A novel method to get methotrexatum/layered double hydroxides intercalation compounds and their release properties Original Research Article

In this context, the methotrexatum/layered double hydroxides (MTX/LDHs) intercalation compounds have been synthesized by a mechanochemical–hydrothermal method, which involves a grinding process and subsequent hydrothermal treatment. The influence of R (molar ratio of Mg2+ to Al3+ to MTX) values on the structure and morphology of the intercalation compounds and their release properties were investigated systematically. The resulting compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), inductively coupled plasma (ICP), thermogravimetric (TG) and differential scanning calorimetry (DSC) analysis. All the results indicate that R value has significant influence on the intercalation of MTX anions into LDH interlayer and the optimal R value is 2:1:0.5. Furthermore, four dissolution–diffusion kinetic models were used to fit the in vitro release of MTX from LDH layers. The release process can be divided into two stages: firstly surface diffusion and secondly intraparticle diffusion. The study also revealed that the properties of the intercalation compounds is comparable to that obtained from standard methods such as co-precipitation method, but with time, solvent and energy saving.