Article

Acrylic acid-grafted hydrophilic electrospun nanofibrous poly(L-lactic acid) Scaffold

Macromolecular Research (Impact Factor: 1.68). 10/2006; 14(5):552-558. DOI: 10.1007/BF03218723

ABSTRACT Biodegradable nanofibrous poly(L-lactic acid) (PLLA) scaffold was prepared by an electrospinning process for use in tissue
regeneration. The nanofiber scaffold was treated with oxygen plasma and then simultaneously in situ grafted with hydrophilic
acrylic acid (AA) to obtain PLLA-g-PAA. The fiber diameter, pore size, and porosity of the electrospun nanofibrous PLLA scaffold were estimated as 250∼750 nm,
∼30 µm, and 95%, respectively. The ultimate tensile strength was 1.7 MPa and the percent elongation at break was 120%. Although
the physical and mechanical properties of the PLLA-g-PAA scaffold were comparable to those of the PLLA control, a significantly lower contact angle and significantly higher ratio
of oxygen to carbon were notable on the PLLA-g-PAA surface. After the fibroblasts were cultured for up to 6 days, cell adhesion and proliferation were much improved on
the nanofibrous PLLA-g-PAA scaffold than on either PLLA film or unmodified nanofibrous PLLA scaffold. The present work demonstrated that the applications
of plasma treatment and hydrophilic AA grafting were effective to modify the surface of electrospun nanofibrous polymer scaffolds
and that the altered surface characteristics significantly improved cell adhesion and proliferation.

Keywordstissue engineering–PLLA scaffold–electrospun nanofiber–plasma treatment–acrylic acid grafting–fibroblast

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