Abstract
Modification of rectified Nomarski differential interference contrast optics (Nikon) and the epi-illumination system (Nikon IGS-cube) improved the detection of colloidal gold particles with analog video enhanced microscopy. Immuno-gold labelled microtubules of Haemanthus endosperm are visualized at a level of detection unmatched in conventional light micro-scopy. Single gold, or gold silver enhanced particles in suspension viewed with the modified epi-illumination after pressure injection into cells, are well distinguished from other granular cell components. Immuno-gold has also been detected on the surface of chromosomes and the nuclear envelopes in cells during the rapid experimental disassembly of microtubules. Thus, under certain conditions tubulin in a form other than microtubules may be detected. Practical applications of this "optical stain" for non fading immuno-gold 5-40 nm markers are discussed.
