Microalgae—abundant, single-cell organisms that thrive in lakes, ponds, rivers and oceans—could one day become a solar energy-powered green factory that can replace our fossil fuel-based industry – if the algae can be genetically engineered to improve their biosynthetic capabilities.

   That’s a big if, because so far the cell wall that surrounds the individual algae has proven to be a formidable barrier to gene delivery.

   Judging from the results of a recent Gordon Research Conference (GRC), Asst. Prof. Hitomi Mukaibo and her lab are demonstrating encouraging progress in overcoming that barrier.

   Their experiment, “Impaling Microalgae Cells using Protruding Needle Arrays,” was one of four projects to receive RSC (Royal Society of Chemistry) Analyst Poster prizes at the GRC on Bioanalytical Sensors: Twenty-first Century Technologies for Probing Biological Systems, held at Salve Regina University in Newport, R.I. More than 120 posters were shown.

    Mukaibo was invited to give a five-minute pitch talk at the conference, and was delighted by how many people came up to her who were “interested in our work, the structure we’re making, and also in collaborating with us. It was a great honor to be invited to talk, and be greeted with so much enthusiasm,” Mukaibo said.

   Mukaibo’s project uses arrays of microneedles with nanometer-sized tips, which can impale the algae without killing them. Mukaibo’s experiment has demonstrated that the metallic needles not only can successfully introduce genetic material into microalgae, but also can act as electrodes to detect photosynthetic biocurrent from the algal cells.

    “I’m very excited about this work,” said Mukaibo.  “Interfacing living cells with synthetic microstructures is an emerging field that sparks our imagination, and I think that’s what appealed to the people at the conference.”

    Her lab, which this past academic year included two Ph.D. candidates, three master’s students and four undergraduates, is also working on improved designs of anodes for lithium-ion batteries with longer life and higher energy density.