Nanoparticle based biological assays

Abstract

An introduction to the utilization of plasmon resonant particles as optical labels for diverse biological applications is presented. Plasmon resonant particles (PRP(TM)) (Seashell Technology LLC, La Jolla, CA) are sub- micron (40-100 nanometer), ultra-bright, nonbleaching, multicolor, light scattering objects that can be attached to standard biomolecules. The basic concepts and use of PRP in various biological applications such as immunoassays and histology, including in-situ hybridization, and tissue labeling are discussed. We suggest that this new label will replace and/or complement the traditional labels presently used that are based on radioactivity, fluorescence, or chemiluminescence. Since the detection of each individual label is readily performed, the measured signal is a simple count of all of the detected labels. Thus, the ultimate sensitivity of the assay is set by both the degree of label binding to the individual 'target' molecular entity, and the corresponding number of labels that bind nondiscriminately.