Sensor devices for quantifying luminescent targets are described herein. An example device comprises a light source for exciting the targets, thus generating luminescence signals and a detector for detecting these signals, resulting in a detected signal which comprises a desired signal originating from the targets and a background signal. It moreover comprises a bleaching device for bleaching of at least part of the sources generating the background signal and a processor configured to trigger the bleaching device to start bleaching, and to trigger the light source for exciting the remaining luminescent targets which are not bleached, and to trigger the detector for detecting the luminescence signal of the remaining luminescent targets, so as to generate a measurement signal representative for the quantification of the luminescent targets.

A method is provided for verifying the authenticity of an article which bears a security mark. The method includes irradiating the security mark with a time-varying light source, ascertaining at least one portion of the emissions spectrum of the irradiated security mark with at least one photodetector, determining the photoluminescence lifetime of the security mark by monitoring the time or frequency response of the photodetector, and verifying the authenticity of the article only if the security mark exhibits a photoluminescence which has a lifetime that falls within the range of appropriate values for each portion of the photoluminescence spectrum for which the photoluminescence lifetime of said security mark was ascertained.

Some embodiments described herein relate to a sensor that includes a first a first polymer-luminescent sensing compound configured to produce a first luminescent signal in the presence of a first analyte and a second polymer-luminescent sensing compound configured to produce a second luminescent signal in the presence of a second analyte. The second luminescent signal can have a luminescent lifetime that is at least 1.1 times greater than a luminescent lifetime of the first luminescent signal. Such temporally differences in signal can be used to deconvolute the first luminescent signal from the second luminescent signal even when, for example, the first luminescent signal and the second luminescent signal have the same or a similar emission spectrum.

A method is provided for verifying the authenticity of an article which bears a security mark. The method includes irradiating the security mark with a time-varying light source, ascertaining at least one portion of the emissions spectrum of the irradiated security mark with at least one photodetector, determining the photoluminescence lifetime of the security mark by monitoring the time or frequency response of the photodetector, and verifying the authenticity of the article only if the security mark exhibits a photoluminescence which has a lifetime that falls within the range of appropriate values for each portion of the photoluminescence spectrum for which the photoluminescence lifetime of said security mark was ascertained.

Some embodiments described herein relate to a sensor that includes a first a first polymer-luminescent sensing compound configured to produce a first luminescent signal in the presence of a first analyte and a second polymer-luminescent sensing compound configured to produce a second luminescent signal in the presence of a second analyte. The second luminescent signal can have a luminescent lifetime that is at least 1.1 times greater than a luminescent lifetime of the first luminescent signal. Such temporally differences in signal can be used to deconvolute the first luminescent signal from the second luminescent signal even when, for example, the first luminescent signal and the second luminescent signal have the same or a similar emission spectrum.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

The present invention relates to a method for detecting an amyloid oligomer which includes a test sample and thioflavin T are brought into contact with each other, fluorescence of the thioflavin T is measured to obtain time-resolved fluorescence spectra, the time-resolved fluorescence spectrum of time period t1 to t2 and the time-resolved fluorescence spectrum of time period t3 to t4 are respectively normalized to obtain normalized spectra (t1<t2t3 <t4), and determination is made to confirm the presence or absence of an amyloid oligomer in the test sample on the basis of the two normalized spectra, and shifting of the normalized spectrum of time period t3 to t4 towards the low wavelength side in comparison to the normalized spectrum of time period t1 to t2 indicates the presence of an amyloid oligomer in the test sample.

Some embodiments described herein relate to a sensor that includes a first a first polymer-luminescent sensing compound configured to produce a first luminescent signal in the presence of a first analyte and a second polymer-luminescent sensing compound configured to produce a second luminescent signal in the presence of a second analyte. The second luminescent signal can have a luminescent lifetime that is at least 1.1 times greater than a luminescent lifetime of the first luminescent signal. Such temporally differences in signal can be used to deconvolute the first luminescent signal from the second luminescent signal even when, for example, the first luminescent signal and the second luminescent signal have the same or a similar emission spectrum.

A method is provided for verifying the authenticity of an article which bears a security mark. The method includes irradiating the security mark with a time-varying light source, ascertaining at least one portion of the emissions spectrum of the irradiated security mark with at least one photodetector, determining the photoluminescence lifetime of the security mark by monitoring the time or frequency response of the photodetector, and verifying the authenticity of the article only if the security mark exhibits a photoluminescence which has a lifetime that falls within the range of appropriate values for each portion of the photoluminescence spectrum for which the photoluminescence lifetime of said security mark was ascertained.

A time-resolved fluorescence imaging (TRFI) system that images a target medium without lifetime fitting. Instead of extracting the lifetime precisely, the system images the fluorophore distribution to allow for a simple and accurate method to obtain the fluorescence image without lifetime-extraction for time-resolved fluorescence imaging. An illumination source circuit for TRFI is also disclosed that shapes the excitation pulse. In one embodiment, the illumination source comprises an LED and stub line configured for generating a linear decay profile.