We investigated the performance of several commonly used fluorescent dyes after exposure to a simulated Europa mission total ionizing radiation dose of 300 krad (3 kGy) applied using a 60Co source. Dyes irradiated in aqueous solution or as lyophilized powders were evaluated for absorbance and emission spectra, quantum yield, and where appropriate, ability to label cells or nucleic acids. Although some dyes showed significant increase or decrease in quantum yield with the dose, their spectra and cell-labeling properties remained essentially unchanged after irradiation in powder form. Irradiation in aqueous solution led to significantly greater changes, including a large blue shift in the DNA intercalator propidium iodide. These results suggest that many fluorescent probes are appropriate for use in astrobiological missions to Europa, but that SYTO9 and propidium iodide should be used with caution or not mixed with each other, as is commonly done in “Live/Dead” labeling applications.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 190 • No. 6