Long-term drug release from electrospun fibers for in vivo inflammation prevention in the prevention of peritendinous adhesions

Physical barriers such as electrospun fibrous membranes are potentially useful in preventing peritendinous adhesions after surgery. However, inflammatory responses caused by degradation of barrier materials remain a major challenge. This study aimed to fabricate electrospun composite fibrous membranes based on drug-loaded modified mesoporous silica (MMS) and poly (l-lactic acid) (PLLA). Using a co-solvent-based electrospinning method ibuprofen (IBU)-loaded MMS was successfully and uniformly encapsulated in the PLLA fibers. The electrospun PLLA–MMS–IBU composite fibrous membranes showed significantly lower initial burst release (6% release in the first 12 h) compared with that of electrospun PLLA–IBU fibrous membranes (46% release in the first 12 h) in in vitro release tests. Moreover, the release from PLLA–MMS–IBU was also for significantly longer than that from PLLA–IBU (100 vs. 20 days). In animal studies both PLLA–IBU and PLLA–MMS–IBU showed improved anti-adhesion properties and anti-inflammatory effects compared with PLLA fibrous membrane alone 4 weeks after implantation. Further, animals implanted with PLLA–MMS–IBU for 8 weeks showed the lowest inflammation and best recovery compared with those implanted with PLLA–IBU and PLLA, most likely as a result of its long-term IBU release profile. Therefore, this study provides a platform technique for fabricating fibrous membranes with long-term sustained drug release characteristics which may function as a novel carrier for long-term anti-inflammation and anti-adhesion to prevent peritendinous adhesions.