Boric Acid

Boric Acid

H₃BO₃ 61.83

Boric acid (H₃BO₃) CAS RN®: 10043-35-3.

1 DEFINITION

Boric Acid contains NLT 99.5% and NMT 100.5% of boric acid (H₃BO₃), calculated on the dried basis.

2 IDENTIFICATION

A. Identification Tests—General 〈191〉, Chemical Identification Tests, Borate: Meets the requirements

3 ASSAY

Change to read:

Procedure

Sample solution: Dissolve 2 g of Boric Acid in 100 mL of a mixture of Glycerin and water (1:1), previously neutralized to phenolphthalein TS.

▲Titrimetric system

(See Titrimetry 〈541〉.)

Mode: Direct titration

Titrant: 1 N sodium hydroxide VS

Endpoint detection: Visual_{▲ (NF 1-May-2024)}

Analysis: Titrate the Sample solution with ▲Titrant._{▲ (NF 1-May-2024)} Discharge the pink color by the addition of 50 mL of glycerin, ▲previously▲ (NF 1-May-2024) neutralized to phenolphthalein TS, and continue the titration until the pink color reappears.

▲Calculate the percentage of boric acid (H₃BO₃) in the portion of Boric Acid taken:

Result = [(V_S × N_A × F)/W] × 100

V_S = volume of Titrant consumed by the Sample solution (mL)

N_A = actual normality of the Titrant (mEq/mL)

F = equivalency factor, 61.83 mg/mEq

W = weight of Boric Acid (mg)

▲ (NF 1-May-2024)

Acceptance criteria: 99.5%–100.5% on the dried basis

4 SPECIFIC TESTS

Loss on Drying 〈731〉

Analysis: Dry over silica gel for 5 h.

Acceptance criteria: NMT 0.5%

Solubility in Alcohol

Sample solution: 1 g in 10 mL of boiling alcohol

Acceptance criteria: It dissolves completely.

Completeness of Solution

Sample solution: 1 g in 25 mL of water

Acceptance criteria: It produces a clear solution.

Add the following:

▲Bacterial Endotoxins Test 〈85〉:

If labeled for use in preparing injectable dosage forms, it also meets the following requirements. The level of bacterial endotoxins is such that the requirement in the relevant dosage form monograph(s) in which Boric Acid is used can be met.

Where the label states that Boric Acid must be subjected to further processing during the preparation of injectable dosage forms, the level of bacterial endotoxins is such that the requirement in the relevant dosage form monograph(s) in which Boric Acid is used can be met._{▲ (NF 1-May-2024)}

5 ADDITIONAL REQUIREMENTS

Packaging and Storage: Preserve in well-closed containers.

Change to read:

Labeling:

▲Where Boric Acid is intended for use in the manufacture of injectable dosage forms, it is so labeled.

Where Boric Acid must be subjected to further processing during the preparation of injectable dosage forms to ensure acceptable levels of bacterial endotoxins, it is so labeled._{▲ (NF 1-May-2024)}