COLLECTIVE RESONANCES IN TWO-DIMENSIONAL ARRAYS FOR COLLOIDAL METAL FILMS

摘要

The present invention provides strong nonradiative coupling of plasmon resonances of closely spaced, metal particles arranged in semi-regular, two-dimensional arrays disposed in a colloidal metal film. The colloidal films are formed on a substrate having functional groups with high affinity to an appropriate metal, such as silver. The substrates are exposed to a colloidal suspension of metal particles having average diameters in the range of 200-1000 Ångstroms for a desired time period, resulting in the adsorption of the metal to the substrate. The electrostatic interaction between individual particles causes a semi-regular two-dimensional array to be produced. Preferably, the means distance between particles is approximately equal to, or less than, their average diameter. The present invention may be utilized as an artificial antenna, for various different types of devices utilizing the energy of light. The present invention may also be used to perform surface-enhanced spectroscopies. The present invention may further be used in biomedical applications, such as homogenous immunoassays, analysis of whole blood, and DNA probes. The present invention has enabled work on combining of polymerase chain reaction (PCR), with detection of a DNA fragment of interest (DNA probe). The PCR and DNA probe are combined in a vial, with the present invention obviating the need for any intermediate steps, to greatly facilitate DNA probe techniques.