10 results about "Lateral flow test" patented technology

The application discloses a lateral test strip for detecting C-reactive protein and application thereof, and the test strip comprises a bottom plate and a sample pad, a combination pad, a nitrocellulose membrane and a water absorption paper which are sequentially stacked on the bottom plate; the combination pad is loaded with AIE fluorescent microspheres; the AIE fluorescent microspheres are composed of P(St-MMA) microspheres coated with AIE materials after hydrolysis and carboxylation; and anti-C-reactive protein antibodies are connected to the AIE fluorescent microspheres through a covalent bond. The surface coating amount of the AIE fluorescent microspheres is increased by 1.6-2.3 times, and the fluorescence intensity per unit mass is increased by about 40-60%. The increase of the coating amount makes the density of the light-emitting core higher, the overall quantum yield is significantly improved, and the uniformity of the fluorescence signal and the detection sensitivity are enhanced. The characteristics are particularly prominent in the detection of CRP protein in the chromatographic test strip, and the detection limit can be effectively reduced, the T / C signal ratio can be improved, and the reaction time can be shortened.

The present application belongs to the field of analytical chemistry detection, and particularly relates to a nucleic acid lateral flow chromatographic test strip, a preparation method and application thereof, and aims to solve the technical defects of traditional lateral flow test strip, such as single target, low quantitative precision and insufficient sensitivity. The test strip is assembled from a sample pad, a combination pad, a nitrocellulose membrane, a water absorption pad and a PVC bottom plate, the combination pad is loaded with Au nanoparticle modified nucleic acid reporter probe, and the C line probe and the T line probe are fixed on the NC membrane; the test strip is targeted recognition mediated by strand displacement reaction, different types of targets are converted into M-DNA with the same sequence, after exponential amplification of the signal, quantitative detection is completed by using test strip color development combined with sampling and software analysis. The sensitivity can be as low as 0.18 pM for different analytes, and good specificity and stability are still maintained in complex matrix such as serum, and it is suitable for rapid quantitative analysis of multiple types of targets in the scene of instant detection.

The present application belongs to the field of biological detection, and particularly relates to a field visual rapid detection method for citrus Huanglongbing. The present application is based on MIRA-lateral flow test paper, takes the outer membrane protein (OMP) of Asian species of Huanglongbing bacteria of citrus as a target, designs and selects specific primers and probes, and prepares dry powder microspheres together with MIRA reaction enzymes, mixes the field rapid extraction plant DNA lysate, dry powder microspheres and Buffer microspheres in a closed chamber to react, adopts a miniature temperature control device to complete amplification under the condition of 42 DEG C for 20 minutes, and directly realizes visual interpretation of the associated test paper strip. The detection method has no cross reaction with other citrus pathogenic bacteria, the sensitivity test can detect the DNA concentration lower limit of 6.9x10 ‑3 ng / μL, the detection device is small in size and convenient to carry, the whole process does not need professional operation or precise instruments, the detection can be completed within 30 minutes, and the detection method is suitable for rapid detection of citrus Huanglongbing by grass-roots agricultural technicians, planting enterprises and fruit farmers.

This invention discloses a freeze-dried RAA-CRISPR / Cas13a one-pot system and its application for on-site detection of Mycobacterium tuberculosis. The freeze-dried RAA-CRISPR / Cas13a one-pot system includes Cas13a protein and crRNA, or a complex of the two, and a lateral flow test strip for use with it. The crRNA includes an anchoring sequence for binding to the Cas13a protein and a guide sequence for targeting the Mycobacterium tuberculosis target sequence. The Mycobacterium tuberculosis target sequence is shown in SEQ ID No. 1. The lateral flow test strip sequentially includes a sample plate, a gold nanoparticle anti-FITC antibody, a streptavidin line, an antibody capture line, and an absorption plate. The antibody coated on the antibody capture line is goat anti-rabbit IgG. This invention has good sensitivity and specificity, and a simple and rapid detection of Mycobacterium tuberculosis nucleic acid can be achieved by a single-step reaction at room temperature. Moreover, the reaction process does not require opening the cap, solving the problem of aerosol contamination that is prone to occur in two-step detection methods.

