Method for separating carbamazepine and its related substances through liquid chromatography

[0104] Experimental Example 1: Verification of Chromatographic Conditions in Pharmacopoeia

[0105] According to the chromatographic conditions stipulated in the Chinese Pharmacopoeia, a system adaptability experiment was carried out on carbamazepine, and the carbamazepine sample used was produced by our company with batch number 2017021303. The specific chromatographic conditions are as follows:

[0106] (1) Chromatographic conditions

[0107]

[0108] (2) Sample preparation

[0109]

[0110]

[0111] (3) See the results figure 1 . The separation of carbamazepine and impurity A, impurity B, impurity C, impurity D and impurity E is as follows.

[0112] name

keep time

area

Number of theoretical plates

Separation

S / N (Signal to Noise Ratio)

Impurity B

9.153

439898

3861

58.06

Impurity A

12.379

162994

3594

4.70

15.93

carbamazepine

14.193

8501116

3802

2.13

725.00

Impuri...

[0132] Embodiment 1: the exploratory test of carbamazepine related substance detection condition

[0133] 1. First, change the mobile phase system. There is tetrahydrofuran in the mobile phase system, which has absorption at low wavelengths, which may cover up the impurity peaks, and adopt the acetonitrile-water gradient elution method. The new chromatographic conditions are as follows:

[0134] (1) Chromatographic conditions

[0135]

[0136] (2) See the attached chromatogram for the results Figure 5 . Carbamazepine and the separation of impurities are as follows:

[0137]

[0138] (3) Conclusion

[0139] The concentration of each impurity in carbamazepine was about 9 μg / mL, one impurity in carbamazepine did not appear as a peak, and the other impurities were well separated. Reason analysis: In addition to removing tetrahydrofuran from the mobile phase, triethylamine was removed at the same time, and the impurity of carbamazepine contains N, so there is no peak. ...

[0200] Embodiment 2 Destructive test

[0201] 1 Acid, alkali and oxidation damage (sample group: 2017032801)

[0202] 1.1 Undestroyed API

[0203] Take 75 mg of carbamazepine raw material, accurately weigh it, put it in a 50 ml measuring bottle, add 25 ml of methanol to dissolve, ultrasonically dissolve, add water to dilute to the mark, shake well, and obtain. Measure 5.00ml of the solution in a 50ml volumetric flask, add 22ml of methanol, dilute with water to the mark, and shake well to obtain.

[0204] see attached results Figure 17 :

[0205] name

keep time

peak name

Purity angle

Purity Threshold

area

area%

Separation

s / n

1

21.338

main peak

0.232

0.345

52876503

100

12862.92

[0206] 1.2 Acid Destruction

[0207] Acid-base blank: Pipette 5.00ml of 1mol / L hydrochloric acid solution and sodium hydroxide solution into a 50ml volumetric flask, add 25ml of methanol solution, dilute with water to t...