Development and characterization of aceclofenac-LDH/alginate porous microspheres for pH-responsive drug release

The antipyretic and anti-inflammatory drug aceclofenac (ACF) causes the serious side effect of adverse gastrointestinal reactions. With the aim to provide sustained action and prevent drug release into the stomach, aceclofenac-LDH/alginate porous microspheres were developed via an emulsion method to achieve sustained and pH-responsive drug release. The obtained microspheres were characterized by XRD, SEM, FT-IR, and TG-DSC. The SEM images show a porous morphology of microspheres with diameters of 2 µm. TG-DSC data prove that the thermal stability was greatly increased by the interaction of the LDH and alginate. In vitro drug release was studied in PBS (pH 7.4 and 4.0) at 37 °C. Compared with the physical mixture and ACF-LDH nanohybrids, ACF release from the porous LDH/Alg microspheres was 50% (pH 4.0) within 16 h, whereas 62% of the drug was released at pH 7.4, indicative of a sustained and pH-responsive drug release profile.