A galinstan expansion femtosyringe for microinjection of eukaryotic organelles and prokaryotes

A galinstan expansion femtosyringe enables femtoliter to attoliter samples to be introduced into prokaryotes and subcellular compartments of eukaryotes. The method uses heat-induced expansion of galinstan (a liquid metal alloy of gallium, indium, and tin) within a glass syringe to expel samples through a tip diameter of about 0.1 mu m. The narrow tip inflicts less damage than conventional capillaries, and the heat-induced expansion of the galinstan allows fine control over the rate of injection. We demonstrate injection of Lucifer Yellow and Lucifer Yellow-dextran conjugates into cyanobacteria, and into nuclei and chloroplasts of higher organisms. Injection of a plasmid containing the bla gene into the cyanobacterium Phormidium laminosum resulted in transformed ampiciltin-resistant cultures. Green fluorescent protein was expressed in attached leaves of tobacco and Vicia faba following injection of DNA cantaining its gene into individual chloroplasts.