Determination of moisture content of povidone K30 by volumetric method

I. Preface

Povidone K30 (PVPK30) has extensive applications in medicine and is one of the three new pharmaceutical excipients advocated internationally. That is, according to the moisture determination method in the pharmacopoeia, Karl. The Fischer volumetric method was used for determination. Dissolve the sample with methanol and use Karl. Titration was carried out with Fischer titrant.

This method adopts Carl. The Fischer volumetric method for determining the moisture content has good repeatability and can accurately measure the moisture content.

Ii. Instruments and Reagents

2.1 Instruments

JH-V3 Karl Fischer moisture titrator (volumetric method), analytical balance, etc

2.2 Reagents

Karl Fischer titrant (Special reagent for aldehydes and ketones).

Iii. Experimental Methods

3.1 Sample Testing

Through the liquid discharge device of the moisture titrator, the residual liquid is removed. Then, 50mL of the special solvent for aldehyde-ketone is added to the titration cup, with the solvent covering the electrode. After setting the parameters, the instrument starts the pre-titration. When the instrument is in standby mode, click on the system injection, open the rubber stopper of the feeding port, add the sample with an appropriate amount of moisture to the titration cup, immediately cover the rubber stopper, and click Start measurement. Use Carl. Titrate the Fischer titrant to the endpoint, input the sample weight, and calculate the moisture content of the sample.

The parameters of the titrator are set as shown in Table 1:

Table 1 Titration Parameter Settings

Iv. Results and Discussion

4.1 Experimental Results

The experimental results are as shown in Table 2:

表 2 测试结果

4.2. Conclusion

The moisture content of povidone K30 tested this time is approximately 4.7%. The moisture content test results meet the moisture value required by the pharmacopoeia, indicating that the moisture content of this product complies with the pharmacopoeia standards. Moreover, the data repeatability is good, the detection efficiency is high, and at the same time, it can reduce the influence of the external environment on the test results. It is an excellent choice for detecting the moisture content of this type of product.

References

[1] Povidone K30[S], a pharmaceutical excipient, Chinese Pharmacopoeia 2020 Edition, Part IV