Poly(anhydride‐ester) and Poly(N‐vinyl‐2‐pyrrolidone) Blends: Salicylic Acid‐Releasing Blends with Hydrogel‐Like Properties that Reduce Inflammation

Abstract

Polymers such as poly(N-vinyl-2-pyrrolidone) (PVP) have been used to prepare hydrogels for wound dressing applications but are not inherently bioactive. For enhanced healing, the release of physically admixed therapeutics from hydrogels has been evaluated, but with limited control over drug release profiles. To overcome these limitations, PVP was blended with salicylic acid-based poly(anhydride-esters) (SAPAE) and shown to exhibit hydrogel properties upon swelling. In vitro release studies demonstrated that the chemically incorporated drug (SA) was released from the polymer blends over 3–4 days in contrast to 3 hours, as observed with diffusion-controlled hydrogels. Generally, blends of higher PVP content displayed greater swelling values and faster SA release. The polymer blends significantly reduce the inflammatory cytokine, TNF-α, in vitro without cytotoxic or anti-proliferative effects, further demonstrating their potential as a wound dressing with enhanced healing and decreased scar tissue formation.

Salicylic acid (SA)‐eluting bone regeneration scaffolds with interconnected porosity and local and sustained SA release

“…The initial lag period is considered beneficial for bone regeneration, as it allows sufficient initial inflammation to develop and initiate subsequent healing . The later sustained SA release can mitigate the chronic inflammation caused by diabetes and ultimately enhance bone healing …”

Polyactives: controlled and sustained bioactive release via hydrolytic degradation

“…94 These different properties allow a broad range of applications of the SA-based PAEs, such as flexible wraps, wound dressing, nerve guidance conduits, etc. 93, 94 …”

Sustained, localized salicylic acid delivery enhances diabetic bone regeneration via prolonged mitigation of inflammation

“…(A)], which can help resolve the high level of inflammation that persists in diabetic animals and may hinder bone formation . After 1 week, consistently low levels of local SA (∼0.5 mg mL −1 ) that is comparable to its IC50 (5 µg mL −1 to 20 mg mL −1 ) were released, which could ameliorate the chronic inflammation impairing bone healing in diabetic animal …”