Aluminum acid alizarin violet: a general purpose nuclear fluorochrome

Acid alizarin violet N in an acidified aluminum potassium sulfate solution (AAV) is presented as a nuclear fluorochrome. We demonstrate using 1 N HCl, deoxyribonuclease, and ribonuclease digestion methods that this stain has specificity for nucleic acids similar to other aluminum mordant stains in 95% ethanol-fixed material. The method presented gives stable preparations and is resistant to fading for at least two years. Strong fluorescence of AAV stained material is detected under conventional mercury vapor lamp and argon ion laser illumination. AAV stained confocal scanning laser microscope (CSLM) images are collected in the red channel of the microscope (detecting lambda > 600 nm), there being no AAV emission in the green channel (detecting lambda 527-565 nm). The xanthene dyes eosin Y and dichlorofluorescein are used as counterstains and can be imaged in both channels. We present a method for use with the CSLM, utilizing double imaging techniques.