Water-Transfer Electronics

Hydroprinted liquid-metal circuits transferred onto skin via PVA carrier

My role

I led this project end to end, from the ink through the transfer process to the on-skin demonstrator.

Concept

A PVA-carrier water-transfer process that hydroprints PDA-LM circuits onto arbitrary surfaces — including human skin — in seconds, without sintering and without primer. The carrier dissolves on contact with water, leaving a conformal LM trace that is immediately conductive.

Why it matters

Existing tattoo electronics typically require either (i) skin-side adhesion layers, (ii) post-transfer thermal/mechanical activation, or (iii) organic solvents that limit on-skin deposition. The PDA-LM ink solves all three because its catechol chemistry already provides both adhesion and percolation.

Phase 1 demonstration

A 4-LED circuit water-transferred onto the back of the hand, driven by an external coin-cell, validates the conductivity-after-transfer claim on a real biological substrate.

Roadmap

  • Phase 2: integrate AD5941 EC front-end + BLE for self-contained skin-mounted biosensing
  • Phase 3: miniaturize to a 3×3 cm tattoo sticker with on-board NFC harvesting