Virus Particle Characterization
The Application Notebook
Viruses are packets of infectious nucleic acid (either DNA or RNA) surrounded by a protective coat consisting of a large number of protein subunits. Because viruses can cause various diseases - some life-threatening - characterizing virus particles thoroughly in terms of their size distribution, aggregation and absolute counts-per-unit volume is of extreme importance.
Wyatt Technology Corporation, Santa Barbara, California, USA.
Viruses are packets of infectious nucleic acid (either DNA or RNA) surrounded by a protective coat consisting of a large number of protein subunits. Because viruses can cause various diseases — some life-threatening — characterizing virus particles thoroughly in terms of their size distribution, aggregation and absolute counts-per-unit volume is of extreme importance.
Though size exclusion chromatography (SEC) has been the primary tool for separating aggregates of molecules, it is generally not appropriate for fractionating viruses because viruses and their aggregates are subject to shearing degradation by the stationary phase. Moreover, they can also be caught by the columns because of their large sizes.
The Eclipse, a particle separation system based upon field flow fractionation (FFF), effectively replaces SEC as a perfect alternative for virus characterization. Because it is analogous to an HPLC separation, the Eclipse — combined with MALS — makes a physical separation of the particles and then sizes them directly as they elute.
This application note reports the results obtained from a set of virus particles fractionated by Eclipse and sized by the 18-angle DAWN EOS on-line multi-angle light scattering instrument.
Figure 1 shows the radius measured by the DAWN EOS detector (from initial slope of angular dependence) versus elution time for two different virus strains. The plots show clearly that aggregates were found in both viruses and much more in Virus 2. Results from duplicate injections of Virus 1 show the excellent reproducibility of the Eclipse-MALS system.
Figure 1
The results are also shown by the cumulative number distribution plots in Figure 2. The cumulative number distribution yields quantitative information on the percentage of aggregates present in each virus strain: 5% for Virus 1 and 95% for Virus 2.
Figure 2
The success of the virus characterization demonstrated above confirms that the Eclipse-MALS approach is an indispensable tool for charactering virus particles — and other colloidal particles — in solution. This approach is especially important when the absolute particle distributions are vital.
Wyatt Technology Corporation
6300 Hollister Avenue, Santa Barbara, California 93117, USA
tel. +1 805 681 9009 fax +1 805 681 0123
Website: www.wyatt.com
2024 EAS Awardees Showcase Innovative Research in Analytical Science
November 20th 2024Scientists from the Massachusetts Institute of Technology, the University of Washington, and other leading institutions took the stage at the Eastern Analytical Symposium to accept awards and share insights into their research.
Inside the Laboratory: The Richardson Group at the University of South Carolina
November 20th 2024In this edition of “Inside the Laboratory,” Susan Richardson of the University of South Carolina discusses her laboratory’s work with using electron ionization and chemical ionization with gas chromatography–mass spectrometry (GC–MS) to detect DBPs in complex environmental matrices, and how her work advances environmental analysis.
AI and GenAI Applications to Help Optimize Purification and Yield of Antibodies From Plasma
October 31st 2024Deriving antibodies from plasma products involves several steps, typically starting from the collection of plasma and ending with the purification of the desired antibodies. These are: plasma collection; plasma pooling; fractionation; antibody purification; concentration and formulation; quality control; and packaging and storage. This process results in a purified antibody product that can be used for therapeutic purposes, diagnostic tests, or research. Each step is critical to ensure the safety, efficacy, and quality of the final product. Applications of AI/GenAI in many of these steps can significantly help in the optimization of purification and yield of the desired antibodies. Some specific use-cases are: selecting and optimizing plasma units for optimized plasma pooling; GenAI solution for enterprise search on internal knowledge portal; analysing and optimizing production batch profitability, inventory, yields; monitoring production batch key performance indicators for outlier identification; monitoring production equipment to predict maintenance events; and reducing quality control laboratory testing turnaround time.
Infographic: Be confidently audit ready, at any time and reduce failures in pharma QC testing
November 20th 2024Discover how you can simplify the audit preparation process with data integrity dashboards that provide transparency to key actions, and seamlessly track long-term trends and patterns, helping to prevent system suitability failures before they occur with waters_connect Data Intelligence software.
Critical Role of Oligonucleotides in Drug Development Highlighted at EAS Session
November 19th 2024A Monday session at the Eastern Analytical Symposium, sponsored by the Chinese American Chromatography Association, explored key challenges and solutions for achieving more sensitive oligonucleotide analysis.
