Abstract: A novel hybridization diagnostic technique is involved employing micromanipulation of cells for detection of DNA or RNA in the cells. Cellular suspensions are employed, the DNA or RNA purified by microextraction using liquid media having differential solubilization properties, whereby the nucleic acid is retained in an aqueous microdrop. The nucleic acid in the microdrop may then be assayed with a nucleic acid probe in accordance with conventional ways.

Abstract: Microinjection techniques for plant protoplasts utilize a holding pipette for immobilizing the protoplast while an injection pipette is utilized to inject the macromolecule. In order to manipulate the protoplasts without damage, the protoplasts are cultured for from about 1 to 5 days before the injection is performed to allow for partial regeneration of the cell wall. It was found that injection through the partially regenerated cell wall could still be accomplished and particular compartments of the cell could be targeted. The methods are particularly useful for transformation of plant protoplasts with exogenous genes.