Dsc 60 instrument

A Shimadzu (Kyoto, Japan) DSC-60 instrument was used to record the DSC thermograms. Samples (3-5 mg) were accurately weighed and sealed in aluminum crimp cells. The samples were heated from 25 to 250°C with a heating rate of 10°C/min and a nitrogen gas purge of 35 mL/min. The onset temperatures of the thermal events are reported and the glass transition temperatures (T g ) were determined from heating scans. For non-isothermal recrystallization studies of amorphous sulfadoxine, approximately 5 mg of the amorphous form was accurately weighed and sealed into aluminum crimp cells. For the samples to which crystalline sulfadoxine was added as seeds, approximately 4 mg of neat amorphous sulfadoxine and 1 mg of crystalline sulfadoxine were weighed into aluminum crimp cells. The same nitrogen gas purge was used as mentioned above. Heating rates of 2, 5, 7, 10, 15, and 20°C/min were used (n=3). For the resulting Kissinger, plots the peak temperatures for the recrystallization of amorphous sulfadoxine was used.

Samples of pure clozapine, CAPs and the prepared co-amorphous dispersion formulations (5 mg each) were individually fi lled into aluminium fl at-bo omed pans and heated in a DSC-60 instrument (Shimadzu, Japan) in nitrogen atmosphere. The heating temperature used for the crystalline components was set between 20 and 300 o C with a heating rate 10 o C min -1 . To accurately detect glass transition (T g ) of the prepared co-amorphous dispersions, another heating range was selected (-40 to 300 °C). Comparisons were made with amorphous clozapine prepared by melting at 190 °C, followed by quench cooling under liquid nitrogen (14) (link).