The present application relates to the field of agricultural ecological monitoring and molecular diagnosis, and specifically discloses a method for rapidly detecting soil cadmium pollution by using plant genetic markers, which aims to solve the problems of complex pretreatment, dependence on large instruments and inability to reflect biological availability in existing soil cadmium detection, selects the cadmium-specific response gene rb_592991 of the super-hyperaccumulator Bidens pilosa as a target, extracts the total RNA of the Bidens pilosa exposed to the soil to be detected, performs one-pot constant-temperature reaction at 60 DEG C by using RT-LAMP combined with CRISPR / Cas12b system, and realizes naked-eye visual interpretation by using a colloidal gold lateral flow test strip. The detection system of the present application has a minimum detection limit (LOD) of 0.2 mg / L in a water culture environment, has strong anti-interference property, does not require expensive instruments, and can rapidly evaluate the biological availability of soil cadmium in situ, thereby providing a simple, efficient and new strategy for early warning of cadmium pollution in farmland and traditional Chinese medicine production areas.

The application discloses a kind of ratio type SERS-LFIA dual-mode detection platform and its construction and application.The platform includes Au@Raman molecule@Ag core-shell nano probe, lateral flow test strip and portable dual-mode reading instrument.Through 2~6nm thin silver shell coating, probe has colorimetric and SERS enhancement function;With the T / C ratio correction of quality control line as internal reference, batch and matrix interference is effectively eliminated.During detection, HER2 antigen and probe compound are captured by detection line, to realize colorimetric rapid screening and SERS accurate quantification combination.The platform has wide detection range and low detection limit.Clinical verification shows that the results are highly consistent with ELISA and IHC, and can distinguish different expression levels of HER2 antigen.The platform is rapid, low cost and easy to operate, and is suitable for breast cancer instant diagnosis.

This invention discloses a rapid quantitative detection method for Salmonella using LFS-SERS, belonging to the field of food safety technology. The method includes the following steps: S1, lysing the sample to obtain a crude DNA solution; S2, using the crude DNA solution as a template, performing Salmonella-specific LAMP amplification to obtain a biotin-labeled product; S3, mixing dCas9 protein, sgRNA, SERS-labeled gold nanoparticle-probe conjugate, the biotin-labeled product, and a loading buffer solution, incubating at room temperature for 1-5 minutes, performing a colorimetric reaction using a lateral flow test strip, and using a portable Raman spectrometer connected to a smart terminal to detect the T line in the LFS using SERS, thus achieving quantitative detection of Salmonella in the sample. This method is highly specific, sensitive, and stable; the entire detection process can be completed within 40 minutes, and it is low-cost and easy to operate.

Provided is a test device for performing a lateral flow test for testing a presence of a target analyte in a sample fluid. The test device comprises a test substrate, wherein the test substrate includes a plurality of functionalized nanoparticles and one or more nanoscale objects. Each nanoscale object is or comprises a DNA origami.

A method for packaging a lateral flow detection housing (47, 147, 247, 347) and a lateral flow detection test strip (22a, 122a, 222a, 322a), comprising: an elongated first web (14, 114, 214, 314) containing a thermoformable material; thermoforming a plurality of spaced recesses (28, 128a, 228, 328a) in the elongated first web (14, 114, 214, 314); and providing a lateral flow detection test strip (22a, 122a, 222a, 322a). The method involves supplying a lateral flow test strip (a, 122a, 222a, 322a) that is held in a recess (28, 128a, 228, 328a) by attaching a second web (18, 118, 218, 318) to a first web (14, 114, 214, 314), and cutting the attached web to separate the held lateral flow test strip (22a, 122a, 222a, 322a) into packages (47, 147, 247, 347). The elongated second web (118, 318) may comprise a thermoformable material, and the method further includes thermoforming spaced features, such as recesses (128b, 328b), on the elongated second web.

CRISPR diagnostic systems have shown great potential for detecting SARS-CoV-2, but improvements in sensitivity, specificity, and turnaround time are needed. Typically, a gRNA with CRISPR-Cas12a is used to detect the target DNA and activate its collateral activity, which is then used to cleave a reporter probe. Here, we demonstrate that the parallel use of two or three gRNAs accelerates the probe cleavage rate by up to 4.5 times compared to individual gRNAs. This synergistic effect is related to the parallel activation of CRISPR-Cas12a and the individual activity of the gRNAs. This observation led to a system that, using two gRNAs, detected the SARS-CoV-2 RNA gene N at up to 10 viral copies after prior amplification with RT-LAMP.The proof of concept of the system was demonstrated with 100% detection of positive and negative clinical samples in ~25 minutes using the fluorescence plate reader and ~45 minutes for lateral flow test strips.