Adsorption of praziquantel enantiomers on chiral cellulose tris 3-chloro, 4-methylphenylcarbamate by frontal analysis: Fisherian and Bayesian parameter estimation and inference.

Praziquantel (PZQ) is an anthelmintic chiral pharmaceutical utilized in schistosomiasis treatment, commonly sold as a racemate, whose primary active molecule is the enantiomer L-(-)-PZQ. The development of new pharmaceutical formulations contenting L-(-)-PZQ has mobilized worldwide efforts from the academy and private companies. Several processes have been proposed to produce pure L-(-)-PZQ, including racemate resolution by preparative chromatography. The design of complex chromatographic processes such as SMB requires accurate information about the adsorption isotherm models and other system parameters and well-quantified uncertainties. We obtained the adsorption isotherms of both PZQ enantiomers using the Frontal Analysis (FA) technique. The associated uncertainties and model confidence bands were calculated from Fisherian and Bayesian approaches. Parameter uncertainties from both methods presented reasonable agreement. Bayesian inference allowed calculating conservative confidence intervals for the parameters, the isotherm curves and the experimental profiles related to FA. Predicted confidence intervals varied from 5.6% to 14% for parameters, 3.9% to 7.1% for the isotherms and 2.02% to 2.22% for the concentration on FA profiles. The estimated nuisance factor agreed with the experimental relative standard deviation and could be applied to predict experimental variances when the same is absent.