Solubility of Amlodipine Besylate (Calcium Channel Blocker Drug) in Supercritical Carbon Dioxide: Measurement and Correlations

Solubilities of amlodipine besylate, a calcium channel blocker drug, in supercritical carbon dioxide (SCCO2) were measured for the first time in the temperature range of (308, 318, 328 and 338) K and the pressure range of (12 to 27) MPa with an equilibrium cell. Measured solubilities (in mole fraction) were in the range of 4.15 X 10(-6) to 11.7 X 10(-6) at 308 K, 7.04 X 10(-6) to 13.5 X 10(-6) at 318 K, 9.89 X 10(-6) to 18.5 X 10(-6 )at 328 K, and 11 X 10(-6) to 23 X 10(-6) at 338 K. Six empirical models, proposed by Chrastil, Garlapati-Madras (reformulated Chrastil), Mendez-Santiago-Teja, Bartle et al., Sodeifian et al., and Tippana-Garlapati were explored to correlate the experimental solubility data. Furthermore, solid-liquid equilibrium criteria were exploited for the development of new models. Moreover, the new models were tested by correlating the solubility data of standard compounds available in the literature such as naphthalene, anthracene, phenanthrene, benzoic acid and salicylic acid. However, among empirical models, the Sodeifian and Tippana models were observed to be better, and among new models, the expanded liquid model (case 4) was observed to be better at correlating the data.

Automated summary

The solubilities of amlodipine besylate in supercritical carbon dioxide were measured for the first time, and various empirical and new models were explored to correlate the experimental data. The study found that the expanded liquid model performed better in correlating the data than other models.