Selective on site separation and detection of molecules in diluted solutions with super-hydrophobic clusters of plasmonic nanoparticles

Nanoscale. 2014 Jul 21;6(14):8208-25. doi: 10.1039/c4nr00796d.

Abstract

Super-hydrophobic surfaces are bio-inspired interfaces with a superficial texture that, in its most common evolution, is formed by a periodic lattice of silicon micro-pillars. Similar surfaces reveal superior properties compared to conventional flat surfaces, including very low friction coefficients. In this work, we modified meso-porous silicon micro-pillars to incorporate networks of metal nano-particles into the porous matrix. In doing so, we obtained a multifunctional-hierarchical system in which (i) at a larger micrometric scale, the super-hydrophobic pillars bring the molecules dissolved in an ultralow-concentration droplet to the active sites of the device, (ii) at an intermediate meso-scale, the meso-porous silicon film adsorbs the low molecular weight content of the solution and, (iii) at a smaller nanometric scale, the aggregates of silver nano-particles would measure the target molecules with unprecedented sensitivity. In the results, we demonstrated how this scheme can be utilized to isolate and detect small molecules in a diluted solution in very low abundance ranges. The presented platform, coupled to Raman or other spectroscopy techniques, is a realistic candidate for the protein expression profiling of biological fluids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Hydrophobic and Hydrophilic Interactions
  • Metal Nanoparticles / chemistry*
  • Porosity
  • Rhodamines / chemistry
  • Serum Albumin, Bovine / analysis
  • Serum Albumin, Bovine / chemistry
  • Silicon / chemistry
  • Silver / chemistry
  • Solutions / chemistry
  • Spectrum Analysis, Raman
  • Surface Properties

Substances

  • Rhodamines
  • Solutions
  • Serum Albumin, Bovine
  • Silver
  • Silicon