The present disclosure provides an anti-biotin antibody, and provides an amino acid sequence encoding the CDRs of the antibody. Studies have shown that the antibody only reacts with a biotin conjugate or derivative, and does not react with free biotin. The present disclosure further provides applications of the antibody in, including but not limited to, ELISA, cell capture, sorting and enrichment, western blotting, flow cytometry, immunocytofluorescent staining, and immunohistochemistry. The anti-biotin antibody conjugated immunomagnetic beads can specifically and directly recognize a biotin labeled antigen, and do not bind to free biotin which is often presented in clinical samples and culture media. In addition, the anti-biotin antibody-conjugated magnetic beads or anti-biotin antibody-fluorescein provide an ideal solution for the isolation of specific cells, and can even enrich and separate target cells from samples rich in debris or other rare biological materials.

The present disclosure provides an anti-biotin antibody, and provides an amino acid sequence encoding the CDRs of the antibody. Studies have shown that the antibody only reacts with a biotin conjugate or derivative, and does not react with free biotin. The present disclosure further provides applications of the antibody in, including but not limited to, ELISA, cell capture, sorting and enrichment, western blotting, flow cytometry, immunocytofluorescent staining, and immunohistochemistry. The anti-biotin antibody conjugated immunomagnetic beads can specifically and directly recognize a biotin labeled antigen, and do not bind to free biotin which is often presented in clinical samples and culture media. In addition, the anti-biotin antibody-conjugated magnetic beads or anti-biotin antibody-fluorescein provide an ideal solution for the isolation of specific cells, and can even enrich and separate target cells from samples rich in debris or other rare biological materials.

The present invention provides a novel method for determining a long-chain non-coding ribonucleic acid interaction protein. The present invention provides a fusion protein formed by BASU and dCasRx, a mammalian expression vector for expressing said fusion protein. The method for determining the lncRNA interaction protein according to the present invention comprises: co-transfecting a mammalian expression vector that expresses the fusion protein and a gRNA that specifically targets the target lncRNA into target cells, thereby BASU specifically biotin-labeling effector proteins nearby; isolating the biotinylated proteins by using a streptavidin affinity coupled magnetic bead and then eluting, and digesting by trypsin and quantitatively analyzing by a label-free mass spectrometry. The present invention can highly credibly determine the proteins that interact with lncRNA.

The present invention relates to a plasmonic biosensor system. The system includes a nano-hole array device comprising at least one nano-hole array (NHA) including at least one or a plurality of nano holes (NH), an image sensor (A3) for capturing light provided by a light source (A1) and transmitted through the nano-hole array (NHA), and at least one or a plurality of nano-particles (NP) configured to be received by the nano-holes (NH) of the nano-hole array (NHA).

The present invention relates to modified streptavidin molecules that are resistant to cleavage by Lys-C or other proteases. These modified streptavidin molecules can be produced by chemical modification of natural streptavidin, by chemical synthesis or by genetic engineering. The invention also relates to nucleic acid molecules encoding these modified streptavidin molecules, to vectors comprising such nucleic acid molecules, and to cells comprising such nucleic acid molecules or vectors. The invention further relates to solid supports and kits comprising the modified streptavidin molecules. The invention also relates to the use of such modified streptavidin molecules or such solid supports for the capture/immobilization of proteins, peptides, oligonucleotides (e.g. aptamers), polynucleotides (e.g. DNA, RNA, or PNA), lipids, (poly) saccharides, carbohydrates, metabolites, drugs and small molecules, natural and synthetic molecules and to the use of these modified streptavidin molecules or these solid supports in mass spectrometry for the identification of proteins that interact with aforementioned (bio)molecules. The invention further relates to a method for reducing background in mass spectrometry by employing the modified streptavidin molecules.

The present invention relates to a plasmonic biosensor system. The system includes a nano-hole array device comprising at least one nano-hole array (NHA) including at least one or a plurality of nano holes (NH), an image sensor (A3) for capturing light provided by a light source (A1) and transmitted through the nano-hole array (NHA), and at least one or a plurality of nano-particles (NP) configured to be received by the nano-holes (NH) of the nano-hole array (NHA).

The present disclosure relates to method of detecting proteins proximal to a target protein using fusion proteins which include: a glycan binding component linked to a mutant E. coli biotin ligase BirA, the glycan binding component capable of specific binding to a glycosylation post-translational modification of a target protein and the mutant E. coli biotin ligase BirA having enzymatic activity to ligate biotin to proteins proximal to the target protein. Such methods include contacting a living cell with the fusion protein under compatible biological conditions, whereby the fusion protein specifically binds to a glycosylation post-translational modification of a target protein of the cell; providing biotin to the living cell, whereby the mutant E. coli biotin ligase BirA ligates biotin to proteins proximal to the target protein; and detecting the biotinylated proteins, thereby detecting proteins proximal to the target protein.

Methods, apparatus and compositions for separating a desired or undesired population or subpopulation from a biological sample are disclosed herein. The selection procedure is based on ferromagnetic, dense particles in a preferred size range from about 0.8 to about 1.2 microns. Specific binding agents are bound to the particles that recognize and bind to specific molecules on the targeted population or subpopulation, and the particles are mixed with the sample in such a way as to promote movement of the particles relative to the sample, promoting binding to the targeted population or subpopulation without non-specifically binding to non-targeted populations in the sample. Because of the large particle density, the bound population is separated from the fluid sample by gravity. Alternatively, the sample, including the bound, targeted population, is placed in a magnetic field such that the particles separate from the sample by evenly distributing over the vessel wall thus limiting non-specific trapping of the non-targeted population.

Disclosed are methods of screening a library of molecules to identify or select one or more molecules which selectively bind to a fused protein, or fragment thereof. The fused protein comprises a moiety and a protein selected from a group consisting of flavivirus structural and non-structural (NS) proteins. The method comprises contacting the library of molecules with the fused protein and detecting binding of one or more molecules to the fused protein.

A proximity detection method is described that utilizes enzymatic biotinylation to detect targets in a sample, particularly formalin fixed paraffin embedded samples using automated staining platforms. One disclosed embodiment comprises contacting the sample with a first conjugate comprising a biotin ligase and a first specific binding moiety that binds proximally to the first target; contacting the sample with a second conjugate comprising a biotin ligase substrate and a second specific binding moiety that binds proximally to the second target; subjecting the sample to conditions that allow biotinylation of the biotin ligase substrate by the biotin ligase when the first target and the second target have a proximal arrangement; and detecting biotinylation of the biotin ligase substrate. The conditions that allow biotinylation of the substrate include addition of biotin and ATP. The method also may comprise contacting the sample with a streptavidin-enzyme conjugate. Signal amplification also can be used.