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bioRxiv · 10.1101/2023.05.28.542285

Toward single cell tattoos: Biotransfer printing of lithographic gold nanopatterns on live cells

Kwok, K. S.·Zuo, Y.·Choi, S. J.·Pahapale, G. J.·Gu, L.·Gracias, D. H.
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Abstract

Lithographic nanopatterning techniques like photolithography, electron-beam lithography, and nanoimprint lithography (NIL) have revolutionized modern-day electronics and optics. Yet, their application for creating nano-bio interfaces is limited by the cytotoxic and two-dimensional nature of conventional fabrication methods. Here, we present a biocompatible and cost-effective transfer process that leverages (a) NIL to define sub-300 nm gold (Au) nanopattern arrays, (b) amine functionalization of Au to transfer the NIL-arrays from a rigid substrate to a soft transfer layer, (c) alginate hydrogel as a flexible, degradable transfer layer, and (d) gelatin conjugation of the Au NIL-arrays to achieve conformal contact with live cells. We demonstrate biotransfer printing of the Au NIL-arrays on rat brains and live cells with high pattern fidelity and cell viability and observed differences in cell migration on the Au NIL-dot and NIL-wire printed hydrogels. We anticipate that this nanolithography-compatible biotransfer printing method could advance bionics, biosensing, and biohybrid tissue interfaces. TOC Figure O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=97 SRC="FIGDIR/small/542285v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@16f6e1corg.highwire.dtl.DTLVardef@a60bacorg.highwire.dtl.DTLVardef@1485d06org.highwire.dtl.DTLVardef@1d365c9_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Kwok, K. S., Zuo, Y., Choi, S. J., Pahapale, G. J., Gu, L., Gracias, D. H.. 2023-05-28. Toward single cell tattoos: Biotransfer printing of lithographic gold nanopatterns on live cells. https://doi.org/10.1101/2023.05.28.542285

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