{
  "abstract": "Polymers used as substrate and encapsulation for implantable devices are typically deposited layer-by-layer, leaving polymer-polymer interfaces that adhere poorly and become a critical failure point. Thermoplastic polyurethane (TPU) elastomers combine four properties not found together in any other candidate: decades of clinical use in long-term implants and availability in medical grade, a stiffness well below that of polyimide and parylene C, compatibility with microfabrication, and thermoplastic self-fusion, which removes the polymer-polymer interface entirely. This work introduces TPU as a base material for soft, high-density neural interfaces and demonstrates one route to realizing them. Gold is patterned on a sacrificial copper sheet by maskless lithography and transferred into TPU by vacuum lamination, giving conformally coated tracks down to 15 um at 30 um pitch within a single, merged polymer body. An additional electroplating step produces a nanostructured pinecone gold surface that increases the electrochemically active area of the electrodes, approximately doubling the charge injection capacity. Daisy-chain silicon chips were also embedded within the soft polymer body. The films transmit up to 88% at 470 nm, a wavelength commonly used for optogenetics. TPU showed no cytotoxicity towards differentiated SH-SY5Y cells and only a mild tissue response after 9.5 months of subcutaneous implantation in rats.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Microelectronics, Delft University of Technology, Delft, The Netherlands"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 22,
  "authors": [
    {
      "name": "A. Pak"
    },
    {
      "name": "A. I. Velea"
    },
    {
      "name": "T. Hosman"
    },
    {
      "name": "J. Wilson"
    },
    {
      "name": "R. Panskus"
    },
    {
      "name": "M. Seckel"
    },
    {
      "name": "P. de Anta Dardagan"
    },
    {
      "name": "R. Schmidt"
    },
    {
      "name": "D. Horvath"
    },
    {
      "name": "K. Toth"
    },
    {
      "name": "D. Meszena"
    },
    {
      "name": "A. Gollhardt"
    },
    {
      "name": "N. Bakhshaee Babaroud"
    },
    {
      "name": "B. Pahl"
    },
    {
      "name": "E. Zingkou"
    },
    {
      "name": "A. Kolianou"
    },
    {
      "name": "G. Sotiropoulou"
    },
    {
      "name": "S. Negi"
    },
    {
      "name": "F. Solzbacher"
    },
    {
      "name": "C. Kallmayer"
    },
    {
      "name": "I. Ulbert"
    },
    {
      "affs": [
        0
      ],
      "name": "V. Giagka"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/aghnswxk5t7bq.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.04.755411",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.755411v1.full",
  "id": "aghnswxk5t7bq",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.755411v1",
  "language": null,
  "licence": "CC-BY-NC",
  "licence_label": "CC BY-NC",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "bioengineering"
    ],
    [
      "openalex",
      "2804|Neuroscience and Neural Engineering"
    ]
  ],
  "openalex": "W7221702368",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.755411v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-04",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/aghnswxk5t7bq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:33Z",
      "native_id": "10.64898/2026.10.04.755411",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.10.04.755411v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:bioengineering",
      "subfield": "systems-synthetic"
    }
  ],
  "title": "Thermoplastic polyurethane as a base material for soft, high-density neural interfaces",
  "title_text": "Thermoplastic polyurethane as a base material for soft, high-density neural interfaces",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:33Z",
  "url": "https://research.draconitic.com/paper/aghnswxk5t7bq",
  "venue": "bioRxiv",
  "versions": []
}