Gold Nanoparticle Technology


Nanoparticles

Nanoparticles, as used in Nanosphere’s Verigene®
System and tests, are typically 13-20 nanometers (nm)
in diameter. One nanometer is approximately one
ten-thousandth (1/10,000) of the width of a human hair.

Depending upon the application, each nanoparticle is functionalized with either a defined number of oligonucleotides (i.e., short pieces of DNA or RNA with sequences complementary to target sequences of clinical interest) or a defined number of antibodies that are specific to a particular protein of interest (e.g., prostate-specific antigen [PSA], cardiac troponin I [cTnI]).
 

Gold Nanoparticle Technology

Gold nanoparticle probes possess several properties that make them ideal for diagnostic applications:

  1. Allows increased sensitivity by several orders of magnitude; light scattered from one nanoparticle is equivalent to the light emitted from 5x105 (500,000) fluorophores.  Tests that employ gold nanoparticles functionalized with antibodies, for example, are 2-3 orders of magnitude more sensitive than ELISA-based methods.
  2. Enables high-specificity for both nucleic acid and protein detection.  For nucleic acid detection, single-base pair specificity is achieved due to assay reaction kinetics where gold nanoparticle probes, comprised of target-specific oligonucleotides, permit hybridization to target DNA over a very narrow temperature range.
  3. Reduces background noise (i.e. signal-to-signal) due to minimal non-specific binding of the gold nanoparticle probes, which in turn, create an enhanced assay signal.
  4. Requires little or no inventory control.  The nanoparticle probes are extremely stable, have a long shelf-life, and are non-toxic.