Selective functionalization and loading of biomolecules in crystalline silicon nanotube field-effect-transistors

Nanoscale. 2014 Jul 21;6(14):7847-52. doi: 10.1039/c4nr01508h.

Abstract

Crystalline silicon nanotubes (Si NTs) provide distinctive advantages as electrical and biochemical analysis scaffolds through their unique morphology and electrical tunability compared to solid nanowires or amorphous/non-conductive nanotubes. Such potential is investigated in this report. Gate-dependent four-probe current-voltage analysis reveals electrical properties such as resistivity to differ by nearly 3 orders of magnitude between crystalline and amorphous Si NTs. Analysis of transistor transfer characteristics yields a field effect mobility of 40.0 cm(2) V(-1) s(-1) in crystalline Si NTs. The hollow morphology also allows selective inner/outer surface functionalization and loading capability either as a carrier for molecular targets or as a nanofluidic channel for biomolecular assays. We present for the first time a demonstration of internalization of fluorescent dyes (rhodamine) and biomolecules (BSA) in Si NTs as long as 22 μm in length.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cattle
  • Crystallization
  • Fluorescent Dyes / chemistry*
  • Nanotubes / chemistry*
  • Nanowires / chemistry
  • Rhodamines / chemistry
  • Serum Albumin, Bovine / chemistry*
  • Serum Albumin, Bovine / metabolism
  • Silicon / chemistry*
  • Transistors, Electronic*

Substances

  • Fluorescent Dyes
  • Rhodamines
  • Serum Albumin, Bovine
  • Silicon