Abstract: A method of detecting melamine which includes providing a quantity of SERS-active particles and mixing the SERS-active particles with a solution containing melamine. The method further includes detecting a surface enhanced Raman spectrum of the melamine. The foregoing method may optionally include aggregating the SERS-active particles. Aggregation may occur before or after the SERS-active particles are mixed with a solution containing melamine. The method of detecting melamine may optionally include concentration of the SERS-active particles. The method may further include mixing a chaotropic agent having a higher affinity for a selected binding site than melamine into the solution containing melamine. The method may further include mixing a quantity of a SERS-active standard having a known SERS spectrum with the solution containing melamine and SERS-active particles. Assay apparatus and systems are also disclosed.

Abstract: A method of detecting melamine which includes providing a quantity of SERS-active particles and mixing the SERS-active particles with a solution containing melamine. The method further includes detecting a surface enhanced Raman spectrum of the melamine. The foregoing method may optionally include aggregating the SERS-active particles. Aggregation may occur before or after the SERS-active particles are mixed with a solution containing melamine. The method of detecting melamine may optionally include concentration of the SERS-active particles. The method may further include mixing a chaotropic agent having a higher affinity for a selected binding site than melamine into the solution containing melamine. The method may further include mixing a quantity of a SERS-active standard having a known SERS spectrum with the solution containing melamine and SERS-active particles. Assay apparatus and systems are also disclosed.

Abstract: Methods and systems for the use of surface-enhanced Raman scattering nanotags (SERS nanotags) in various assay platforms which feature accelerated reaction kinetics. One embodiment includes a method detecting a substance of interest by associating a SERS nanotag with the substance of interest while accelerating the reaction kinetics of the association steps. This method also includes detecting a Raman spectrum of a reporter molecule associated with the SERS nanotag. The reaction kinetics of the assay may be accelerated by applying microwave radiation to the sample, heating the sample, agitating the sample, mixing the sample, vibrating the sample or other methods.

Abstract: Methods and compositions of matter are disclosed for creating tags such as SERS nanotags which are dispersible in an organic solvent. The tags are inherently hydrophilic and may be made dispersible in an organic solvent by associating the tag with an amphiphilic polymer. Alternatively, a tag may be associated with a surfactant. In another embodiment a tag having an encapsulant of a silicon containing material may be made dispersible in an organic solvent by modifying the encapsulant surface with a hydrophobic silane. In addition, a tag having an encapsulant of a silicon containing material may be modified by the esterification of the encapsulant with an alcohol.