235 results about "Affitin" patented technology

The invention relates to an HPV16 type E6 oncoprotein monoclonal antibody as well as a preparation method and application thereof. The monoclonal antibody specifically bound with the HPV16E6 recombinant antigen is obtained through screening, the monoclonal antibody is applied to a biotin-avidin amplification ELISA system, the E6 oncoprotein of HPV16 can be specifically detected, the sensitivity is 100 pg / mL, the monoclonal antibody does not intersect with oncoprotein of other high-risk HPV, and the E6 oncoprotein of HPV16 can be specifically detected. High specificity and sensitivity are shown for cervical exfoliated cell sample detection of normal people, CIN3 people and cervical cancer people, and the method can be applied to early screening of cervical cancer in the future; compared with traditional exfoliative cytology examination, the method is faster and more accurate, meanwhile, the risk of false positive and misdiagnosis caused by too high sensitivity of nucleic acid detection can be avoided, and the method has very high application value.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody 4F6 for HPV16 type E7 protein detection and application. The heavy chain variable region CDR sequences and the light chain variable region CDR sequences of the antibody are SEQ ID NO.1-3 and SEQ ID NO.4-6 respectively, and the antibody can be specifically combined with HPV16 type E7 protein without cross reaction. A double-antibody sandwich ELISA detection system constructed based on the antibody is combined with a biotin-avidin amplification technology, the sensitivity reaches 100 pg / mL, and the antibody is suitable for rapid detection of the HPV16 type E7 protein in a cervical exfoliated cell sample. The invention further provides the HPV16 type E7 recombinant protein which is obtained through prokaryotic expression and has immunocompetence, and the HPV16 type E7 recombinant protein is applied to antibody screening and detection. Compared with nucleic acid detection, the method has a lower false positive rate, can be used for early screening of cervical cancer and precancerous lesions, and has a good application prospect.

The present invention belongs to the field of biological detection technology, specifically relating to a monoclonal antibody combination for detecting HPV18 E7 protein and its application. This combination consists of monoclonal antibodies 5F8 and 6G6, wherein the heavy and light chain variable regions of 5F8 and 6G6, respectively, contain specific complementarity-determining region sequences (as shown in SEQ ID NOs. 1 to 12), conferring high specificity for HPV18 E7 protein. Verification using a double-antibody sandwich ELISA and a biotin-avidin amplification system demonstrated that this antibody combination specifically recognizes HPV18 E7 protein, exhibits no cross-reactivity with other high-risk HPV oncoproteins, and exhibits a detection sensitivity of 1 ng / mL. This combination can be used to construct detection systems such as ELISA kits and immunochromatographic test strips, suitable for rapid screening of HPV18 E7 protein in cervical exfoliated cell samples.

The invention relates to the technical field of biological detection, in particular to a monoclonal antibody combination for HPV18 type E6 protein detection and application. The provided combination is composed of 5G3 and 2C7, and the amino acid sequences of complementary determining regions of variable regions of a heavy chain and a light chain of the combination are clear and are respectively shown as SEQ ID NO.1-12. The antibody combination has high specificity and sensitivity, the lowest detection limit can reach 100 pg / ml, and cross reaction with other HPV subtypes is avoided. According to a double-antibody sandwich ELISA and biotin-avidin amplification detection system constructed based on the combination, the signal intensity and the detection accuracy are remarkably improved, and the combination is suitable for rapid detection of the HPV18 type E6 protein in a cervical exfoliated cell sample and has application value in early diagnosis of cervical cancer, risk stratification, vaccine research and development and curative effect evaluation.

