For Artemether: (By HPLC)
Test solution: Weigh and powder 20 tablets. Weight sample containing 40mg Artemether in 100ml of volumetric flask. Add 10ml of mobile phase and sonicate the sample to dissolve and makeup to the mark with mobile phase. Filter the solution and inject.
Reference solution: Weigh 20mg of Artemether reference standard in 50ml volumetric flask. Add 10ml of mobile phase and dissolve. Sonicate the sample & shake by mechanical means for 5 min, add 40ml of mobile phase.
Chromatographic system:
- A stainless steel column 15cm X4.6mm, packed with octadecylsilane bonded to porous silica (5µm) (such as thermo quest hypersil), C18
- Mobile Phase: Acetonitrile + water (60:40) and filter.
- Flow rate: 1.2ml per minute,
- Spectrophotometer set at 216nm,
- Injection volume: 20µl
Inject reference solution. The test is not valid unless the relative standard deviation for replicate injections for each peak is not more than 2.0 percent.
Inject reference solution and the test solution.
Calculate the content of Artemether in the tablet.
Formula:
Area of Test STD Wt.(mg) 100 Potency
—————–X——————-X——————–X—————–X Average weight
Area of STD 50 Test Wt.(mg) 100
Acceptance criteria: 90.0%-110.0%
For Lumefantrine: (By UVspectroscopy)
Reference solution: Weigh accurately about 50 mg of Lumefantrine reference standard, in 100 ml volumetric flask and dissolve in 10ml 0.1M methanolic HCl and make up the volume with 0.1M methanolic HCl. Take 1 ml of this solution in 25 ml volumetric flask and make up the volume with 0.1M methanolic HCl.
Test solution: Weigh and powder 20 tablets. Take sample equivalent to 50mg of Lumefantrine in 100 ml volumetric flask and dissolve in 10ml 0.1M methanolic HCl, sonicate the sample and make up volume with 0.1 M methanolc HCl. Filter, and take 1 ml of this solution in 25 ml volumetric flask and make up the volume with 0.1M methanolic HCl
Scan the dilutions from 200nm to 500nm in UV spectrophotometer. The solution gives absorbance maxima at about 303nm.
Formula:
Abs. of Test STD Wt.(mg) 1 100 25 Potency
—————–X————–X———X—————–X——–X———–X Average weight
Abs. of STD 100 25 Test Wt.(mg) 1 100
Acceptance criteria: 90.0%-110.0%