Open Menu REQUEST A QUOTE | LOGIN Home > Services > Toxicology > In vitro Comet Genotoxicity Service In vitro Comet assay Cyprotex have partnered with Gentronix, specialists in genotoxicity screening, to offer the in vitro Comet assay. The Comet assay, also called the single cell gel electrophoresis (SCGE) assay is a sensitive, rapid and relatively simple method for detecting DNA damage at the individual eukaryotic cell level1. Electrophoresis is performed on exposed cells that have been embedded in agarose microgels. Damage resulting in DNA fragmentation is detectable by migration away from the nucleus giving a comet-like appearance with the head consisting of intact DNA and the tail consisting of damaged DNA. The assay delivers rapid and sensitive DNA damage assessment with the benefit of low compound requirements. The Comet assay complements other genotoxicity assays to provide a mechanistic insight into genotoxicity. In addition to the capability of the Comet assay to identify DNA damage at the single cell level, other significant advantages include its sensitivity for detecting low levels of DNA damage, the requirement for only small numbers of cells per sample, its ease of application, and the short time needed to perform the assay. 2Liao W, McNutt MA and Zhu W-G (2009) Methods 48; 46-53 Protocol In vitro Comet genotoxicity protocol Test System Alkaline Comet (single cell gel electrophoresis) Cell Line TK6 cells Test Article Concentration 5 serial dilutions, typically 2-fold; e.g. 1000, 500, 250, 125, 62.5 µg/mL Incubation Time 3 hr exposure time Quality Controls 1% DMSO (negative control) Etoposide (positive genotoxic control) Cell Viability Assesment Propidium iodide exclusion using flow cytometry; 80% relative survival required for Comet processing Test Article Requirements 10 mg solid - Other compound preparations are acceptable Data Analysis 50 comets per compound dose acquired from two agarose gels (25 from each gel) Data Delivery Written report presenting overall results Excel worksheets with full graphical dose response data for genotoxicity including % tail intensity Data Data from the in vitro Comet genotoxicity assay The in vitro Comet assay from Gentronix has been validated against a number of different genotoxic and non-genotoxic compounds. Figure 1 Graphs illustrating mean tail intensity data from the Gentronix Comet assay for non-genotoxic (cycloheximide) and genotoxic (etoposide, hydrogen peroxide and 4-nitroquinoline-1-oxide) compounds (mean ± sd; n=3). References 1 Singh NP et al. (1988) Exp Cell Res 175; 184-191 2 Liao W et al. (2009) Methods 48; 46-53 Learn More Learn more about toxicology in our popular Mechanisms of Drug-Induced Toxicity guide ORDER YOUR COPY Our Services ADME PK Toxicology In Silico Physicochemical Profiling GET A QUOTE PRODUCT SHEET ADME GUIDE DDI GUIDE TOX GUIDE United Kingdom (HQ) No.24 Mereside, Alderley Park Nether Alderley Cheshire SK10 4TG United Kingdom Tel: +44 (0) 1625 505100 Fax: +44 (0) 1625 505199 enquiries@cyprotex.com United States 313 Pleasant St., Watertown, MA 02472 USA Tel: +1-888-297-7683 Fax: +1-617-812-0712 enquiries@cyprotex.com VIEW CONTACT DETAILS Legal Privacy Site map Careers This website is intended to assist industry participants, customers and employees to understand Cyprotex's global operations and ambitions. This website was last updated on 27th October 2021