We have been using a heat conduction microcalorimeter to measure enthalpies of dissolution of slightly soluble solids. Recently we did report the testing of the prototype and we are now extending the previous investigation to measurements with organic solvents. In the present work we use DMSO due to its importance in the pharmaceutical industry. The importance of the applications of enthalpies of solution in organic solvents calls for the need to find a substance that can be used in the future for chemical calibration in these solvents. Attempts for proposing such a substance have also been a goal for our research group. The enthalpies of solution of paracetamol and sodium diclofenac were measured in DMSO and in phosphate buffer (pH 6.91) at 298.15 K. We show that it is possible to obtain very good results with DMSO as solvent for these two drugs on our dissolution microcalorimeter. Nevertheless, due to their slow and low enthalpy of dissolution in this solvent, they cannot be seen as good candidates for test substances.
Compounds
#
Formula
Name
1
C2H6OS
dimethyl sulfoxide
2
C8H9NO2
N-acetyl-p-aminophenol
3
C14H10Cl2NNaO2
sodium diclofenac
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.