The invention relates to the technical field of in-vitro diagnostic reagent chemiluminescence detection, in particular to a Christmas liquefied carbohydrate chain antigen chemiluminescence detection kit and a preparation method thereof. The chemiluminescence detection kit comprises the following components: a KL-6 calibrator, an amino magnetic bead coupled KL-6 monoclonal antibody, an alkaline phosphatase labeled KL-6 monoclonal antibody, an AMPPD rapid chemiluminescence substrate solution and a cleaning solution, and the chemiluminescence detection kit prepared from the components is simple in detection process, easy to operate, high in automation degree and high in detection sensitivity. The kit is high in sensitivity, good in specificity and good in stability, a result can be automatically obtained within 12.5 min, the requirement for clinical auxiliary diagnosis of interstitial lung diseases can be met, and the problem that in the prior art, a chemiluminescence detection kit prepared by adopting an acridinium ester magnetic particle chemiluminescence immunoassay method or a biotin-streptavidin detection system is poor in specificity and high in sensitivity is solved. The technical problems of low marking efficiency, high manufacturing cost and poor detection result reliability in the prior art are solved.

The invention belongs to the technical field of gene engineering, and particularly relates to a biotin ligase mutant as well as a coding gene, an expression vector, a recombinant cell and application thereof. The amino acid sequence of the biotin ligase mutant is as shown in SEQ ID NO. 2. The biotin ligase (Bar A) mutant provided by the invention can be efficiently expressed in eukaryotes, the expression level of the biotin ligase (Bar A) mutant is obviously improved in mammalian cells compared with a wild type, and the biotin ligase (Bar A) mutant has good catalytic activity after expression, can effectively catalyze biotinylation of protein containing a biotin receptor sequence, and has good application prospects. The method has a wide application prospect in the fields of biotinylated protein preparation, and protein labeling, positioning, immunodetection, affinity purification, function research and the like based on a biotin-avidin system (BAS).

The invention discloses a decafluorobiphenyl-based Tat47-57 binding peptide, the amino acid sequence of the binding peptide is shown as SEQ ID NO.1 or SEQ ID NO.2, the fourth amino acid and the eighth amino acid of the SEQ ID NO.1 are bound through decafluorobiphenyl, and the fifth amino acid and the twelfth amino acid of the SEQ ID NO.2 are bound through decafluorobiphenyl. In particular, the decafluorobiphenyl-based Tat47-57 binding peptides (P3 and P6) are efficient CPPs, capable of delivering a variety of cargo molecules into the cytoplasm of mammalian cells. Meanwhile, decafluorobiphenyl cyclization plays a key role in cellular uptake and endosome escape. The two peptides P3 and P6 show remarkable cell permeability, and are speculated to enter cells through gridding protein dependent endocytosis. They also show efficient endosome escape ability, and have successfully applied P3 and P6 as CPPs to deliver phospholipid peptides and avidin.

The present invention relates to the field of biological detection technology, and in particular to a monoclonal antibody combination and application for the detection of HPV18 type E6 protein. The provided combination consists of 5G3 and 2C7, and the amino acid sequences of the complementary determining regions of the heavy chain and light chain variable regions are clear, as shown in SEQ ID NO.1-12, respectively. The antibody combination has high specificity and sensitivity, with a minimum detection limit of up to 100 pg / ml, and does not cross-react with other HPV subtypes. The double-antibody sandwich ELISA and biotin-avidin amplification detection system constructed based on the combination significantly improves the signal intensity and detection accuracy, is suitable for the rapid detection of HPV18 type E6 protein in cervical exfoliated cell samples, and has application value in the early diagnosis of cervical cancer, risk stratification, vaccine development and efficacy evaluation.

The invention relates to a second antibody for resisting mouse IgG and rabbit IgG as well as a preparation method and application of the second antibody. The second antibody of the anti-mouse IgG and the rabbit IgG sequentially comprises an anti-mouse IgG nano antibody, a biotin fixed-point binding peptide fragment and an anti-rabbit IgG nano antibody from an amino terminal to a carboxyl terminal. According to the design of the second antibody of the anti-mouse IgG and rabbit IgG with a brand-new structure and the preparation method, high-efficiency expression is realized, the second antibody of the anti-mouse IgG and rabbit IgG capable of realizing fixed-point biotinylation is obtained, the second antibody can be further subjected to various modification reformation based on a biotin-streptavidin bridge, the preparation method of the second antibody of the polymerase labeled anti-mouse IgG and rabbit IgG is further developed, and the application of the second antibody of the polymerase labeled anti-mouse IgG and rabbit IgG is expanded. According to the method, the polymerase-labeled mouse-rabbit universal secondary antibody with similar affinity to mouse IgG and rabbit IgG is obtained, the preparation period of the secondary antibody can be shortened, the preparation process of the secondary antibody is simplified, the stability between batches is improved, and meanwhile, the dependence on experimental animals is reduced.

