\ According to the analysis of the residual products by thermogravimetric analysis (TGA), the thermal decomposition process of cefazolin sodium (CEZ·Na) was thought to be similar to the degradation in solid sta...\ According to the analysis of the residual products by thermogravimetric analysis (TGA), the thermal decomposition process of cefazolin sodium (CEZ·Na) was thought to be similar to the degradation in solid state in its storage time. This laid a foundation for estimating the relative chemical stability of the drug by determination of its decomposition kinetics using TGA. Although the observed thermal decomposition kinetics of CEZ·Na was complex, a conversion level of 1% was chosen for evaluation of the stability of CEZ·Na crystalline since the mechanism here was more likely to be that of the actual product failure. The evaluation results suggested that the α form of CEZ·Na had the best stability and the amorphous one was the least stable one among α form, dehydrated α form and amorphous form.展开更多
A sensitive and specific high performance liquid chromatography method was established for measuring cefazolin sodium level in rabbit synovial fluid. Acetonitrile was used to precipitate proteins and antipyrine was us...A sensitive and specific high performance liquid chromatography method was established for measuring cefazolin sodium level in rabbit synovial fluid. Acetonitrile was used to precipitate proteins and antipyrine was used as internal standard. Samples were analyzed on a Dionex Ultimate U3000 HPLC system equipped with Phenomenex Luna C18 column (150 mmx4.60 mm, 5 Bm, 100 A). The mobile phase consisted of acetonitrile and 0.1% formic acid in water. The flow rate was 1 mL/min. The detection wavelength was set at 272 nm. The column temperature was maintained at 25 ℃. The calibration curve was linear in the range of 1.0-100.0 μg/mL (r2 = 0.9999). The limit of detection (LOD, S/N - 3) was 0.07 μg/mL. The limit of quantitation (LOD, S/N = 10) was 0.22 pg/mL. The recovery of cefazolin sodium (low, medium and high) was 124.6%, 117.8%, and 100.6% (RSD% - 1.9%, 4.0%, 1.1%, n = 5), respectively. The intra-day and inter-day precision values were in the range of 0.5%-2.7%. The method was simple, sensitive and reliable. It can be used for the quantitative determination of cefazolin sodium in rabbit synovial fluid.展开更多
Objective: To explore the possibility of repairi ng long segmental bone defects and preventing infection with cefazolin loaded bo ne matrix gelatin (C-BMG).Methods: C-BMG was made from putting cefazolin into BMG by va...Objective: To explore the possibility of repairi ng long segmental bone defects and preventing infection with cefazolin loaded bo ne matrix gelatin (C-BMG).Methods: C-BMG was made from putting cefazolin into BMG by vac uum absorption and lyophilization techniques. The sustaining period of effective drug concentration in vitro and in vivo was detected. The time of inhibiting ba cteria,and the drug concentration in local tissues (bone and muscle) and plasma after implantation of C-BMG were examined by high performance liquid chromatog raphy. Results: The effective inhibition time to staphylococcus aureus of C-BMG was 22 days in vitro; while 14 days in vivo. The cefazolin concentrat ion in local tissues was higher in early stage,and later it kept a stable and l ow drug release. C-BMG showed an excellent ability to repair segmental long bon e defects.Conclusions: C-BMG can gradually release cefazolin with effect ive drug concentration and has excellent ability to repair segmental bone defect s. It can be used to repair segmental long bone defects and prevent infection af ter operation.展开更多
Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have diff...Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have different physical and chemical properties, it is critical to emphasize the crystallization control of polymorphic medicines. Near-infrared (NIR) analysis, which incorporates a combination of NIR spectroscopic techniques and multivariate chemometric methods, is considered a powerful tool for the determination of the crystallinity of polymorphic drugs. The selection of optimal spectral ranges that correlate with the lattice specificity and content specificity is crucial to obtaining a specific NIR model. In the present work, near-infrared (NIR) spectra of cefazolin sodium with different crystal forms created through different processes were studied. The results suggest that wavelengths within the range of 9102.7-8597.5 cm-1 is related to the specificity of the cefazolin sodium crystal lattice and that the range of 6001.6-5496.4 cm i is associated with the quantitative content of cefazolin sodium. The two ab- sorptions are caused by the second overtone of the C-H stretching band (3nC-H) and the first overtone of C-H stretching band (2uC-H), respectively. Using these results, we established a suitable method of constructing a universal quantitative model by using mixed samples in different crystal forms as a calibration set, selecting a content-specific range (6001.6-5496.4 cm-l), and adding lattice-related spectral ranges where appropriate. This may provide a framework for the construction of prediction models for polymorphic medicines.展开更多
文摘\ According to the analysis of the residual products by thermogravimetric analysis (TGA), the thermal decomposition process of cefazolin sodium (CEZ·Na) was thought to be similar to the degradation in solid state in its storage time. This laid a foundation for estimating the relative chemical stability of the drug by determination of its decomposition kinetics using TGA. Although the observed thermal decomposition kinetics of CEZ·Na was complex, a conversion level of 1% was chosen for evaluation of the stability of CEZ·Na crystalline since the mechanism here was more likely to be that of the actual product failure. The evaluation results suggested that the α form of CEZ·Na had the best stability and the amorphous one was the least stable one among α form, dehydrated α form and amorphous form.
