System and method for Raman spectroscopy assay using paramagnetic particles

摘要

A Raman spectroscopy technique allows an analyte, a paramagnetic particle, and a spectral enhancement particle to combine in solution and for the combination product to be localized by a magnetic field for analysis. The spectral enhancement particle may be comprised of an active SERS metal particle with or without a material coating. The spectral enhancement particle may function as a reporter for the presence of the analyte or merely increase the magnitude of the Raman spectrum of the analyte. The technique is applicable to both immunoassays and chemical assays. Multiple spectral enhancement particle reporters may be measured in a single assay that can detect multiple analytes using the SERS effect.

主权项

1. A method for performing an assay to determine the presence of at least one analyte, comprising:
binding in solution within a sample chamber at least one of a plurality of spectral enhancement particles, at least one of a plurality of paramagnetic particles including a coating, and at least one analyte to form a combination product, wherein the spectral enhancement particles bind with the at least one analyte or the paramagnetic particles and the paramagnetic particles bind with the at least one analyte or the spectral enhancement particles, should the at least one analyte be present in the solution; applying a magnetic field to the solution from a magnet positioned adjacent the sample chamber; concentrating at least a portion of any combination product and at least a portion of the plurality of paramagnetic particles not part of the combination product in the solution into a condensation at a discrete location within the sample chamber using the influence of the magnetic field; interrogating the discrete location within the sample chamber with a laser beam to obtain spectral information, wherein the interrogation laser beam is passed through the sample chamber to the discrete location within the sample chamber and a Raman scattered light signal including the spectral information is passed back through the sample chamber; receiving the Raman scattered light signal including the spectral information from the sample chamber; and using the spectral information to detect the presence of, quantify the amount of, or both detect the presence of and quantify the amount of, said at least one analyte in the solution, wherein the spectral information comprises spectral information derived from the coatings of the plurality of concentrated paramagnetic particles and the spectral information derived from the coatings of the paramagnetic particles is used as an internal standard in the detection operation.