临时配制的万古霉素及头孢他啶滴眼液稳定性和体外抗菌活性研究

Stability and antibacterial activity in vitro of temporary preparation ceftazidime and vancomycin eyedrops

目的研究临时配制的万古霉素和头孢他啶滴眼液在不同温度和光照下的稳定性和体外抗菌活性。方法平衡盐溶液制备头孢他啶滴眼液(50 mg/m L)和万古霉素滴眼液(50 mg/m L)。2种滴眼液在光照及避光条件下,分别保存于4℃及24℃,分别观察其在0、3、7、14、21和28d的物理性质和p H值变化,并评价万古霉素对金黄色葡萄球菌和头孢他啶滴眼液对铜绿假单胞菌的最低杀菌浓度。结果保存于24℃和4℃的头孢他啶滴眼液抗菌活性分别从第3天和第7天起显著下降,并且与光照与否无关。溶液p H由弱酸性转变为弱碱性,于第3天p H达到峰值。万古霉素滴眼液的抗菌活性在4周内保持稳定,但溶液p H值升高表明其酸性降低。结论头孢他啶平衡盐溶液在4℃时抗铜绿假单胞菌活性可维持7 d以上,但保存于24℃时则显著下降。从头孢他啶溶液的颜色及其物理性质变化可观察其降解,p H在第3天突然升高需引起重视。万古霉素平衡盐溶液在4℃或24℃均可保存4周以上。

Objective To study the stability and antibacterial activity in vitro of temporary preparation ceftazidime and vancomycin eyedrops respectively under different storage temperatures and light conditions.Methods Solutions of ceftazidime 50 mg/mL and vancomycin 50 mg/mL were prepared by reconstituting with balanced salt solution （ BSS） and stored at 4℃ and 24℃with and without exposure to light, respectively.Changes in pH values and physical characteristics of the solutions were recorded and minimum bactericidal concentrations against P.aeruginosa and S.aureus were measured at 0, 3, 7, 14, 21 and 28d respectively.Results The antibacterial potency of ceftazidime decreased significantly from days 3 and 7 at storage temperatures of 24℃ and 4℃, respectively, but was not affected by light exposure.The pH value progressed from acidic to alkaline, reached maxium value at 3 day, in all solutions.The antibacterial potency of vancomycin remained stable during the four-week period, but its pH increased showed that acidity decreased.Conclusion Ceftazidime eyedrops in BSS appears to remain effective against P.aeruginosa 7 days above when stored at 4℃, but are less effective when stored at 24℃.The degradation was observed using the color changes of ceftazidime solution and its physical properties, which should be pay attention to the suddenly rise in the 3rd day, however, as it may affect patients’tolerance.Vancomycin eyedrops in BSS can be safely used for 4 weeks above, stored at either 4℃ or 24℃.