Preparation of azithromycin microcapsules by a layer-by-layer self-assembly approach and release behaviors of azithromycin

A novel preparation method of azithromycin (AZI) microcapsules based on hollow polyelectrolyte (PE) microcapsules, which were prepared by layer-by-layer self-assembly onto the surface of silica microsphere (SiO2) followed by core dissolution has been investigated. The prepared AZI/PE microcapsules with an average diameter 1.2 μm possess homogeneous size and regular spherical shape. FTIR spectra and XRD patterns indicated that AZI molecular structure was not changed and AZI crystal state changed from monohydrate to dihydrate. The drug release experimental results showed an obvious improvement in the dissolution rate of the prepared AZI/PE microcapsules in comparing with AZI raw material drug powder.