Tramadol hydrochloride/montmorillonite composite: Preparation and controlled drug release

The adsorption of tramadol hydrochloride (TH) by montmorillonite (MMT) was investigated, to obtain a controlled drug release system. The adsorption isotherm was fitted by the Langmuir model and followed the pseudo-second-order kinetics. The composite was characterized by XRD, FTIR and TG-DTA. TH was intercalated into MMT in vertical orientation giving a basal spacing of 1.99 nm. Release of the intercalated TH was studied in simulated gastric fluid (SGF, pH = 1.2) and simulated intestinal fluid (SIF, pH = 7.4) at 37 °C. Controlled release of TH from TH/MMT was observed.