Development of aminolyzed polylactic acid-based porous films for pH-responsive sustained drug delivery devices

Biomaterial-based drug-carrying systems have scored enormous focus in the biomedical sector. Poly(lactic acid) (PLA) is a versatile material in this context. A porous and hydrophilic PLA surface can do this job better. We aimed to synthesize pH-responsive PLA-based porous films for uptaking and releasing amikacin sulfate in the aqueous media. The native PLA lacks functional/polar sites for the said purpose. So, we tended to aminolyze it for tailored physicochemical and surface properties. The amino (-NH₂) group density on the treated films was examined using the ninhydrin assay. Electron microscopic analyses indicated the retention of porous morphology after aminolysis. Surface wettability and FTIR results expressed that the resultant films became hydrophilic after aminolysis. The thermal analysis expressed reasonable thermal stability of the aminolyzed films. The prepared films expressed pH-responsive behaviour for loading and releasing amikacin sulfate drug at pH 5.5 and 7.4, respectively. The drug release data best-fitted the first-order kinetic model based on Akaike information and model selection criteria. The prepared PLA-based aminolyzed films qualified as potential candidates for pH-responsive drug delivery applications. This study could be the first report on pH-responsive amikacin sulfate uptake and release on the swellable aminolyzed PLA-based porous films for effective drug delivery application.