Harvard engineers have turned an ordinary silicon chip into a miniature DNA factory. Writing in Nature Electronics, the team led by Donhee Ham describes a device that synthesises 64 different strands of DNA at once, using only electric currents and water-based enzymes. Tiny ring-shaped electrodes fire protons at precise spots on the chip, nudging each strand to grow letter by letter — a far cleaner method than the solvent-heavy chemistry that dominates DNA manufacturing today.
The promise is tantalising: portable machines that print bespoke genetic material for medicine or vaccines, and perhaps one day vast archives of data stored in DNA itself. Yet caution is warranted. The process still struggles to scale, hampered by stray molecules that blur the chemistry, and writing genetic code cheaply raises thorny questions about biosecurity. Building the very alphabet of life, it turns out, is becoming an engineering problem.