The invention discloses a chemiluminescence heparin binding protein kit and a determination method thereof. The kit comprises reagent components of a reagent R1, a reagent R2 and a reagent R3, as well as a matched calibrator, a matched quality control product, a matched pre-excitation liquid, a matched excitation liquid and a matched cleaning liquid, wherein the reagent R1 contains magnetic particles coated with streptavidin, and the reagent R2 and the reagent R3 are respectively monoclonal antibodies which are labeled by acridinium ester and biotin and are used for recognizing different epitopes of human HBP. The kit shows better sensitivity, wider detection range and high specificity, and can effectively reduce potential endogenous and exogenous interference in clinical samples of potential interference people.

The invention relates to a kit for detecting granzyme B as well as a preparation method and application of the kit. The kit for detecting granzyme B comprises a magnetic microsphere working solution, a detection antibody and streptavidin labeled phycoerythrin. The invention also provides a preparation method of the kit for detecting granzyme B. The preparation method comprises the following steps: coupling a granzyme B antibody by using a magnetic fluorescence coding microsphere to obtain a granzyme B antibody-coupled magnetic fluorescence coding microsphere; labeling the granzyme B detection antibody with biotin to obtain a detection antibody; the preparation method comprises the following steps: mixing granzyme B antibody coupled magnetic fluorescence coded microspheres, a PBS buffer solution, a stabilizer, a preservative, a surfactant and a blocking agent to obtain a magnetic microsphere working solution, and assembling the magnetic microsphere working solution with a detection antibody and streptavidin labeled phycoerythrin to obtain the kit. The invention also provides a kit for detecting serum granzyme B. The invention solves the problem of poor detection reliability caused by false positive results and cross reaction in the existing serum granzyme B detection method.

The invention discloses a preparation method of antibacterial dual-oxygen-supply manganese-doped carbon dot-oxygen-carrying microbubbles, and belongs to the field of preparation of medical configuration products, and the preparation method comprises the following steps: attaching biotinylated manganese-doped carbon dots to oxygen-carrying microbubbles by using biotin-avidin connection to prepare micron-level manganese-doped carbon dot-oxygen-carrying microbubbles; the size of the micron-level manganese-doped carbon dot-oxygen-carrying microbubble is 1000-2500nm. The antibacterial dual-oxygen-supply manganese-doped carbon dot-oxygen-carrying microbubble prepared by the invention has the advantages of simple synthesis, clear structure, adjustable size and the like, and the material preparation method is simple, mild in reaction condition and suitable for large-scale production; manganese-doped carbon dot-oxygen-carrying microbubbles provide dual oxygen supply to enhance the sonodynamic therapy effect, so that efficient antibacterial activity is achieved, angiogenesis is promoted, wound healing is accelerated, and the method is a promising wound healing therapy method.

The invention provides an immobilized carrier based on bovine serum albumin-biotin as well as a preparation method and application of the immobilized carrier. The biological sample fixing carrier comprises a substrate and a composite layer of bovine serum albumin coupled biotin and neutral avidin, wherein the composite layer is fixed on the surface of the substrate; the bovine serum albumin coupled biotin and neutral avidin composite layer is connected to the surface of the substrate after being co-incubated with the substrate through bovine serum albumin coupled biotin, and then the neutral avidin is combined with biotin in the bovine serum albumin coupled biotin through co-incubation with the neutral avidin; the bovine serum albumin coupled biotin and neutral avidin composite layer is fixed on the surface of the substrate. The biomolecules on the surface of the carrier are high in fixing efficiency, good in uniformity, high in adaptability, high in signal-to-noise ratio and easy to operate.

