August 30th 2024
Here is some of the most popular content posted on LCGC International this week.
The 2022 Winners of the Lifetime Achievement and Emerging Leader in Chromatography Awards
February 1st 2022Barry L. Karger and James P. Grinias are the winners of the 15th annual LCGC Lifetime Achievement and Emerging Leader in Chromatography Awards, respectively, for 2022. Here, we review their achievements.
Rapid Adeno-Associated Virus Genome Integrity Analysis by Capillary Gel Electrophoresis
October 9th 2020In this paper, two adeno-associated virus (AAV) genome integrity analysis workflows are introduced; a standard sample preparation protocol and an accelerated procedure, both utilizing capillary gel electrophoresis with laser induced fluorescent detection (CGE–LIF) to analyze the released nucleic acids.
Chromatographic Innovations for Cell Therapies
July 7th 2020The complexity and challenges of developing, manufacturing, and controlling cell therapies offer today’s chromatographic scientists new opportunities to join the journey of discovery and innovation needed to develop and commercialize this new drug modality. This article explores the latest developments and highlights the importance of new capillary electrophoresis–mass spectrometry (CE–MS)-based approaches to understand the efficiency of cell therapy production.
Capillary Electrophoresis: The Past, Present, and Future
November 1st 2017Inspired by the work of Jorgenson and Lukacs, 30 years ago, the group of Richard Smith at Pacific Northwest National Laboratory in Washington (USA) reported the first online coupling of the microscale separation technique capillary electrophoresis (CE) to electrospray ionization (ESI) mass spectrometry (MS) using a sheath-liquid interface.
Affinity Capillary Electrophoresis— A Powerful Tool to Investigate Biomolecular Interactions
May 1st 2017In the biomedical research of molecular bases of both normal and pathological biological processes, it is currently necessary not only to detect, identify, and quantify individual compounds, but also to study their interactions with endo- and exogenous compounds. Obviously, for these purposes it is crucial to develop new advanced high‑performance analytical methods providing high sensitivity, high selectivity, and high throughput. These challenging requirements are well met by capillary electromigration (CE) methods. They have developed in the last three and half decades into high‑performance separation techniques suitable for the analysis of a wide spectrum of both low- and high‑molecular mass bioactive compounds.
Separation of Amino Acid Enantiomers Using Capillary Electrophoresis with a New Chiral Ligand
April 1st 2016A chiral ionic liquid, namely 1-ethyl-3-methyl imidazole L-tartrate ([EMIM][L-Tar]), was applied as a new chiral ligand for the enantioseparation of tryptophan, tyrosine, and phenylalanine enantiomers by chiral ligand exchange CE. To validate the unique behavior of [EMIM][L-Tar], the performance of L-tartaric acid and 1-ethyl-3-methyl imidazole L-proline as chiral ligands was investigated to make a comparison with [EMIM][L-Tar]. Then the separation mechanism was further discussed. It was proven that [EMIM][L-Tar] was a good chiral ligand and would have good application prospects in separation science.
An analytical methodology for the characterization of the primary structure of biotherapeutic proteins using sheathless CE–ESI-MS-MS instrumentation is presented. For the first time, complete sequence coverage can be achieved using a bottom-up proteomic approach from a single analysis of a tryptic digest. In a biosimilarity assessment, a single amino acid substitution was detected.
Multiple-Injection Affinity Capillary Electrophoresis
August 12th 2009October 2006. The authors demonstrate the use of multiple-injection affinity capillary electrophoresis (MIACE) and several variations to MIACE to determine binding constants between the glycopeptide antibotics vancomycin, ristocetin, and teicoplanin from Streptomyces orientalis, Nocardia lurida, and Actinoplanes teichomyceticus, respectively, and D-Ala-D-Ala terminus peptides.
Molecular Interaction Sensors: A New Type of Detector for Separation Methods
Potentiometry is a new detection method for liquid chromatography (LC) and capillary electrophoresis (CE). The principle behind this method is familiar to chromatographers because the signals depend on the partitioning tendency of analytes over the sensor coating and the eluent. This partitioning provokes a change in the surface potential and the detection of these changes can be classified as "potentiometric". A conversion algorithm is needed to convert the generated signals to concentration-related tracings (chromatograms).
