Thermoanalytical Investigation of Some Sulfone-Containing Drugs

Table 4

Degree of purity and melting point of Dapsone, dimethyl sulfone, and Topiramate in drug substances by DSC, melting point apparatus, and pharmacopoeial and reported methods.

Drugs	Degree of purity%		Melting point (°C)
	DSC*	Pharmacopoeial/reported	DSC	Mp apparatus	Pharmacopoeial/reported
Dapsone	99.66	100.29**	175.62	177	175–181
Dimethyl sulfone	99.73	99.36***	106.99	109	108–110
Topiramate	98.27	98.00****	122.41	125	122–126

*Mean of five instrumental run.
**Official BP 2010.
***Manufacturer GC method supplied by Eva Pharma, Egypt.
****Official USP 2011.