The present disclosure relates to a method for increasing the sensitivity of latex immunoturbidimetry reagents. A biotin-streptavidin amplification system, a biotin-labeled antibody and streptavidin cross-linked latex microsphere are used, and the kit is characterized by comprising a first reagent and a second reagent, the first reagent comprises a buffer solution, a stabilizer, a polymerization accelerator, a preservative, a blocking agent and the biotin-labeled antibody, and the second reagent comprises a buffer solution, a stabilizer, a polymerization accelerator, a preservative, a blocking agent and a streptavidin cross-linked latex microsphere. The second reagent comprises a buffer solution, a stabilizer, latex microspheres labeled by streptavidin and a preservative. According to the present invention, the antibody is placed in the first reagent, such that the contact time of the antibody and the antigen is increased, the recognition efficiency is improved so as to improve the reaction sensitivity, and after the second reagent is added, the biotin-labeled antibody and the streptavidin latex microspheres are rapidly combined to form the agglutination so as to produce different reaction gradients, such that the sensitivity and the repeatability are significantly improved.

The invention provides an anti-streptavidin antibody which is high in specificity, high in sensitivity, less in cross reaction and small in batch difference. The antibody not only can realize similar application of a streptavidin-biotin system, but also can be used in combination with the streptavidin-biotin system for related applications such as cell sorting, immunochromatography and the like.

The application provides a preparation method of a functionalized phage probe and application of the functionalized phage probe in detection of escherichia coli. The functionalized phage is a recombinant phage (M13KO7@SaBP) in which streptavidin binding peptide (SaBP) is fused and expressed at the N terminal of the main capsid protein P8 protein of M13K07 phage. In the application, the gene encoding SaBP (MDVEAWLGAR) is inserted into the N terminal of the P8 protein gene of M13K07 phage by site-directed mutagenesis to prepare M13K07@SaBP. The stable signal amplification is realized by using the abundant P8 protein (about 2700) of M13 phage and the super strong binding force of biotin-streptavidin, the interference of food sample matrix is reduced by combining the magnetic separation technology, and a detection method of escherichia coli with high sensitivity and small sample matrix interference is constructed.

The invention relates to a multi-target gene detection method based on a liquid phase chip, which comprises the following steps: S1, target genes: selecting O-type serum antigens to synthesize key genes; s2, probe design: synthesizing key genes aiming at seven serotype antigens, and designing a specific primer pair; s3, Luminex microsphere coding and coupling: using MagPlex microspheres with different fluorescence codes, and fixing a probe on the surface of the microspheres through a carboxyl-amino coupling method; s4, carrying out multiplex PCR amplification and hybridization detection; s5, a data analysis algorithm is adopted, and a threshold value is set, wherein a negative control MFI mean value + 3 * standard deviation is a Cuff value; and positive judgment: the MFI value of the microsphere corresponding to a certain serotype is greater than or equal to Cuff, and the signal-to-noise ratio (S / N) is greater than or equal to 5. By adopting the technical scheme, the method is based on a Luminex liquid phase chip technology, target gene sequences are amplified through multiple PCR (Polymerase Chain Reaction), and high-flux specific detection on seven serotypes of Escherichia coli is realized by combining microsphere coding probe hybridization and a biotin-streptavidin signal amplification system.

The invention provides a streptococcus suis polysaccharide protein conjugate vaccine as well as a preparation method and application thereof, and belongs to the technical field of vaccine preparation. The vaccine comprises a polysaccharide-protein conjugate formed by coupling streptococcus suis type 2 capsular polysaccharide and streptococcus suis type 2 recombinant protein. The preparation method comprises the following steps: S1, preparing streptococcus suis type 2 capsular polysaccharide; s2, preparing streptococcus suis type 2 recombinant protein; s3, activating polysaccharide; s4, combining the biotinylated polysaccharide with the recombinant protein containing the avidin structural domain to form a stable polysaccharide-protein conjugate; s5, removing unbound proteins; and S6, mixing the polysaccharide-protein conjugate with the oil-water emulsion in proportion. By optimizing a coupling technology and a vaccine preparation formula, the immunogenicity and the protection effect of the vaccine are improved, the safety and the broad-spectrum cross protection capability of the vaccine are remarkably enhanced, the complexity and the cost of a vaccine production process are reduced, and the vaccine has a good industrial application prospect and a good popularization value.

