Harvard silicon chip synthesizes 64 DNA strands enzymatically in parallel via localized pH control

The device repurposes neuron-recording electrode arrays into concentric ring pairs that confine acidic microenvironments for deprotection steps while maintaining bulk neutral pH. Each cycle adds one base only at electrically addressed sites, achieving 64 unique sequences without organic solvents. This marks a fourfold increase over prior enzymatic demonstrations and directly links CMOS precision current control to nucleotide assembly chemistry.

Enzymatic synthesis on silicon opens routes to distributed DNA manufacturing for data storage, where 39-mer oligos serve as addressable blocks in archival systems already prototyped by Microsoft and Catalog. It also supports on-demand CRISPR guide libraries or diagnostic probes without centralized phosphoramidite facilities. The approach sidesteps solvent toxicity and facility scale, aligning with emerging decentralized biofoundry models that reduce logistics bottlenecks in synthetic biology supply chains.

Key limitation remains short strand length and unquantified error rates at scale; full sequencing verification of all 64 products is needed. Strengthening evidence requires a follow-on study demonstrating 200+ nt synthesis with NGS-confirmed fidelity above 99 percent across >256 sites within two years.