<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>Identification and characterization of different forms of methotrexate were carried out by crystallization from different solvents. Five different forms of the drug were obtained. Appearance of a desolvation endotherm in the DSC accompanied by mass loss in TGA for forms I, II, IV and V showed these forms to be acetonitrile solvate hydrate (form I), trihydrate (forms II and IV) and dimethylformamide solvate (form V), respectively. However, the desolvation peak was absent in form III (obtained from methanol) indicating the absence of any solvent of crystallization. This form was found to be partially crystalline by its XRPD pattern. Solution calorimetry was further used to differentiate between the forms as they differ in lattice energy, resulting in different enthalpies of solution. The dissolution and solubility profiles were correlated with the enthalpy of solution and subsequently with crystallinity of all the forms; the least endothermic form (form III) had the highest dissolution rate.</p></abstract>

Identification and characterization of different forms of methotrexate were carried out by crystallization from different solvents. Five different forms of the drug were obtained. Appearance of a desolvation endotherm in the DSC accompanied by mass loss in TGA for forms I, II, IV and V showed these forms to be acetonitrile solvate hydrate (form I), trihydrate (forms II and IV) and dimethylformamide solvate (form V), respectively. However, the desolvation peak was absent in form III (obtained from methanol) indicating the absence of any solvent of crystallization. This form was found to be partially crystalline by its XRPD pattern. Solution calorimetry was further used to differentiate between the forms as they differ in lattice energy, resulting in different enthalpies of solution. The dissolution and solubility profiles were correlated with the enthalpy of solution and subsequently with crystallinity of all the forms; the least endothermic form (form III) had the highest dissolution rate.

Characterization of solvatomorphs of methotrexate using thermoanalytical and other techniques

University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh-160014, India

Central Scientific Instruments Organization, Sector-30/C Chandigarh-16003, India

Department of Chemistry, Panjab University, Chandigarh-160014 India

Acta Pharmaceutica

Identification and characterization of different forms of methotrexate were carried out by crystallization from different solvents. Five different forms of the...

Characterization of solvatomorphs of methotrexate using thermoanalytical and other techniques

Published Online: Oct 09, 2009

Page range: 245 - 257

DOI: https://doi.org/10.2478/v10007-009-0024-9

Keywords
solvatomorf, pseudopolimorf, metotreksat, entalija otopine, kalorimetrija otopine, desolvatacija, topljivost

This content is open access.

Characterization of solvatomorphs of methotrexate using thermoanalytical and other techniques

Published Online: Oct 09, 2009

Page range: 245 - 257

DOI: https://doi.org/10.2478/v10007-009-0024-9

Keywordssolvatomorf, pseudopolimorf, metotreksat, entalija otopine, kalorimetrija otopine, desolvatacija, topljivost

This content is open access.

Keywords
solvatomorf, pseudopolimorf, metotreksat, entalija otopine, kalorimetrija otopine, desolvatacija, topljivost