强化眼科抗生素的体外效力和稳定性。

In vitro potency and stability of fortified ophthalmic antibiotics.

作者信息

Arici M K, Sümer Z, Güler C, Elibol O, Saygi G, Cetinkaya S

机构信息

Department of Ophthalmology, Cumhuriyet University, School of Medicine, Sivas, Turkey.

出版信息

Aust N Z J Ophthalmol. 1999 Dec;27(6):426-30. doi: 10.1046/j.1440-1606.1999.00239.x.

DOI:10.1046/j.1440-1606.1999.00239.x

PMID:10641902

Abstract

PURPOSE

This study evaluates the in vitro potency, stability and contamination of the fortified ophthalmic antibiotic preparations of cefazolin, vancomycin, gentamicin and tobramycin stored for 4 weeks. The effects of the different solvents and storage temperatures on the antimicrobial potency and stability were also examined.

METHODS

The fortified stock solution of cefazolin and vancomycin were prepared by reconstituting with 0.9% sodium chloride and with artificial tears. Gentamicin and tobramycin were prepared by adding parenteral forms into their commercial ophthalmic solutions. The antimicrobial potency was measured by the minimum bactericidal concentration for cefazolin (33.3 mg/mL) and vancomycin (31 mg/mL) against Staphylococcus aureus, and for tobramycin (13.5 mg/mL) and gentamicin (13.5 mg/mL) against Pseudomonas aeruginosa. The stability of solution was evaluated by measuring absorbance spectra and pH. During the study period the levels of contamination of the stock solutions were examined by culturing on blood and on Sabouraud-dextrose media.

RESULTS

There were no differences in the antimicrobial potency of the cefazolin, vancomycin and tobramycin within the 4-week period; however, the potency of gentamicin was decreased at both temperatures after 21 days. It was found that different solvents or storage temperatures had no effect on the potency. Throughout the 4-week period, no change was found in the absorbance spectra of gentamicin and tobramycin, whereas the absorbance spectra of cefazolin and vancomycin stored at 24 degrees C increased in both of the solvents used (P<0.05). In all of the antibiotics, pH changed at 24 degrees C after 7-10 days; however, at 4 degrees C, only the pH of tobramycin exhibited changes after 14 days (P<0.05). No contamination was detected in the stock solutions during the study period.

CONCLUSION

Topical fortified antibiotic solutions used for longer than 7 days should be stored at < or =4 degrees C, those stored at 24 degrees C should be discarded after 7 days.

摘要

目的

本研究评估头孢唑林、万古霉素、庆大霉素和妥布霉素强化眼用抗生素制剂储存4周后的体外效价、稳定性及污染情况。还考察了不同溶剂和储存温度对抗菌效价及稳定性的影响。

方法

头孢唑林和万古霉素的强化储备液分别用0.9%氯化钠和人工泪液复溶配制。庆大霉素和妥布霉素则通过将注射用剂型加入其市售眼用溶液中配制。通过测定头孢唑林（33.3mg/mL）和万古霉素（31mg/mL）对金黄色葡萄球菌的最低杀菌浓度，以及妥布霉素（13.5mg/mL）和庆大霉素（13.5mg/mL）对铜绿假单胞菌的最低杀菌浓度来测定抗菌效价。通过测量吸收光谱和pH值评估溶液的稳定性。在研究期间，通过在血平板和沙氏葡萄糖培养基上培养来检测储备液的污染水平。

结果

头孢唑林、万古霉素和妥布霉素在4周内抗菌效价无差异；然而，21天后庆大霉素在两个温度下效价均降低。发现不同溶剂或储存温度对效价无影响。在整个4周期间，庆大霉素和妥布霉素的吸收光谱无变化，而在24℃储存的头孢唑林和万古霉素在两种所用溶剂中的吸收光谱均增加（P<0.05）。在所有抗生素中，24℃时7-10天后pH值发生变化；然而，在4℃时，仅妥布霉素的pH值在14天后出现变化（P<0.05）。研究期间储备液未检测到污染。