A comparison of TO-PRO-1 iodide and 5-CFDA-AM staining methods for assessing viability of planktonic algae with epifluorescence microscopy

J Microbiol Methods. 2012 Jun;89(3):216-21. doi: 10.1016/j.mimet.2012.03.005. Epub 2012 Mar 14.

Abstract

Two fluorescent dyes, TO-PRO-1 iodide and 5-CFDA-AM, were evaluated for LIVE/DEAD assessment of unicellular marine algae Brachiomonas submarina and Tetraselmis suecica. Epifluorescence microscopy was used to estimate cell viability in predetermined mixtures of viable and non-viable algal cells and validated using microplate growth assay as reference measurements. On average, 5-CFDA-AM underestimated live cell abundance by ~25% compared with viability estimated by the growth assay, whereas TO-PRO-1 iodide provided accurate viability estimates. Furthermore, viability estimates based on staining with TO-PRO-1 iodide were not affected by a storage period of up to one month in -80°C, making the assay a good candidate for routine assessment of phytoplankton populations in field and laboratory studies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Cell Survival
  • Chlorophyta / physiology*
  • Fluoresceins / metabolism*
  • Fluorescent Dyes / metabolism*
  • Microscopy, Fluorescence / methods*
  • Organic Chemicals / metabolism
  • Staining and Labeling / methods*

Substances

  • 5-carboxyfluorescein diacetate acetoxymethyl ester
  • Fluoresceins
  • Fluorescent Dyes
  • Organic Chemicals
  • TO-PRO-1