CE–MS-MS for the Identification of Chemical Warfare Agent Degradation Products
March 1st 2007With the threat of terrorism growing, the development of analytical techniques for the detection and identification of chemical warfare agent defradation products has increased. Capillary electrophoresis (CE) presents interesting features for this application.
Capillary Electrophoresis in the Biopharmaceutical Industry: Part I
July 1st 2005Almost 40 years have passed since the concept of capillary electrophoresis (CE) was described by Hjertén (1) in 1967. It emerged as a viable analytical technique after the pioneering work of Jorgenson (2) in the early 1980s, and commercial instruments were first introduced at the end of that decade. It is appropriate at this time to survey the history of CE and to judge its success in the world of analytical instrumentation.
Planar Chromatography Versus Column Chromatography: A Performance Comparison
March 1st 2005It is hypothesized that in particular cases, conventional planar chromatography provides a more effective and robust system than column chromatography with regard to separation efficiency and peak distribution of mixtures composed of low-retarded analytes. Under similar reversed-phase experimental conditions, a regular distribution of thin-layer chromatography (TLC) spots of four natural estrogens (estetrol, estriol, 17?-estradiol, and estrone) corresponds to strong irregular dispersion of peaks in chromatograms generated by high performance liquid chromatography. In both cases, the efficiency of separation was assessed using simple optimization criteria such as selectivity (?min) and resolution (Rs min). The distribution of chromatographic spots was evaluated using the relative resolution product (r). The results revealed that an excellent separation of the components of interest could be achieved easily using simple nonforced and isocratic TLC. Such an interesting property of planar chromatography is mainly driven by the nonlinear relationship between k and Rf retention factors. This article also reports the practical advantages of TLC for the separation of estrogenic steroid mixtures at different temperatures.
Analysis of Combinatorial Natural Products by HPLC and CE
February 1st 2004In this article the authors report on a combinatorial natural product discovery methodology that uses a viral vector system to transfer secondary metabolite-related enzymes from C. roseus to tobacco cell cultures. Using high-resolution separation techniques, including HPLC, CE and MS, they describe the analysis of secondary metabolite patterns.
Detecting Mushroom Peptide Toxins in Body Fluids by Capillary Electrophoresis
September 1st 2001The Death Cap mushroom is the cause of most mushroom-related poisonings in the world. The author has developed a highly efficient, sensitive CE technique that toxicologists and forensic analysts can use to determine the poisonous peptides in body fluids of affected patients.
Whole-Column-Imaging Detection for Capillary Isoelectric Focusing and Capillary Electrophoresis
May 1st 2001In this article, the authors review recent developments in the research of whole-column-imaging detection for capillary electrophoresis (CE). Whole-column-imaging detection was developed for capillary isoelectric focusing, for which it proved to be an ideal detector. Several whole-column-imaging detectors -- including refractive index gradient imaging, UV-absorption imaging, and fluorescence imaging detectors -- have been studied. The capillary isoelectric focusing UV-absorption imaging technique even has been commercialized. The development of whole-column-imaging detection itself facilitates CE studies in many directions such as in electrophoretic dynamics within narrow channels, new separation modes, and two-dimensional separations. Whole-column-imaging detection also finds application in capillary zone electrophoresis.
The Analysis of Low Molecular Weight Carboxylic Acids by CE with Indirect UV Detection
September 1st 2000Capillary electrophoresis (CE) is a useful and versatile technique for a large number of applications. Devoting some discussion to the development of these reported methods to illustrate the separation approaches and strategies to obtain reproducible results, they also compare CE's advantages and disadvantages with those of the more typical method for each type of analysis.
Long-Term Analyses with Capillary Electrophoresis
July 1st 2000This month's installment of "CE Currents" deals with problems that may arise when using capillary electrophoresis for unattended, long-term operation, such as sample carryover, evaporation effects, capillary conditioning, capillary surface changes, buffer handling, capillary breakage, and detector lamp deterioration.