TY - JOUR
T1 - Biofabrication of bundles of poly(lactic acid)-collagen blends mimicking the fascicles of the human Achille tendon
AU - Sensini, Alberto
AU - Gualandi, Chiara
AU - Cristofolini, Luca
AU - Tozzi, Gianluca
AU - Dicarlo, Manuela
AU - Teti, Gabriella
AU - Mattioli-Belmonte, Monica
AU - Focarete, Maria Letizia
PY - 2017/3/8
Y1 - 2017/3/8
N2 - Electrospinning is a promising technique for the production of scaffolds aimed at the regeneration of soft tissues. The aim of this work was to develop electrospun bundles mimicking the architecture and mechanical properties of the fascicles of the human Achille tendon. Two different blends of poly(L-lactic acid) (PLLA) and collagen (Coll) were tested, PLLA/Coll-75/25 and PLLA/Coll-50/50, and compared with bundles of pure PLLA. First, a complete physico-chemical characterization was performed on non-woven mats made of randomly arranged fibers. The presence of collagen in the fibers was assessed by thermogravimetric analysis, differential scanning calorimetry and water contact angle measurements. The collagen release in phosphate buffer solution (PBS) was evaluated for 14 days: results showed that collagen loss was about 50% for PLLA/Coll-75/25 and 70% for PLLA/Coll-50/50. In the bundles, the individual fibers had a diameter of 0.48± 0.14 µm (PLLA), 0.31±0.09 µm (PLLA/Coll-75/25), 0.33±0.08 µm (PLLA/Coll-50/50), whereas bundle diameter was in the range 300-500 µm for all samples. Monotonic tensile tests were performed to measure the mechanical properties of PLLA bundles (as-spun) and of PLLA/Coll-75/25 and PLLA/Coll-50/50 bundles (as-spun, and after 48 hour, 7 days and 14 days in PBS). The most promising material was the PLLA/Coll-75/25 blend with a Young modulus of 98.6±12.4 MPa (as-spun) and 205.1±73.0 MPa (after 14 days in PBS). Its failure stress was 14.2±0.7 MPa (as-spun) and 6.8±0.6 MPa (after 14 days in PBS). Pure PLLA withstood slightly lower stress than the PLLA/Coll-75/25 while PLLA/Coll-50/50 had a brittle behavior. Human-derived tenocytes were used for cellular tests. A good cell adhesion and viability after 14 day culture was observed. This study has therefore demonstrated the feasibility of fabricating electrospun bundles with multiscale structure and mechanical properties similar to the human tendon.
AB - Electrospinning is a promising technique for the production of scaffolds aimed at the regeneration of soft tissues. The aim of this work was to develop electrospun bundles mimicking the architecture and mechanical properties of the fascicles of the human Achille tendon. Two different blends of poly(L-lactic acid) (PLLA) and collagen (Coll) were tested, PLLA/Coll-75/25 and PLLA/Coll-50/50, and compared with bundles of pure PLLA. First, a complete physico-chemical characterization was performed on non-woven mats made of randomly arranged fibers. The presence of collagen in the fibers was assessed by thermogravimetric analysis, differential scanning calorimetry and water contact angle measurements. The collagen release in phosphate buffer solution (PBS) was evaluated for 14 days: results showed that collagen loss was about 50% for PLLA/Coll-75/25 and 70% for PLLA/Coll-50/50. In the bundles, the individual fibers had a diameter of 0.48± 0.14 µm (PLLA), 0.31±0.09 µm (PLLA/Coll-75/25), 0.33±0.08 µm (PLLA/Coll-50/50), whereas bundle diameter was in the range 300-500 µm for all samples. Monotonic tensile tests were performed to measure the mechanical properties of PLLA bundles (as-spun) and of PLLA/Coll-75/25 and PLLA/Coll-50/50 bundles (as-spun, and after 48 hour, 7 days and 14 days in PBS). The most promising material was the PLLA/Coll-75/25 blend with a Young modulus of 98.6±12.4 MPa (as-spun) and 205.1±73.0 MPa (after 14 days in PBS). Its failure stress was 14.2±0.7 MPa (as-spun) and 6.8±0.6 MPa (after 14 days in PBS). Pure PLLA withstood slightly lower stress than the PLLA/Coll-75/25 while PLLA/Coll-50/50 had a brittle behavior. Human-derived tenocytes were used for cellular tests. A good cell adhesion and viability after 14 day culture was observed. This study has therefore demonstrated the feasibility of fabricating electrospun bundles with multiscale structure and mechanical properties similar to the human tendon.
U2 - 10.1088/1758-5090/aa6204
DO - 10.1088/1758-5090/aa6204
M3 - Article
SN - 1758-5090
VL - 9
JO - Biofabrication
JF - Biofabrication
IS - 1
ER -