Magnesium stearate is often used as an anti-adherentin the manufacture of medical tablets, capsules, and powders. In this regard, the substance is also useful because it has lubricating properties, preventing ingredients from sticking to manufacturing equipment during the compression of chemical powders into solid tablets; magnesium stearate is the most used lubricant for tablets. However, it might cause lower wettability and slower disintegration of the tablets and slower and even lower dissolution of the drug.
Magnesium stearate can also be used efficiently in dry coating processes. In the creation of pressed candies, magnesium stearate acts as a release agent and it is used to bind sugar in hard candies such as mints.
Magnesium stearate is a common ingredient in baby formulas.
CERTIFICATE OF ANALYSIS
| Product | Magnesium Stearate |
| Grade | IP/BP/USP |
| TESTS | RESULTS | SPECIFICATION |
| Description | Complies | A Very Fine, Light, White Powder, Odorless or with a faint odor of stearic acid; unctuous and free from grittiness |
| Solubility | Complies | Practically insoluble in water, in ethanol & in ether |
| Identification: | ||
| (A) Freezing Point | 56O C | Not Less Than 53O C |
| (B)Acid Value | Complies | The Acid Value of the fatty acid is 195 to 210 |
| (C)Fatty Acid Composition | Complies | As Per IP |
| (D)Reaction on Magnesium | Complies | Solution A gives the reaction of magnesium |
| Appearance of solution | Complies | Solution A is not more intensely colored than reference solution YS6 |
| Appearance of solution of the fatty acids. | Complies | The solution is clear, and not more intensely colored than reference solution YS5 |
| Acidity of Alkalinity | 0.004 ml of 0.1 M HCI is Required | NMT 0.05 ml of 0.1M HCI or 0.1 M NaOH is required to change the color of the solution |
| Acid value of the fatty acids | 208.2 | 195 to 210 |
| Free Stearic acid | 1.41% | NMT 3 % |
| Zinc Stearate | Complies | No violet Precipitate is formed |
| Heavy Metals | Complies | Max 20 ppm |
| Chlorides | Complies | Max 250 ppm |
| Sulphates | Complies | Max 0.6% |
| Loss on Drying at 105OC,1.0 g | 2.86% | NMT 6.0% |
| Bulk Density (In House) | 0.22 g/cc | 0.15-0.3 g/cc |
| Assay | 4.75% | 3.8% -5.0% Mg on the Dried Basis |
| The Fatty acid Fraction Stearic Acid | Complies | NLT 40.0% |
| Sum of stearic acid and palmitic acid | Complies | NLT 90.0% |
| TAMC | <1000 cfu/g | Acceptance criterion 103 cfu/g |
| TYMC | <100 cfu/g | Acceptance criterion 102 cfu/g |
| Escherichia coli | Absent | Absent |
| Salmonella | Absent | Absent |