Resolving the Complexity of Biomacromolecules Using Multiple Modes of Chromatography
October 1st 2017To resolve and quantitate monoclonal antibodies and antibody–drug conjugates, analytical scientists need various chromatographic modes, such as sizeexclusion, ion-exchange, hydrophobic interaction, and hydrophilic interaction chromatography. Here, we provide advice for making the most of each mode.
Resolving the Complexity of Biomacromolecules Using Multiple Modes of Chromatography
October 1st 2017Separating proteins and antibodies is a unique analytical challenge because of the complexity of the analytes. Both sample heterogeneity, because of a number of chemical modifications to the analyte, and nonspecific binding to the silica surface often result in chromatographic peak broadening and tailing. This instalment of “Column Watch” focuses on several different chromatographic strategies that analytical scientists can use to resolve and quantitate various biomacromolecules, including monoclobal antibodies (mAbs) and antibody–drug conjugates (ADCs). Selected aspects of size-exclusion, hydrophobic interaction, ion-exchange, hydrophilic interaction, and reversed-phase chromatography are discussed.
Chinese American Chromatography Association Invites Awards Nominations
September 27th 2017The Chinese American Chromatography Association (CACA) invites nominations for three awards: the 2018 CACA Young Investigator Award; the 2018 CACA Student Excellence Award; and the HPLC 2018 Student Travel Award.
Investigating the Effectiveness of Caviar in Cosmetic Skin Creams
September 12th 2017Researchers from the University of Torino have developed a novel HPLC–HRMS application for evaluating cosmetic ingredient composition. The application was used to analyze and compare sturgeon eggs, commonly known as caviar, and brill eggs, and their use in beauty creams as lipid sources.
Recent Developments in Microchip Electrophoresis
September 12th 2017Capillary electrophoresis (CE) is routinely used for chemical and biochemical analysis methods, and recently the technique has been implemented on microchips. R. Scott Martin, a professor and chair of chemistry at Saint Louis University, St. Louis, Missouri, USA, has been investigating ways to improve these techniques for years. He recently spoke to us about his research coupling microchip electrophoresis with electrochemical detection, coupling continuous flow with microchip electrophoresis with valving, coupling microchip CE with microdialysis sampling and electrochemistry, and more.
The LCGC Blog: Automated Method Development in Liquid Chromatography
September 12th 2017The ability to rapidly screen stationary phases through column-switching capabilities provides significantly greater efficiency in method development than was previously possible. The approach does require some additional hardware and software. And, while such capabilities may limit the ability to expand one’s literary knowledge during excessive months in the laboratory developing separation methods, real progress to key decision points for method optimization can be realized instead.
Effects of External Influences on GC Results
September 1st 2017Small differences in process gas chromatography (GC) results from the same sample stream over time can indicate corresponding changes in target analyte concentrations, or the fluctuations might be due to external influences on the instrument. This instalment of ”GC Connections” explores ways to examine such results and better understand their significance.
LC–MS Characterization of Mesquite Flour Constituents
September 1st 2017Using a liquid chromatography–mass spectrometry (LC–MS) method in conjunction with two complementary types of chromatographic retention modes-reversed phase and aqueous normal phase-various compounds present in mesquite flour extracts were identified. Because of the diverse types of chemical constituents found in such natural product extracts, a single chromatographic mode may not be sufficient for a comprehensive characterization. However, the combination of reversed-phase and aqueous normal phase LC can encompass a wide range of analyte polarity. This characterization of the composition of mesquite flour could be used in future studies to elucidate the beneficial health effects of its consumption.
Results Correlation with External Influences
September 1st 2017In the previous instalment, we presented a case of periodically fluctuating data that did not lend itself well to trend analysis with conventional statistical methods. The data did appear to have a strong regular fluctuation, but its relationship to other observations was not clear. This instalment addresses methods for teasing out external influences on trending data.
Highlights from HPLC 2017 Symposium
September 1st 2017The 45th International Symposium on High Perfomance Liquid Phase Separations and Related Techniques (HPLC 2017), cochaired by Michal Holc€apek and František Foret, was held 18–22 June in Prague, Czech Republic. This instalment covers some of the highlights observed at the symposium, including advances in large-molecule separations, multidimensional chromatography, and areas of growing application of high performance liquid chromatography (HPLC). In addition, trends and perspectives on future developments in HPLC noted from the conference are presented.