Nowadays, it is admitted to using of suitable carrier results in improving drug delivery such as nanotubes. So, multi-walled carbon nanotube (MWCNTs) has been proposed as a carrier (adsorbent) to improve the neurological Oxazepam (OZ) drug delivery. Freundlich, Temkin, and Langmuir isotherm models have been used in order to do assay adsorption of the OZ on the MWCNT. The maximum value of the isotherm constant (b = 0.14 L/mg) at 303 K temperature indicates stronger (better) adsorption of the OZ on the MWCNT surface in low concentrations (20 mg/L) and acidic pH; in fact, increasing of pH led to decreasing adsorption (60 ! 35.91 mg/g) and dehydrogenation of the OZ drug. Reaching to the equilibrium state after 90 min and negative value of the ΔH (−41.57 kJ/mol) shows that the OZ adsorption has fast kinetic and exothermic processes. These issues imply depending of the OZ adsorption on the OZ concentration and the weight of adsorbent in the adsorption process.

Todays, nanomaterial-based drug delivery systems can help to control the release of drugs. In this study, multiwalled carbon nanotubes (MWCNTs) were used as reliable carriers to enhance the delivery of carbamazepine (CBZ). The adsorption of the CBZ drugs on the MWCNTs was determined using three adsorption models, such as Langmuir, Freundlich, and Temkin. High values of isothermal constant (b) and separation factor (RL) confirm strong and reliable adsorption of the CBZ drug with concentration of 60 mg L -1 at 303 Kelvin in acidic medium.Another important point is that the adsorption value decreases with increasing pH. The negative value of enthalpy (ΔH) based on Vant-Hoff equation shows that the adsorption of the CBZ drugs on the MWCNTs exhibits fast pseudo-first order kinetics and exothermic process in 90 minutes. Moreover, the negative value of Gibbs free energy (ΔG) shows that the adsorption M a n u s c r i p t a c c e p t e d f o r p u b l i c a t i o n of the CBZ drug on the MWCNTs is a spontaneous process. Therefore, all the above parameters indicate that the MWCNTs can be considered as a reliable carrier for the adsorption, transfer, and controlled release of the CBZ drugs into the target cells with little side effects.