Quantitative analysis of related substances in polyvinyl alcohol eye drops using HPLC-UV

doi:10.5246/jcps.2025.05.033

Abstract

Abstract:

The current quality standard for polyvinyl alcohol eye drops lacks an impurity assessment, despite the potential impact of raw material impurities on product safety. To strengthen quality control and ensure drug safety, an investigation into the impurity profile of the formulation was conducted, and an HPLC-UV method was developed for impurity quantification. The method validation was performed using an H-type cation exchange column. A total of 116 batches of polyvinyl alcohol eye drops from four manufacturers and two batches of the innovator drug were analyzed. Formic acid was detected exclusively in 0.4 mL samples from Company A and the innovator drug, with concentrations below 0.002% in both cases. Acetic acid was identified in samples from all manufacturers, with levels not exceeding 0.1%. The method demonstrated high specificity and sensitivity, making it well-suited for the quantification of formic and acetic acids in polyvinyl alcohol eye drops. The presence of formic acid was attributed to excipients, whereas acetic acid originated from raw materials and was further generated during pH adjustment in manufacturing. Although the overall impurity levels were low and posed minimal risk to drug safety, manufacturers should remain vigilant regarding impurity control to maintain product quality.

Key words: Polyvinyl alcohol eye drops, Related substances, Formic acid, Acetic acid

Supporting:

Yongfei Li, Wenfen Gao, Jihua Liu, Zheyuan Li, Zhiyuan Li. Quantitative analysis of related substances in polyvinyl alcohol eye drops using HPLC-UV[J]. Journal of Chinese Pharmaceutical Sciences, 2025, 34(5): 432-442.

Figures/Tables 14

Table 1. Linear relationship of formic acid and acetic acid impurities.

Table 2. Results of the repeatability test.

Table 3. Results of the recovery test.

Table 4. Results of solution stability determination.

Table 5. Statistical table of the determination results of formic acid and acetic acid.

Table 6. Results of the polyvinyl alcohol destructive test.

Table 7. Results of the study on the relationship between acetic acid content and pH stability in polyvinyl alcohol eye drops (in past tense).

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