Dexamethasone-releasing biodegradable polymer scaffolds fabricated by a gas-foaming/salt-leaching method.

Dexamethasone, a steroidal anti-inflammatory drug, was incorporated into porous biodegradable polymer scaffolds for sustained release. The slowly released dexamethasone from the degrading scaffolds was hypothesized to locally modulate the proliferation and differentiation of various cells. Dexamethasone containing porous poly(D,L-lactic-co-glycolic acid) (PLGA) scaffolds were fabricated by a gas-foaming/salt-leaching method. Dexamethasone was loaded within the polymer phase of the PLGA scaffold in a molecularly dissolved state. The loading efficiency of dexamethasone varied from 57% to 65% depending on the initial loading amount. Dexamethasone was slowly released out in a controlled manner for over 30 days without showing an initial burst release. Release amount and duration could be adjusted by controlling the initial loading amount within the scaffolds. Released dexamethasone from the scaffolds drastically suppressed the proliferations of lymphocytes and smooth muscle cells in vitro. This study suggests that dexamethasone-releasing PLGA scaffolds could be potentially used either as an anti-inflammatory porous prosthetic device or as a temporal biodegradable stent for reducing intimal hyperplasia in restenosis.