Devices

Sub-micrometre-thick, centimetre-scale mesh electronics that unfold after injection through a needle as small as 100 µm. Harvard, 2015, in mouse brain.

Device — Intracortical

Syringe-injectable mesh electronics

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mesh electronics · injectable · flexible · Lieber · Harvard · chronic · academic · preclinical

Syringe-injectable mesh electronics

One-line verdict: A mesh so thin and open that it can be pushed through a needle and then unfolds inside tissue, trading the stiffness of conventional probes for delivery that only a syringe can do.

Quick tags: Recording · Intracortical · Species: Mouse · Published: 2015

Overview

What it is: A macroporous electronic mesh, sub-micrometre thick and centimetre scale, loaded into a syringe and injected through needles as small as 100 µm in diameter. After injection it unfolds in the cavity or tissue.

Why it matters: Most implants fight the brain’s mechanics. This one tries to disappear into it: the authors report tight integration and low chronic immunoreactivity in several brain regions, and multiplexed neural recording in vivo.

Status: Academic demonstration in mice and in man-made structures, with greater than 90% device yield reported for injection into cavities, dense gels and tissue.

Spec Card Grid

Identity

  • Authors: Jia Liu, Tian-Ming Fu, Zengguang Cheng and co-authors; senior authors Ying Fang and Charles M. Lieber
  • Org: Harvard University, with the National Center for Nanoscience and Technology, Beijing
  • Published: Nature Nanotechnology, 10(7):629-636, June 2015
  • Species: mouse

Geometry & Architecture

  • Form factor: macroporous mesh, centimetre scale in plane
  • Thickness: sub-micrometre
  • Delivery: syringe injection through needles down to 100 µm diameter, then unfolding
  • Demonstrated applications: strain monitoring in polymer cavities, brain integration, in vivo multiplexed neural recording

Evidence and limits

  • Injection yield: greater than 90% into cavities, gels and tissue
  • Tissue response: low chronic immunoreactivity reported in several brain regions
  • Not covered by this paper: long-term human use. Channel counts and recording duration are in the paper and are not reproduced here.

Engineering Verdict

Strengths: minimally invasive delivery, mechanical match to tissue, large coverage volume.

Limitations: the connection from a free-floating mesh to external electronics is the hard engineering problem; delivery by injection gives limited control over final position.

References