5results about How to "Reduce background" patented technology

The invention belongs to the technical field of biological medicine micro-nano materials, and particularly relates to a magnetic microsphere with protein nonspecific adsorption resistance for immunodiagnosis as well as a preparation method and application of the magnetic microsphere. The preparation method comprises the following steps: S01, carrying out free radical copolymerization reaction on magnetic microspheres and a cross-linked copolymer material under the action of an initiator to introduce carboxyl to obtain first magnetic microspheres; s02, carrying out covalent coupling on the first magnetic microspheres, micromolecules or polymers with polyamino functional groups and micromolecules or polymers with polycarboxyl functional groups to obtain second magnetic microspheres; S03, adding zwitterions into the reaction system, and obtaining third magnetic microspheres on the basis of the second magnetic microspheres; and S04, adding a functional monomer with a carboxyl group or an epoxy group into the reaction system, and obtaining a final compound microsphere on the basis of the third magnetic microsphere. The composite magnetic microspheres provided by the invention can be used for immunodetection, and have higher signals and lower background.

This invention belongs to the field of fetoglobulin B detection technology, and discloses an immunochromatographic test strip for quantitative detection of fetoglobulin B using quantum dot fluorescent microspheres and its preparation method. The immunochromatographic test strip of this invention includes a sample pad, a release pad, and a nitrocellulose membrane; the release pad is coated with a fetoglobulin B monoclonal antibody labeled with quantum dot fluorescent microspheres and a mouse IgG antibody labeled with quantum dot fluorescent microspheres; the nitrocellulose membrane has a detection line and a control line, the detection line is coated with fetoglobulin B monoclonal antibody, and the control line is coated with goat anti-mouse IgG antibody. The immunochromatographic test strip of this invention reduces the detection time to 9-12 minutes, and the total detection time is only 20 minutes, achieving rapid and accurate quantitative detection of fetoglobulin B. It also features high detection sensitivity, a wide detection range, and simple and rapid operation, which is beneficial for the screening and monitoring of atherosclerotic coronary heart disease.

The invention provides a light-activated chemiluminescence detection reagent composition, a kit, a detection method and a device. The light-excited chemiluminescence detection reagent composition comprises a first reagent and a second reagent, wherein the first reagent comprises a polyantibody A combined with a first marker; the second reagent comprises a light-emitting microsphere, the light-emitting microsphere can react with singlet oxygen to generate a detectable signal, and the surface of the light-emitting microsphere is coated with a monomer antibody B; and the polyantibody A and the monomer antibody B recognize different epitopes of a target molecule to be detected. When the detection reagent composition is used for target molecule detection, the background can be reduced while the positive signal value is not influenced, and the detection accuracy and sensitivity are ensured.

The utility model discloses an ultrahigh vacuum optical fiber feed-through integrated with a light beam focusing function, which comprises a vacuum flange plate, a lens mounting cylinder and an optical fiber head mounting seat, and is characterized in that a light beam is guided into an ultrahigh vacuum cavity through an optical fiber and is directly input through an optical fiber slot on the flange plate; the stability of an optical path can be well guaranteed, and meanwhile, great convenience is brought to equipment movement; in addition, the required laser beam enters the cavity through the optical fiber port, so that excessive light exposure windows do not exist, and the background brought by spatial light can be greatly reduced. A collimating lens group is further arranged in the optical fiber head mounting seat, a focusing lens is arranged in the lens mounting barrel, a position adjusting mechanism is further arranged, and the diameter of a light spot can be changed by adjusting the distance between the collimating lens group and the focusing lens.

The online alpha particle detector of this invention integrates a ZnS(Ag) detector and a PIPS (ion-implanted passivated silicon) detector. Both ZnS(Ag) and PIPS are insensitive to ambient gamma rays, allowing the device to achieve low background and detection limits without additional shielding. ZnS(Ag) is also insensitive to beta rays; with proper threshold setting, the interference of beta rays on ZnS(Ag) is negligible. For PIPS, the energy spectrum of beta rays is concentrated in the low-energy region; interference from beta rays can be eliminated through energy spectrum analysis algorithms or by increasing the lower limit of the energy spectrum threshold. Thus, the influence of beta and gamma rays on the combined detector's measurement of alpha particles is greatly reduced, improving the detection accuracy of alpha particles. The ZnS(Ag) detector is coupled with multiple PMTs, further ensuring detection efficiency. The detection window structure, thanks to its unique design, is easy to replace, and the window materials—aluminum foil, titanium foil, and gold foil—are flexibly adaptable. The detector is resistant to strong acids and alkalis and corrosion, enabling a wider range of applications.