70results about "Material analysis using immobilised reagents" patented technology

This invention relates generally to devices and methods for performing optical and electrochemical assays and, more particularly, to devices having optical and electrochemical detectors and to methods of performing optical and electrochemical assays using such devices. The present invention is particularly useful for performing immunoassays and / or electrochemical assays at the point-of-care.

This invention relates generally to devices and methods for performing optical and electrochemical assays and, more particularly, to devices having optical and electrochemical detectors and to methods of performing optical and electrochemical assays using such devices. The present invention is particularly useful for performing immunoassays and / or electrochemical assays at the point-of-care.

Methods and devices for the measurement of molecular binding interactions. Preferred embodiments provide real-time measurements of kinetic binding and disassociation of molecules including binding and disassociation of protein molecules with other protein molecules and with other molecules. In preferred embodiments ligands are immobilized within pores of a porous silicon interaction region produced in a silicon substrate, after which analytes suspended in a fluid are flowed over the porous silicon region. Binding reactions occur when analyte molecules diffuse closely enough to the ligands to become bound. Preferably the binding and subsequent disassociation reactions are observed utilizing a white light source and thin film interference techniques with spectrometers arranged to detect changes in indices of refraction in the region where the binding and disassociation reactions occur. In preferred embodiments both ligands and analytes are delivered by computer controlled robotic fluid flow control techniques to the porous silicon interaction regions through microfluidic flow channels.

A phase contrast quadrature interferometric method for determining the presence or absence of a target analyte in a sample. The method comprises using a laser beam having a wavelength λ and a waist wo to probe at least a portion of a substrate having a reflecting surface that has been exposed to the sample. The reflecting surface includes at least a first region having a layer of recognition molecules specific to the target analyte and a second region that does not include a layer of recognition molecules specific to the target analyte. The method further comprises measuring a time dependent intensity on a photodetector of a substantially only first quadrature at one of a pair of quadrature angles ⊖q of a reflected diffraction signal of the probe beam while probing the first region and the second region. An apparatus for phase-contrast quadrature interferometric detection of the presence or absence of a target molecule on a planar array, comprises a laser source for generating a probe beam. The apparatus includes a platform for receiving the planar array and a first optical train for directing the probe beam at the platform in a substantially surface normal manner. The apparatus also includes an objective lens having a first side and a second side and having a focal length, the objective lens being offset on the first side of the lens from the platform by a first distance approximately equal to the focal length. The apparatus further includes split photodetector means for measuring a first quadrature and a second quadrature in a signal resulting from reflection of the probe laser beam.

A change in mass of a microbridge in a mass sensor can be sensed by applying a time-varying amplitude modulated electrostatic force to excite the microbridge into resonance at the frequency of amplitude modulation. An optical energy is then transmitted at a wavelength close to a resonant wavelength of a Fabry-Perot microcavity, which is formed by etching a movable reflective mirror into a region of the microbridge and by etching a fixed reflective minor in a region spaced apart from the microbridge. The two mirrors are interconnected by an optical waveguide. The movable mirror and fixed mirror reflect the optical energy to a receiver, and a change in the Fabry-Perot microcavity's reflectivity is interferometrically determined. The change in reflectivity indicates a change in the microbridge's resonant frequency due to increased mass of the microbridge resulting from sorption of a target chemical by a layer of chemoselective material deposited on the microbridge.

The invention discloses a biosensor based on a Ti3C2 two-dimensional metal carbide catalyzed luminol electrochemiluminescence probe and a preparation method thereof. The biosensor based comprises a probe and a biosensor electrode, wherein the probe comprises nanosheets Ti3C2 MXenes, joint molecules and biometric molecules 1; the nanosheets Ti3C2 MXenes are connected with the joint molecules through electrostatic adsorption; the joint molecules are connected with the biometric molecules 1 through amide groups; the joint molecules contain primary or secondary amine groups; the joint molecules can be positively charged after being dissolved in water; the biometric molecules 1 are single-stranded DNA sequences 1 having carboxyl groups at the 5' ends; the single-stranded DNA sequences 1 can recognize CD63 protein on exosomes. The invention finds that Ti3C2 MXenes can improve the electrochemiluminescence of luminol for the first time, and by virtue of the property, the Ti3C2 MXenes is prepared into the probe and then the biosensor is prepared.

The present invention is directed to a luminescent immunoassay method for detecting an analyte in a liquid sample with high sensitivity. The invention provides a unique combination of (i) using a probe having a small sensing surface area for binding analyte molecules, (ii) using a high molecular weight branched polymer conjugated with multiple binding molecules and multiple luminescent labels, and (iii) cycling the probe having immunocomplex formed back to the reagent vessel and amplification vessel 1-10 times and repeating the reaction with the reagent and the amplification polymer, to improve the sensitivity of detection level. For each cycling, the luminescent signal is increased significantly over the noise.

A symmetric or asymmetric multilayer structure based on the technique of surface plasmon resonance (SPR) has been applied for modulation of resonant angle and wavelength. The fabrication of this invention can have nanoscale thin film layers up to several hundreds, while each layer has its own material of a high or low refractive index value, and the total layers in a thickness of tens to hundreds nanometers are grown in this single structure. This invention is intended for optimizing the scanning of mechanism by modulating SPR resonant angle and wavelength, and for developing the prospect of portable instruments.

Techniques for colorimetric based test strip analysis and reader system are provided. In one aspect, a method of test strip analysis includes: illuminating a test strip wetted with a sample with select spectrums of light, wherein the test strip includes test pads that are configured to change color in the presence of an analyte in the sample; obtaining at least one digital image of the test strip; and analyzing color intensity from the at least one digital image against calibration curves to determine an analyte concentration in the sample with correction for one or more interference substances in the sample that affect the color intensity. A calibration method and a reader device are also provided.

The present invention provides an immune detection kit, which is mainly composed of a release reagent plate and a reaction reagent plate. The immune detection kit is different from lateral flow immunoassay test paper in the prior art, when the immune detection kit is used for competitive or sandwich type lateral flow immunoassay of a sample to be tested, first, the release reagent plate must be placed into a sample liquid for release into the sample liquid and further mutual combination with a target detection matter in the sample liquid of a marker-bonded antibody (or drug) which is carried by the release reagent plate; and finally the reaction reagent plate is placed into the sample liquid, so that the sample liquid and an antibody which is carried by a test line on the reaction reagent plate compete or combine with each other, and whether a test result is positive or negative can be judged by whether the test line shows color or not.

A testing device for identifying an antigen or antibody within a biofluid sample including: a substrate having a hydrophilic surface thereon; the surface including a collection zone, and at least one detection zone extending therefrom; wherein the biofluid sample can be mixed with a specific antigen or antibody, and deposited on the collection zone and transferred by capillary action to the detection zone; the antigen or antibody in the biofluid sample reacting with an appropriate said antibody or antigen thereby resulting in a visual indication within the detection zone.