of growth.