Solubility measurement of an antihistamine drug (Loratadine) in supercritical carbon dioxide: Assessment of qCPA and PCP-SAFT equations of state

Abstract

Supercritical processes are being promoted in chemical, biochemical, pharmaceutical, agricultural and food processing industries. Obtaining the solubility data of solid pharmaceutical components in supercritical carbon dioxide (SC-CO2) is essential for the design of production process of a nanoparticle drug. In this study, the solubility of Loratadine as a second-generation histamine H1 receptor antagonist has been measured, for the first time, in SC-CO2 using the static method. The experiments were carried out at temperatures ranging from 308.15 to 338.15 K and pressures from 120 to 270 bar. The mole fraction results changed in the range of 0.45 × 10−5 to 1.3016 × 10−3. Solubility data of Loratadine were correlated by using the three different methods including seven density-based semi-empirical models, namely Chrastil, Sparks et al., Garlapati and Madras, Bartle et al., Méndez-Santiago and Teja (MST), Jouyban et al. and Bian et al. models, three equations of state (EoSs) namely Soave–Redlich–Kwong (SRK), quadrupolar cubic plus association theory (qCPA EoS) and the Perturbed-Chain Polar Statistical Associating Fluid Theory (PCP-SAFT EoS) and regular solution models. The accuracy of models were investigated by some statistical criteria, such as an average absolute relative deviation (AARD), adjusted correlation coefficient (Radj) and F value. The analysis of variance (ANOVA) results demonstrated the superiority of SRK model over other models for estimating the solubility of Loratadine in SC-CO2.