C₃₄H₅₄Cl₂N₁₀O₁₄

DEFINITION

Aqueous solution of 1,1’-(hexane-1,6-diyl)bis[5-(4-chlorophenyl) biguanide] di-D-gluconate.

Content: 190g/L to 210 g/L.

CHARACTERS

Appearance: almost colorless or pale-yellowish liquid.

Solubility: miscrible with water, with not more than 3 parts of acetone and with not more than 5 parts of ethanol (96 per cent).

IDENTIFICATION

First identification: A, B

Second identification: B,C,D.

1. Infrared absorption spectrophotometry (2.2.24).

Preparation: to 1 mL add 40 mL of water R, cool in iced water, make alkaline to titan yellow paper R by adding dropwise, and with stirring, strong sodium hydroxide solution R and add 1 mL in excess. Filter, wash the precipitate with water R until the washings are free from alkali and recrystallise from ethanol (70 percent V/V)R. Dry at 100-105℃. Examine the residue.

Comparison: chlorhexidine CRS.

2. To 1 mL add 40 mL of water R, cool in iced water, make alkaline to titan yellow pater R by adding dropwise, and with stirring, strong sodium hydroxide solution R and add 1 mL in excess. Filter , wash the precipitate with water R until the washings are free from alkali and recrystallise from ethanol (70 per cent V/V) R. Dry at 100-105℃. The residue melts (2.2.14) at 132 ℃ to 136 ℃.

3. cetrimide R, 1 mL of strong sodium hydroxide solution R and 1 mL of bromine water R;  a deep red colour is produced.  

TESTS

Relative density(2.2.5): 1.06 to 1.07

pH(2.2.3): 5.5 to 7.0.

Dilute 5.0 mL to 100 mL with carbon dioxide-free water R.

Chloroaniline: maximum 0.25 per cent, calculated with reference to chlorhexidine digluconate at a nominal concentration of 200 g/L.

Dilute 2.0 mL to 100 mL with water R. To 10 mL of this solution add 2.5 mL of dilute hydrochloric acid R and dilute to 20 mL with water R. Add rapidly and with thorough mixing after each addition: 0.35 mL of sodium nitrite solution R, 2 mL of a 50g/L solution of amomonium sulfamate R, 5 mL of a 1 g/L solution of naphthyle thylenediamine dihydrochloride R, 1 mL of ethanol(96 per cent) R; dilute to 50.0 mL with water R and allow to stand for 30 min. Any reddish-blue colour in the solution is not more intense than that in a standard prepared at the same time and in the same manner using a mixture of 10.0 mL of a 0.010g/L solution of chloroaniline R in dilute hydrochloric acid R and 10 mL of water R instead of the dilution of the preparation to be examined.

Related substances.

Liquid chromatography(2.2.29)

Test solution.

Dilute 5.0 mL of the preparation to be examined to 50.0 mL with the mobile phase. Dilute 5.0mL of this solution to 50.0 mL with the mobile phase.

Reference solution（a）

Dissolve 15mg of chlorhexidine for performance test CRS in the mobile phase and dilute to 10.0 mL with the mobile phase.

Reference solution（b）

Dilute 3.0 mL of the test solution to 100 mL with the mobile phase.

Reference solution (c)

Dilute 1.0 mL of reference solution (b) to 50 mL with the mobile phase

Column:

-size: l=0.2m, φ=4 mm；

Stationary phase: ortadecylsilyl silica gel for chromatography R (5μm)

Mobile phase: solution of 2.0g of sodium octanesulfonate R in a mixture of 120mL of glacial acetic acid R, 270 mL of water R and 730 mL of methanol R

Detection: spectrophotometer at 254nm

Equilibration: with the mobile phase for at least 1 hour.

Injection: 10μL

Run time: 6 times the retention time of chlorhexidine.

System suitability: reference solution (a):

- the chromatogram obtained is similar to the chromatogram supplied with chlorhexidine for performance test CRS in that the peaks due to impurity A and Impurity B precede that due to chlorhexidine; if necessary, adjust the concentration of acetic acid in the mobile ohase (increasing the concentration decreases the retention times)

Limits:

- totals: not more than the area of the principal peak in the chromatogram obtained with reference solution (b) (3.0 percent);

- disregard limit: the area of the principle peak in the chromatogram obtained with reference solution (c) (0.06 percent); disregard any peak with a relative retention time with reference to the principal peak of 0.25 or less