Research on the relationship between cephalosporin structure, solution clarity, and rubber closure compatibility using volatile components profile of butyl rubber closures.

OBJECTIVE: Establish an effective experimental strategy to determine the compatibility of rubber closures for drugs. SIGNIFICANCE: Various types of rubber closures with different compositions are available for drug packaging. Many additives of rubber closures can be released from rubber closures and may affect the quality of drugs and pose a risk to human health. In this study, we aimed to determine the relationship between cephalosporin structure, solution clarity, and rubber closure compatibility using volatile components profile of butyl rubber closures. METHODS: Two opposite polarity gas chromatography (GC) systems and GC-mass spectrometry (MS) were used to achieve rapid qualitative determination of the main volatile components in rubber closures. Simulated adsorption experiment was performed to investigate the adsorption of main volatile components in rubber closures by cephalosporins with different side chain structures, and to determine the effects of adsorption on solution clarity. RESULTS: A volatile components screening library of rubber closures was established and the structures of some volatile component were confirmed. The specific adsorption of the structure of cephalosporins on volatile components from rubber closures was studied. CONCLUSION: Based on the results of this study, rubber closures with good compatibility for cephalosporins with different side chain structures can be selected rapidly. This experimental strategy not only facilitates the screening of suitable rubber closures more effectively, but also enables the quick determination of volatile components adsorbed by drugs.

Rapid Analysis of the Quality of Amoxicillin and Clavulanate Potassium Tablets Using Diffuse Reflectance Near-Infrared Spectroscopy.

The cycle-closed dimer of amoxicillin influences its critical quality and is an important impurity in amoxicillin and clavulanate potassium tablets. The quality of the tablets could be rapidly evaluated using the impurity as an indicator. Here, we report a quantitative model to determine the cycle-closed dimer in samples from different manufacturers using diffuse reflectance near-infrared (NIR) spectroscopy by partial least squares regression for one y variable (PLS1) and hierarchical cluster analysis. Because the contents of the (active pharmaceutical ingredients) APIs (amoxicillin and clavulanate potassium) and water are also the important indexes of the tablet quality, three other quantitative models were used to confirm the API data and water content. All of the four models facilitate rapid and complete control of the tablet quality. In addition, quantitative models were validated in terms of specificity, linearity, accuracy, repeatability, and intermediate precision according to the International Conference on Harmonisation guidelines by evaluating the characteristics of the NIR spectra. These results confirmed that the models were satisfactory.

[The control of the critical quality attributes of amoxicillin and clavulanate potassium tablet].

The critical attribute was analyzed in clavulanate potassium tablet of amoxicillin according to the principle QbD. By investigation of the drug impurity profile, the cycle-closed dimer and penicilloic acid of amoxicillin were considered to be the critical impurities, and the sources and the degradation pathways of these two impurities were discussed. The research confirmed that crystal form was the critical attribute of drug substance. The drying process in the tablet granulation was regarded as the critical process parameter. The tablet formulation was also another factor in the impurity generation. This study provides a new idea for the evaluation of drug quality.

Simultaneous determination of purity and potency of the components of gentamycin using high-performance liquid chromatography.

The quality of some earlier developed antibiotics is usually ensured by the combination of HPLC purity and microbiological potency measurement in the pharmacopoeias of various countries because the relationship between their purity and potency is not clearly quantified. Due to potency is assessed using certain units of measurement, it can not be directly traced to the international system of units (SI unit). This has become a hotspot in the study of the quantitative relationship between purity and potency of antibiotics. It would be quite an achievement to simultaneously determine both purity and potency using HPLC methods during quality control. This study evaluated a multicomponent antibiotic product, gentamycin, as a test sample. First, pure samples of the C components of gentamycin: C1a, C2, C2a and C1 were prepared, separately. Second, quantitative relationship (theoretical potency) between the purity and potency of each C component of gentamycin were determined using 1H NMR, HPLC-ELSD and microbiological assay method. One milligram of gentamycin C1a, C2, C2a and C1 was equal to 1 286.98, 1 095.74, 1 079.52 and 739.61 gentamycin units, respectively. Finally, a method for the determination of gentamycin potency was established based on the proportion and content of C components of gentamycin. The unification of purity and potency for gentamycin was achieved using only HPLC-ELSD. It is also demonstrated that C components of gentamycin and micronomicin produce the same responses under ELSD, which means that it is not necessary to prepare separate reference standards for each C component of gentamycin and that quantitative testing can be performed accurately using only one micronomicin reference standard. This study simplified the previous method for the determination of the content of C components of gentamycin using HPLC-ELSD. The developed method is suitable for regular use as a part of quality control and can simplify the rigmarole quality control procedures provided in current pharmacopeias.

Study on Isomeric Impurities in Cefotiam Hydrochloride.

In this study, two isomeric impurities were identified in cefotiam hydrochloride injection preparation and were characterized. Column-switching HPLC-MS and NMR techniques were used to identify the impurity 1 as the Δ3(4) isomers of cefotiam. Using software-based calculations, it was predicted that neither of the isomeric impurities was embryotoxic. This study provides a reference for the production, storage, and quality control of cefotiam and related cephalosporin antibiotics.

Exploring quality and its potential effects of multi-components antibiotic: consistency evaluation between matrix components ratio and microbiological potency of teicoplanin.

The production process, such as fermentation and purification etc., can significantly affect the relative ratio of matrix components in a multi-component antibiotic. The ratio of components can be varied in different products. This status causes a difficulty to assure the homogeneity and consistency between reference standards and test samples in potency determination, which hinders the results judgment and accuracy of a routine microbiological assay. In the current study, a multi-component antibiotic, teicoplanin, was selected as a model to explore the relationship between the ratio of matrix component and antibiotics potency. Single-component samples, TA3-1, TA2-1, and mixed-component samples, TA2-2.3, TA2-4.5, of teicoplanin were prepared and purified. Dose-response relationship of each sample has been determined by HPLC and microbiological assay, respectively. The accuracy of the potency result was guaranteed by choosing a test organism with the same sensitivity to each component of teicoplanin when there were differences existing in the ratio of components between the reference standard and the test sample. The experimental methods in current specifications can be replaced with the new potency determination method, which can provide a more realistic reflection of the biological activity of the product.