LAUSR

Abstract This paper reports the discovery that free-standing rubbery fiber mats can be electrospun from polyisobutylene-based thermoplastic elastomer/poly(ethylene glycol) mixtures from a THF-toluene solution. Direct contact and elution cytotoxic assays of these mats showed no cytotoxic response. Electrospinning the polymers mixed with Zafirlukast (ZAF), an anti-inflammatory drug, resulted in complete encapsulation of ZAF into the fibers, without the need of coaxial spinning. Release profiles followed close to a Fickian diffusion model. Significantly, ZAF-eluting fiber mats successfully inhibited the target cysteinyl leukotriene receptors in vitro , known to reduce inflammation. Local application of these mats could have the potential to reduce capsular contracture, the major complication reported for silicone rubber breast prostheses due to inflammatory response. A recent study using a poly(lactic- co -glycolic acid) polymer coating with a similar drug demonstrated capsule thickness reduction in vivo , but suggested that higher doses and slower release rates would be more effective. We believe our slower releasing mats with higher loading could be better at mitigating capsular contracture.