Bupivacaine was found to be unstable during the accelerated storage condition(40 ℃ and 75% relative humidity), and two degradation impurities with the same protonated molecular ion were observed by high performance liquid chromatography-mass spectrometry (LC-MS). A semipreparative method was used to separate and purify the two impurities, and their structures were elucidated via comprehensive HR-MSMS and NMR spectroscopy analyses. Their stereo structures were characterized through single crystal X-ray diffraction. Meanwhile, an LC-MS method was developed and validated to quantify the two degradation impurities of bupivacaine. Chromatographic separation was performed on a C18 reversed-phase column (4.6 × 150 mm, 5 µm) using an equivalent elution with water and methanol. The limits of quantitation for the two degradation impurities (named RS1 and RS2) were 0.89 and 0.65 ng, respectively, and the average recoveries were in the range of 90∼108% and relative standard deviations were less than 5.0%. The proposed LC-MS method can be used to control the quality of bupivacaine and its formulations. DATA AVAILABILITY: Data will be made available on request.
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http://dx.doi.org/10.1016/j.jpba.2023.115236 | DOI Listing |
J Am Chem Soc
January 2025
Nanoyang Group, Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage, School of Chemical Engineering and Technology, National Industry-Education Integration Platform of Energy Storage, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, China.
In situ polymerization strategies hold great promise for enhancing the physical interfacial stability in solid-state batteries, yet (electro)chemical degradation of polymerized interfaces, especially at high voltages, remains a critical challenge. Herein, we find interphase engineering is crucial for the polymerization process and polymer stability and pioneer an in situ polymerization-fluorination (Poly-FR) strategy to create durable interfaces with excellent physical and (electro)chemical stabilities, achieved by designing a bifunctional initiator for both polymerization and on-surface lithium donor reactions. The integrated in situ fluorination converts LiCO impurities on LiNiCoMnO (NCM811) surfaces into LiF-rich interphases, effectively inhibiting the aggressive (de)lithiation intermediates and protecting the interface from underlying chemical degradation, thereby surpassing the stability limitations of polymerization alone.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
School of Chinese Medicine, Hong Kong Baptist University, 999077, Hong Kong. Electronic address:
Natural polysaccharides attract scientists and industries' interest with diverse applications in biomaterials, immune regulation, gut microbiota regulation, food additives, and more. Nevertheless, the absence of standardized purity criteria created significant challenges in characterizing polysaccharides, leading to varied and complicated structures, and impeding progress in research and development. Consequently, it is essential to obtain samples that adhere to high-level and unified purity standards for effective polysaccharide research.
View Article and Find Full Text PDFOrg Process Res Dev
January 2025
Department of Chemical Engineering, University of Chemistry and Technology, Technická 3, Prague 6, Dejvice 166 28, Czech Republic.
The choice of method for drug amorphization depends on various factors, including the physicochemical properties of the active pharmaceutical ingredients, the desired formulation, and scalability requirements. It is often important to consider a combination of methods or the use of excipients to further enhance the stability and performance of the amorphous drug. This study presents a comparison of techniques including melt quench, hot melt extrusion, solvent evaporation, ball milling, and lyophilization used for the preparation of amorphous ibrutinib.
View Article and Find Full Text PDFBiotechnol J
January 2025
Biologics Process Research & Development, Merck & Co., Inc., Rahway, New Jersey, USA.
Chinese hamster ovary (CHO) cells are widely used to produce recombinant proteins, including monoclonal antibodies (mAbs), through various process modes. While fed-batch (FB) processes have been the standard, a shift toward high-density perfusion processes is being driven by increased productivity, flexible facility footprints, and lower costs. Ensuring the clearance of process-related impurities, such as host cell proteins (HCPs), is crucial in biologics manufacturing.
View Article and Find Full Text PDFJ Pharm Sci
January 2025
Formulation and Drug Product Development, Biologics, Dr. Reddy's Laboratories, Hyderabad, India. Electronic address:
Formulation robustness study was performed for a biosimilar monoclonal antibody (IgG1) manufactured at Dr. Reddy's Laboratory, where the pH and concentration level of excipients in the drug product formulation were systematically varied from the target formulation. It was observed that the IgG1 formulation having relatively low pH and high citrate (buffer salt) concentration were predisposed to the formation of low molecular weight impurities.
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