The invention belongs to the technical field of biology, and particularly discloses a pH response type probiotic-liposome hybrid system, a preparation method and application thereof, and the pH response type probiotic-liposome hybrid system comprises engineered escherichia coli Nissle 1917, pinocembrin-loaded biotinylated liposome and an enteric polymer; wherein the engineered escherichia coli Nissle 1917 is in non-covalent binding with the biotinylated liposome loaded with the pinocembrin through surface display streptavidin, so that EcNPIN is formed, and the EcNPIN is coated with an enteric polymer, so that the pH response type probiotic-liposome hybrid system is formed. The pH response type probiotic-liposome hybrid system EcNPIN-L provided by the invention can resist the acidic environment of the stomach, completes pH response release and colonization in the intestinal tract, solves the problems of lack of intestinal tract localization of drugs and low probiotic treatment efficiency, improves the local intestinal tract concentration of pinocembrin, and promotes intestinal tract colonization of probiotics.

A method and kit are provided for detecting anti-drug antibodies (ADAs) against self-assembling trimeric biologics, such as XPro1595, a pegylated variant of soluble human Tumor Necrosis Factor, in biological samples, particularly human serum. The method employs an Affinity Capture Elution-Protein A / G (ACE-AG) assay that overcomes non-specific reagent interactions inherent in conventional bridging and standard ACE assays due to the biologic's dynamic monomer exchange. The assay utilizes a two-plate system: a streptavidin-coated plate with biotinylated trimeric biologic captures ADAs, which are eluted, neutralized, and transferred to a protein A / G-coated plate for specific immunoglobulin capture and detection with a sulfo-tagged trimeric biologic via electrochemiluminescence. The kit includes pre-coated plates, labeled biologics, elution and neutralization solutions, assay buffer, confirmatory reagent, and instructions. The assay offers a robust, specific, and sensitive solution for immunogenicity testing of trimeric biologics.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody 1E12 for specific detection of AAV6 and application of the monoclonal antibody 1E12. According to the monoclonal antibody 1E12 provided by the invention, a heavy chain variable region and a light chain variable region respectively comprise three complementary determining regions (CDR) corresponding to SEQ ID NO.1-3 and SEQ ID NO.4-6. The CDRs endow the antibody with high specificity and affinity to AAV6, the antibody can accurately recognize AAV6 virus without cross reaction with other serotypes, and the detection sensitivity reaches 4 * 10 < 6 > vg / ml level. The antibody is suitable for development of multiple detection tools such as a double-antibody sandwich ELISA kit, a test strip and an antibody chip, especially has excellent performance in a biotin-avidin amplification system, can be used for virus identification, titer determination and clinical dose evaluation of AAV6, and provides an effective means for standardized and high-throughput detection.

The invention relates to the technical field of biology, in particular to multi-layer streptavidin coated magnetic particles and a preparation method and application thereof. A self-assembly mode is adopted, NHS-PEG (n)-NHS is used as a connecting arm between streptavidin layers, when streptavidin molecular layers are increased, the biotin binding amount of the magnetic particles is remarkably increased, the space structure is enlarged through the PEG connecting arm between the streptavidin molecular layers, the steric hindrance between streptavidin molecules can be effectively reduced, and the biotin binding capacity of the magnetic particles is improved. Therefore, the difficulty of capturing target macromolecules is obviously reduced. Meanwhile, the magnetic particles coated by the process have obvious advantages in the aspect of dispersity. The streptavidin magnetic particles coated by the method can be applied to a magnetic particle chemiluminescence detection platform and used in an immunodetection kit.

