FLUORESCENCE RESONANCE ENERGY-TRANSFER VISUALIZATION OF DNA AGGREGATES FORMED DURING ELECTROPHORETIC SEPARATIONS IN ULTRADILUTE HYDROXYETHYLCELLULOSE

Fluorescence resonance energy transfer (FRET) microscopy is used to ob serve structures of DNA aggregates formed during electrophoresis in ul tradilute hydroxyethylcellulose (HEC). FRET gives evidence of aggregat es with a tightly packed core and random entanglement of DNA in the ou ter portions. HEC concentrations also appear to play a role in aggrega te formation. DNA aggregates take longer to assemble in higher HEC con centration solutions and assume a less compact form than those formed at lower HEC concentrations.