基金National Natural Science Foundation(Grant No.81373372)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20110001110021 and 20130001110059)
文摘A sensitive and specific high performance liquid chromatography method was established for measuring cefazolin sodium level in rabbit synovial fluid. Acetonitrile was used to precipitate proteins and antipyrine was used as internal standard. Samples were analyzed on a Dionex Ultimate U3000 HPLC system equipped with Phenomenex Luna C18 column (150 mmx4.60 mm, 5 Bm, 100 A). The mobile phase consisted of acetonitrile and 0.1% formic acid in water. The flow rate was 1 mL/min. The detection wavelength was set at 272 nm. The column temperature was maintained at 25 ℃. The calibration curve was linear in the range of 1.0-100.0 μg/mL (r2 = 0.9999). The limit of detection (LOD, S/N - 3) was 0.07 μg/mL. The limit of quantitation (LOD, S/N = 10) was 0.22 pg/mL. The recovery of cefazolin sodium (low, medium and high) was 124.6%, 117.8%, and 100.6% (RSD% - 1.9%, 4.0%, 1.1%, n = 5), respectively. The intra-day and inter-day precision values were in the range of 0.5%-2.7%. The method was simple, sensitive and reliable. It can be used for the quantitative determination of cefazolin sodium in rabbit synovial fluid.
基金ThisprojectwassupportedbyagrantfromtheMinistryofHealth (No .96 1 14 5 )
文摘Objective: To explore the possibility of repairi ng long segmental bone defects and preventing infection with cefazolin loaded bo ne matrix gelatin (C-BMG).Methods: C-BMG was made from putting cefazolin into BMG by vac uum absorption and lyophilization techniques. The sustaining period of effective drug concentration in vitro and in vivo was detected. The time of inhibiting ba cteria,and the drug concentration in local tissues (bone and muscle) and plasma after implantation of C-BMG were examined by high performance liquid chromatog raphy. Results: The effective inhibition time to staphylococcus aureus of C-BMG was 22 days in vitro; while 14 days in vivo. The cefazolin concentrat ion in local tissues was higher in early stage,and later it kept a stable and l ow drug release. C-BMG showed an excellent ability to repair segmental long bon e defects.Conclusions: C-BMG can gradually release cefazolin with effect ive drug concentration and has excellent ability to repair segmental bone defect s. It can be used to repair segmental long bone defects and prevent infection af ter operation.
基金the National Key New Drug R&D Program Foundation of China (2010ZX09401-403) for the financial support
文摘Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have different physical and chemical properties, it is critical to emphasize the crystallization control of polymorphic medicines. Near-infrared (NIR) analysis, which incorporates a combination of NIR spectroscopic techniques and multivariate chemometric methods, is considered a powerful tool for the determination of the crystallinity of polymorphic drugs. The selection of optimal spectral ranges that correlate with the lattice specificity and content specificity is crucial to obtaining a specific NIR model. In the present work, near-infrared (NIR) spectra of cefazolin sodium with different crystal forms created through different processes were studied. The results suggest that wavelengths within the range of 9102.7-8597.5 cm-1 is related to the specificity of the cefazolin sodium crystal lattice and that the range of 6001.6-5496.4 cm i is associated with the quantitative content of cefazolin sodium. The two ab- sorptions are caused by the second overtone of the C-H stretching band (3nC-H) and the first overtone of C-H stretching band (2uC-H), respectively. Using these results, we established a suitable method of constructing a universal quantitative model by using mixed samples in different crystal forms as a calibration set, selecting a content-specific range (6001.6-5496.4 cm-l), and adding lattice-related spectral ranges where appropriate. This may provide a framework for the construction of prediction models for polymorphic medicines.