ABSTRACT
OBJECTIVE: To study the stability of dexamethasone sodium phosphate(DSP) eye drops and predict its validity duration.METHODS: The content of DSP in eye drops was determined by HPLC and its validity duration was predi-cated using initial average rate method.RESULTS: The linear concentration range of DSP was 18～70 ?g?mL-1(r=0.999 9) with an average recovery rate of 99.74%(RSD=0.37%).The content of DSP in the eye drops decreased as its storing temperature increased and the storing time prolonged,but its pH was stable. The validity duration of the eye drops was computed to be 70 days at 25 ℃ and 438 days at 4 ℃.CONCLUSION: This eye drops were stable at 4 ℃.
ABSTRACT
OBJECTIVE:To study the stability of timolol maleate eye drops and predict its storage period at room temperature METHODS:Timolol maleate was determined by UV-spectrophotometry,initial average rate method was used in predicting the expiry term RESULTS:Stability of the 0 5% timolol maleate eye drops was not so good,expiry term predicted at 25℃ was only 70 days,while at 5℃ was as long as 1 2 years CONCLUSIONS:Initial average rate method is rapid,convenient and precise,so it is suitable for stability study of hospital preparations
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OBJECTIVE:To study the stability of Aloe gel under conditions of high and low temperature, high humidity and high light and to predicate its validity duration stored under room temperature. METHODS: The content of Polysaccharide in the gel was determined by phenol-sulfuric acid method. Aloe gel was put under the conditions of high temperature, low temperature, high-relative humidity, and high light to investigate the changes in appearance, pH and content. The expiry term of Aloe gel was predicted by initial average rate method. RESULTS: The content was highly correlated to temperature, but it had little correlation with light and humidity. The validity duration for Aloe gel at room temperature (25 ℃) is expected to be 1 year. CONCLUSION: Aloe gel should be cool-stored under room temperature.
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OBJECTIVE:To observe the stability of phacolin eye drops.METHODS:The content and the stability of phacolin eye drops were determined by ultraviolet spectrophotometry and the initial average rate method respectively.RESULTS:The activation energy for pyrolytic reaction of phcolin eye drops was25.681kcal/mol,the shelflife of phacolin eye drops at room temperature(25℃)and10℃were88and878days respectively.CONCLUSION:The determination of the stability of phacolin eye drops with initial average rate method is useful and simple.