Pharma Excipients

Test and Method

Specification

Result

Identification A (USP)

Mix 0.5 g with 10 mL of 3 N hydrochloric acid, filter, and neutralize the filtrate to litmus paper with 6 N ammonium hydroxide: the neutralized filtrate so obtained responds to the tests for Calcium<191>

Complies

Identification B (USP)

Prepare a bead by fusing a few crystals of sodium ammonium phosphate on a platinum loop in the flame of a gas burner. Place the hot, transparent bead in contact with the specimen of Calcium Silicate, and again fuse. Silica floats about in the bead, producing, upon cooling, an opaque bead having a web-like structure.

Complies

pH(USP)

8.4 – 10.2

9.1

Loss on ignition(USP)

NMT 20.0 % . dry at 105,2 Hrs

10.8

Heavy metals(USP)

20 µg per g. max

Complies

Lead(USP)

limit is 0.001%.

Complies

fluoride(USP)

The limit is 10 µg per g.

Complies

Assay for silicon dioxide(USP)

90.0% -  110.0%

102

Assay for calcium oxide(USP)

90.0% and 110.0%

104

Ratio of SiO2 to CaO(USP)

between 1.3 and 20

Complies

Sum of CaO, SiO2, and Loss on ignition—(USP)

NLT 90.0%

Complies