Aspirin Drug Intercalated into Zinc-Layered Hydroxides as Nanolayers: Structure and In Vitro Release

Abstract

Zinc layered hydroxides (ZLHs) can be used as host materials for drug-ZLH host–guest structures. Aspirin with 0.1 and 0.4 M were intercalated into zinc layered hydroxides to form aspirin nanocomposites; ASPN1 and ASPN4, respectively. From XRD and software, the interlayer spacing of ASPN1 and ASPN4 was 15.2 Å. The result coupled with molecular geometry calculation indicates that the spatial orientation of the drug in the ZLH was monolayer for ASPN1 and ASPN4 nanocomposites. The release of the aspirin from ASPN4 nanocomposite at pH 6.8 is 35%, compared to 98% at pH 1.2, and followed Hixson model and Korsmeyer model for ASPN4 at pH 6.8 and pH 1.2, respectively. This result indicates sustained release of the drugs from their respective nanocomposites, and therefore these nanocomposites have good potential to be used as controlled-release formulation of the aspirin. The ASPN4 nanocomposite was highly effective to Escherichia coli compared to free aspirin, where the ASPN4 given 1.37 inhibition zone compared to aspirin which given 1.17 cm inhibition zone.