Development and Validation of Analytical Procedure for Elemental Impurities in Rosuvastatin Calcium Tablets by ICP-MS and Microwave Digestion

Table 4

Digestion procedure optimization.

	Acid added into the digestion tank	Mixture’s state after digestion	Mixture’s final state after dilution
1	5 mL of nitric acid	Muddy	Muddy
2	10 mL of nitric acid	Muddy	Muddy
3	9 mL of nitric acid plus 3 mL of hydrochloric acid	Muddy	Muddy
4	10 mL of nitric acid plus 2 mL of 30% hydrogen peroxide	Muddy	Muddy
5	5 mL of nitric acid plus 1 mL of concentrated sulfuric acid	Muddy	Muddy
6	5 mL of nitric acid plus 0.04 mL of hydrofluoric acid	Clear	Muddy
7	5 mL of nitric acid plus 0.05 mL of hydrofluoric acid	Clear	Clear
8	5 mL of nitric acid plus 0.06 mL of hydrofluoric acid	Clear	Clear
9	5 mL of nitric acid plus 0.1 mL of hydrofluoric acid	Clear	Clear
10	5 mL of nitric acid plus 0.5 mL of hydrofluoric acid	Clear	Clear