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- van der Burg, Debbie, et al.
(författare)
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Analysis of Cationic Vitamins in Cell Culture Medium Samples by Capillary Zone Electrophoresis
- 2022
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Ingår i: Journal of Analytical Methods in Chemistry. - : Hindawi Limited. - 2090-8865 .- 2090-8873. ; 2022, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes a capillary electrophoresis method for the determination of the cationic B-vitamins thiamine, nicotinamide, pyridoxine, pyridoxal, and pyridoxamine in untreated cell culture medium samples. The effects of the buffering capacity, the mobility of the coion, and the preconditioning solution on the robustness of the method were investigated. Using a 100 mM phosphoric acid and 55 mM triethanolamine background electrolyte at pH 2.3 and capillary preconditioning with 1 M NaOH, all five vitamins could be separated with good resolution. Preliminary method validation data over the range 10-110 mu M for undiluted samples, with 10 mu M being the lower range limit of quantification QL, showed accuracy recoveries of 94-104%, and migration time and peak area repeatabilities within 0.4% RSD and 2.6% RSD, respectively.
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| 2. |
- Wiesner, Rebecca, et al.
(författare)
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An interlaboratory capillary zone electrophoresis-UV study of various monoclonal antibodies, instruments, and ε-aminocaproic acid lots
- 2023
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Ingår i: Electrophoresis. - : Wiley. - 0173-0835 .- 1522-2683. ; 44:15-16, s. 1247-1257
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Tidskriftsartikel (refereegranskat)abstract
- Capillary zone electrophoresis ultraviolet (CZE-UV) has become increasingly popular for the charge heterogeneity determination of mAbs and vaccines. The ε-aminocaproic acid (eACA) CZE-UV method has been used as a rapid platform method. However, in the last years, several issues have been observed, for example, loss in electrophoretic resolution or baseline drifts. Evaluating the role of eACA on the reported issues, various laboratories were requested to provide their routinely used eACA CZE-UV methods, and background electrolyte compositions. Although every laboratory claimed to use the He et al. eACA CZE-UV method, most methods actually deviate from He's. Subsequently, a detailed interlaboratory study was designed wherein two commercially available mAbs (Waters’ Mass Check Standard mAb [pI 7] and NISTmAb [pI 9]) were provided to each laboratory, along with two detailed eACA CZE-UV protocols for a short-end, high-speed, and a long-end, high-resolution method. Ten laboratories participated each using their own instruments, and commodities, showing excellence method performance (relative standard deviations [RSDs] of percent time-corrected main peak areas from 0.2% to 1.9%, and RSDs of migration times from 0.7% to 1.8% [n = 50 per laboratory], analysis times in some cases as short as 2.5 min). This study clarified that eACA is not the main reason for the abovementioned variations.
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| 3. |
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| 4. |
- van der Burg, Debbie, et al.
(författare)
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Recent capillary electrophoresis applications for upstream and downstream biopharmaceutical process monitoring
- 2023
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Ingår i: TrAC. Trends in analytical chemistry. - : Elsevier BV. - 0165-9936 .- 1879-3142. ; 160
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Forskningsöversikt (refereegranskat)abstract
- The biopharmaceutical market is one of the fastest growing biotechnology markets. In order to ensure affordable and reliable therapeutics, the biopharmaceutical process has to be closely monitored. Capillary electrophoresis (CE) has proven to be a valuable technique for the analysis of product concentration, critical quality attributes, product and process-related impurities, and nutrients and metabolites in the cell culture medium. Capillary zone electrophoresis, capillary gel electrophoresis, and capillary isoelectric focusing are extensively used for product concentration, and size or charge heterogeneity determination. CE has a number of benefits for the analysis of upstream and downstream process-intermediates, including the ability to handle highly complex matrices found in process-intermediates, high resolving power, little sample preparation requirements, rapid analysis, and low solvent and sample consumption. The small sample volumes (nL range) are especially beneficial for microbioreactor analysis or clone se-lection experiments. The simple setup and the possibility for miniaturisation and automation using microchip CE provides great opportunities for on-site, real-time monitoring of the process. This review discusses CE applications in upstream and downstream processing of the last decade.
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