Solubility of Lamotrigine and Diazepam in Propylene Glycol plus Water plus Carboxymethyl Cellulose at a Temperature of 298.2 K

Abstract

The simultaneous effects of propylene glycol and carboxymethyl cellulose (CMC) on the solubility of two antiepileptic drugs, 6-(2,3-dichlorophenyI)-1,2,4-triazine-3,5-diamine (commonly known as lamotrigine) and 7-chloro-1-methyl-5-pheny1-3H-1,4-benzodiazepin-2-one (commonly known as diazepam), at T= 298.2 K were investigated. The aqueous solubility of drugs in the presence of propylene glycol and different concentrations of CMC [(0.02, 0.2, 1, and 2) g.L(-1) increased. The data were fit to a modified version of the Jouyban Acree model for modeling the simultaneous effects of the cosolvent and polymer on the solubility of drugs. The overall mean relative deviation (MRD) was 15.8 To, and the solubilities of drugs could be predicted at different propylene glycol and CMC concentrations using an interpolation technique.