68 results about "Immunomagnetic separation" patented technology

Methods are provided for detecting, separating, isolating and quantifying contaminants in starting materials by separating the contaminant from the starting material using a bead coupled to an affinity moiety and quantum dot-labeling the contaminant. The contaminant is detected by the characteristic emission spectrum of the quantum dot. Also, competitive binding methods are provided wherein the starting material and a control material are contacted with a quantum dot coupled to an affinity moiety capable of binding the contaminant and a competitor complex. A decrease in the intensity of the characteristic emission spectrum of the quantum dot associated with the competitor complex from the starting material as compared to that of the control material is indicative of the presence of the contaminant in the starting material.

The invention is directed to a method for detecting low concentrations of bacteria in liquid solution that may or may not be complex liquid solutions. In one embodiment, immunomagnetic separation (IMS) is used to separate target bacterium that may be in a liquid mixture from other constituents in the mixture. A low concentration of a bacteriophage for the target bacteria is subsequently used to infect target bacterial cells that have been captured using the IMS technique. If at least a certain concentration of target bacterium are present, the bacteriophage will multiply to a point that is detectable. Matrix assisted laser desorption ionization / time-of-flight-mass spectrometry (MALDI / TOF-MS) is then used to produce a mass spectrum that is analyzed to determine if one or more proteins associated with the bacteriophage are present, thereby indirectly indicating that target bacterium were present in the liquid mixture.

The invention discloses a method of detecting ochratoxin A in cereals by means of a nano antibody and immunomagnetic separation. The method includes the steps of: 1) combining anti-OTA nano antibody with nano immunomagnetic beads to prepare IMB, and enriching the OTA in the cereals by means of the IMB to prepare a pretreated sample; 2) with dot immunization method, immobilizing an OTA-OVA detection antigen on a PVDF film, wherein the immunomagnetic beads are subjected to an immune-reaction in the form of antibody marker, the OTA-OVA and the to-be-tested substance, OTA, are combined with the antibody competitively so as to determine whether the immunomagnetic beads are aggregated on the PVDF film or not, thereby obtaining a detection result. The method achieves simple and quick qualitative detection. An operator can read the result just by naked eyes without any analysis instrument. Furthermore, the method can be used for developing a novel quick and visible detection card for specially detecting the OTA in the cereals.

The invention provides a rapid detection method for mercury in a liquid biological sample based on magnetic separation and quantum dots (QDs) marking. The method comprises the steps: (1) preparing mercury-resistant monoclonal antibodies; (2) coupling the mercury-resistant monoclonal antibodies with magnetic nanobeads through covalent bonds to prepare mercury-resistant immunomagnetic nanobeadd; and (3) adding a difunctional chelating agent, bovine serum albumin (BSA) and triethylamine (TEA) into the liquid biological sample to incubate, then, adding the mercury-resistant immunomagnetic nanobeads to sufficiently mix, next, carrying out magnetic separation, and adding biotinylated BSA antibodies and streptavidinylated QDs into a sediment, and carrying out fluorescence detection by using a fluorescence microplate, wherein the sediment is obtained through magnetic separation. The invention also provides a rapid detection kit for mercury in a liquid biological sample.

The present invention relates to methods and systems for labeling, isolating, detecting, and / or enumerating a statistically significant number of biological cells, or other biological analytes of interest, present in a complex matrix sample. The isolation of a biological target of interest from a sample mixture is done by immunomagnetic separation. Upon introduction of the sample within an imaging chamber, the capture complex (biological target-magnetic capture agent) will be attracted by the magnetic field and will lay on the surface of the chamber in the focal plane of the imaging system.

The invention relates to a method for enriching Cryptosporidium parvum oocysts and Giardia Lamblia sporocysts in water. The method comprises the following steps: adding an inorganic metal salt coagulant into a bulk water sample, stirring, coagulating, precipitating, collecting precipitate alumen ustum in a small-volume container, adding acidic solution into the small-volume container to dissolve the alumen ustum, centrifuging, removing supernate and thus, enriching the Cryptosporidium parvum oocysts and Giardia Lamblia sporocysts in water. In the invention, the problems of low Cryptosporidium parvum oocyst and Giardia Lamblia sporocyst enrichment rate, instability, high operation requirement and expensive filtering equipment and consumable items of the conventional method for enriching Cryptosporidium parvum oocysts and Giardia Lamblia sporocysts. The method does not need expensive apparatus and equipment and medicines and greatly reduce capital investment. The method is simple in operation, easy to master, time-saving and labor-saving, reduces cost of enrichment of Cryptosporidium parvum oocysts and Giardia Lamblia sporocysts in water, improves enrichment efficiency and is a novel method which clears the preliminary work for subsequent steps of immunomagnetic separation, immunofluorescence label microscope counting, polymerase chain reaction (PCR) qualitative detection, nano probe gene chip detection and Real-time PCR quantitative detection and the like.

The invention discloses a microbe concentration detection method based on immunomagnetic separation and biological catalysis. The method comprises the following steps: separating and enriching target microbes through a first bio-recognition element modified immunomagnetic element to improve the concentration and the purity of the target microbes; simultaneously modifying a nano-element with a second bio-recognition element and a predetermined enzyme, introducing an enzyme for catalyzing a biological reaction to a detection system in a sandwich manner, and changing the pH value of a catalysis solution by using the predetermined enzyme catalyzed biological reaction; and adding a pH indicator, and determining the content of the target microbes in the sample to be detected according to the color change of the pH indicator. The method integrates the purification and enrichment characteristics of immunomagnetic separation, the catalysis amplification characteristic of biological catalysis and the simple determination characteristic of the pH indicator, and also has the advantages of effective improvement of the detection sensitivity, shortening of the detection time, simplification of the detection process, and reduction of the detection cost.

The invention discloses a method of enrichment separation of Campylobacter jejuni, provides a better basic for follow-up study of target bacteria, and relates to the field of biology technology. The method comprises steps of: covalently coupling broom molecules and antibodies, coating antibody-modified broom molecules with long-chain biotin molecules, capturing target bacteria in a sample solution via broom molecules that are modified by the antibodies and the long-chain biotin molecules, identifying streptavidin-modified nano-magnetic-beads and coupling with long-chain biotinylated broom molecules in the sample solution, separating and re-suspending the captured bacteria. Because the re-suspending solution can be used for follow-up analyses directly, the method provide by the invention is even more suitable for magnetic separation of bacteria in complex matrixes compared with conventional magnetic separation of bacteria, and rises the separating efficiency of target bacteria in samples.