ABSTRACT:
In this study the significant effect of recrystalline azithromycin alone and with hydrophilic polymers and surfactant were studied on improving the solubility, dissolution rate and other physicochemical properties by neutralization technique. The raw crystals of azithromycin was dissolved in the 0.1N HCl and poured the azithromycin solution into 0.1N NaOH solution. To the precipitated or recrystallized azithromycin immediately add the aqueous solution of different hydrophilic polymers like HPMC, PEG-6000, and surfactant like Poloxomer during the stirring process at room temperature. After 30 minutes add chloroform drop wise as bridging liquid for agglomeration of recrystallized azithromycin with polymers and surfactant. The pure azithromycin drug substance and prepared recrystallized agglomerates with polymers and surfactants were evaluated in terms of solubility, drug content, dissolution rate, flowability, wettability and packability. The raw azithromycin drug and prepared recrystallized agglomerates were characterized by thermal behavior (Differential Scanning Calirometry-DSC), X-ray powder diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).The prepared recrystallized agglomerates with polymers HPMC and surfactant Poloxomer showed improvement in solubility, dissolution rates other physicochemical properties. The particle sizes of prepared recrystallized agglomerates were drastically reduced during precipitation process but increased after agglomeration with bridging liquid. The DSC showed reduced in the melting point enthalpy indicating disorder in the crystalline content. The XRD and FTIR also revealed a characteristic decrease in crystallinity and the chemistry of azithromycin in recrystallized agglomerates.