Abstract: A particulate composition comprises a plurality of particles wherein at least one of the particles comprises at least two different crystalline and/or glass phases, each phase comprising a host lattice and a dopant sensitive to electromagnetic radiation. The different phases simultaneously produce different responses on exposure to photons of the same energy, whereby the output from the particulate composition when exposed to said photons is the sum of the responses from the different phases.

Abstract: A particulate composition comprises a plurality of particles wherein at least one of the particles comprises at least two different crystalline and/or glass phases, each phase comprising a host lattice and a dopant sensitive to electromagnetic radiation. The different phases simultaneously produce different responses on exposure to photons of the same energy, whereby the output from the particulate composition when exposed to said photons is the sum of the responses from the different phases.

Abstract: A SERS tag comprising a core comprising at least two aggregated particles of a SERS enhancing material wherein the contact point between the particles defines a crevice; and a reporter molecule having a length sufficiently short to fit into the crevice and a conjugated path length which is as large as possible, provided the overall reporter molecule length is maintained sufficiently short to fit into the crevice.

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: An inline spectroscopic reader having a light source, one or more optics heads, a spectrometer and a data processing system in digital communication with the spectrometer detector. The optics heads include transmission optics providing for the illumination of a target with light from the light source and detection optics providing for the collection of light from the target. Typically, the target is moving with respect to the optics head during spectroscopic interrogation. The spectroscopic reader is thus an inline reader well suited to provide spectrum based production or analytical decision making in real time as the target moves along a production or analysis line. Also disclosed are methods including the steps of illuminating a target with light from a light source; collecting light from the target; obtaining a digitized spectrum with a spectrometer; extracting information content from the digitized spectrum; and basing a contemporaneous process decision upon the information content.

Abstract: Wavelength selective particles such as SERS nanotags modified for wavelength selectivity. As used herein, a wavelength selective particle is one which cannot be effectively excited or interrogated at one or more wavelengths where a reporter molecule associated with the particle would normally produce a spectrum. Also disclosed are methods of manufacturing wavelength selective particles and methods of tagging materials or objects with wavelength selective particles.

Abstract: A SERS tag comprising a core comprising at least two aggregated particles of a SERS enhancing material wherein the contact point between the particles defines a crevice; and a reporter molecule having a length sufficiently short to fit into the crevice and a conjugated path length which is as large as possible, provided the overall reporter molecule length is maintained sufficiently short to fit into the crevice.

Abstract: Methods of separating one type of nanoparticle from another type of nanoparticle in a mixture including more than one type of nanoparticle are disclosed. The methods may include suspending a mixture of the various types of nanoparticles in a liquid and modifying a characteristic of the liquid. Thereafter, a force may be applied to the nanoparticles within the mixture causing one type of nanoparticles to separate from another type of nanoparticles. The applied force may be the force of gravity, or it may be an induced force such as a centrifugal force applied with a centrifuge or similar apparatus. Upon the occurrence physical separation, sub-populations of nanoparticles may be removed from the suspension or segregated. Alternatively the methods may include modifying a type of nanoparticle in suspension. Alternative embodiments include nanoparticles modified in suspension to provide for separation from other types of nanoparticles.

Abstract: An optically active particle and a method of manufacturing said particles, plus methods of tagging a material of interest with said particles are disclosed. The particle comprises a surface-enhanced spectroscopy (SES) active core and a SES active reporter associated with the SES core wherein the particle produces a measurable and thermally stable SES spectrum upon optical interrogation. As used in the disclosure, thermally stable may be defined as maintaining a measurable SES spectrum after the particle or any material tagged with the particle has been exposed to a temperature substantially higher than room temperature.

Abstract: Embodiments include a particle comprising a surface enhanced spectroscopy (SES)-active core and a SES-active reporter molecule associated with the SES-active core wherein said particle has a measurable SES spectrum when excited by incident light having a wavelength of at least 1400 nm. Alternative embodiments include methods of manufacturing said particle and methods of tagging a material with said particle. The particle may include an SES-active core which supports plasmon resonance at a wavelength of at least 1400 nm. The particle may comprise an anisotropic core. The particle may include an SES-active reporter molecule which is resonant at one or more wavelengths greater than or equal to 1400 nm.

Abstract: Embodiments include types of programmable surface-enhanced spectroscopy (SES) particles (PSPs), including PSP 200 having a SES-active surface 202 and a programmable reporter 206 associated with the SES surface 202 and methods of fabricating and using same. The programmable reporter 206 provides that the PSP 200 will return a controlled but variable signal in response to spectroscopic interrogation. The spectroscopic signal can be triggered to change externally or the signal may naturally vary over time.

Abstract: A suspendable SERS nanotag. As used herein, a suspendable tag is one which remains suspended in a specific liquid, water for example, for a period of time. Thus, a suspendable tag does not sink to the bottom of a container of the liquid or float to the top of a container of the liquid within the selected time period. A suspendable SERS nanotag may include a metal core, for example, an Au core having a diameter of less than 90 nm. The suspendable SERS nanotag may also include a SERS active reporter molecule associated with the core and a silica containing encapsulant, encapsulating the core and reporter association.

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 catalytic nanotemplate including a freestanding template particle and a director associated with the surface of the freestanding template particle. The free standing template particle may have multiple segments and the director may be associated with one or more of the segments. In instances where multiple segments are present, the segments may be made of different materials or be of the same material in different forms. More than one type of director or no director may be associated with any particular segment.

Abstract: A catalytic nanotemplate including a freestanding template particle and a director associated with the surface of the freestanding template particle. The free standing template particle may have multiple segments and the director may be associated with one or more of the segments. In instances where multiple segments are present, the segments may be made of different materials or be of the same material in different forms. More than one type of director or no director may be associated with any particular segment.