A chimeric antigen receptor is disclosed that includes: (a) an extracellular high affinity streptavidin; (b) a hinge domain from CD8; (c) a CD28 transmembrane domain; (d) an intracellular 4-1BB and / or CD28 signaling domain; and (e) an intracellular CD3 zeta signaling domain, wherein (a)-(e) are in N-terminal to C-terminal order. Nucleic acids encoding this chimeric antigen receptor, and T and natural killer (NK) cells transformed with this chimeric antigen receptor are also disclosed. The use of this chimeric antigen receptor for the treatment of tumors is also disclosed.

The invention provides a multicolor visual semi-quantitative detection method for miRNA in skin interstitial fluid, which comprises the following steps: extracting a skin interstitial fluid sample in a minimally invasive manner by combining a microneedle patch with a vacuum negative pressure technology; the method comprises the following steps: incubating a skin interstitial fluid sample and a magnetic nanoprobe of which the surface is immobilized with a hairpin probe H1, opening H1 in the presence of target miRNA, triggering a subsequent hybridization chain reaction of a hairpin probe H2 and H3, and constructing a biotin-rich DNA compound on the surface of a magnetic bead; the method comprises the following steps: carrying out enzyme labeling by using an alkaline phosphatase-streptavidin conjugate, catalyzing ascorbic acid phosphate to generate ascorbic acid to reduce potassium iodate, and generating an iodine elementary substance to etch a gold nano bipyramid, so that the color of a solution is changed, and high-sensitivity detection on target miRNA is realized. The multi-color visual detection method provided by the invention is combined with the gold nano bipyramid localized surface plasmon resonance property change, so that near-full spectrum color change can be generated, and the portability of the sensor and the accuracy of visual analysis can be improved.

The invention relates to a multistage full-liquid-phase immunoassay method based on direct current magnetization response of superparamagnetic nanoparticles, and provides a brand-new three-stage superparamagnetic sensitive detection structure, interference caused by non-specific factors such as whole blood can be eliminated through reaction of a first-stage reagent and a second-stage reagent, and full-liquid-phase superparamagnetic sensitive signals are amplified and detected through reaction of the second-stage reagent and the third-stage reagent. According to the technical effects, the traditional advantages of a full-liquid-phase superparamagnetic sensitive detection technology are reserved, interference caused by most of whole blood is eliminated, signal amplification is carried out through a biotin avidin system, the detection sensitivity is improved, the clinical application level can be achieved, and the method is suitable for popularization and application. As a brand-new immunodetection protein technology which is completely put forward in China, the method has extremely important industrial and social values.

This invention provides a double-antibody sandwich SA-ELISA detection kit for Fasciola hepatica infection in sheep. A double-antibody sandwich SA-ELISA method for detecting Fasciola hepatica CAg (cag) is established using mouse anti-Fasciola hepatica D38 monoclonal antibody and rabbit anti-Fasciola hepatica D38 polyclonal antibody. This detection uses monoclonal antibodies as coating antibodies, resulting in high specificity. Furthermore, the introduction of a biotin-streptavidin signal amplification system enhances sensitivity. It offers advantages such as high accuracy, good stability, simple operation, rapid detection, and easy interpretation, making it suitable for rapid clinical diagnosis and epidemiological surveys at the grassroots level.

This invention discloses a homogeneous microsphere based on singlet oxygen self-circulating aggregation-induced emission, its preparation, and a wash-free detection method, which improves the sensitivity and efficiency of wash-free luminescent oxygen channel immunoassay. This invention successfully prepared AIE receptor microspheres by embedding the photosensitizer AIER dye, ultra-bright AIEG dye, and singlet oxygen-responsive dye SO into carboxyl-modified polystyrene nanoparticles. Simultaneously, an antibody-1-labeled AIE receptor microsphere solution, an antigen-containing test solution, and biotinylated antibody-2 were added to a 96-well plate, followed by streptavidin-modified donor microspheres. After wash-free incubation, the fluorescence signal value was measured, and the concentration of antigen in the test solution was obtained according to a standard curve. This platform completes wash-free, highly sensitive detection within 5 minutes, innovatively combining the aggregation-induced emission characteristics of AIEgens and a singlet oxygen cycling strategy, providing an efficient and universal solution for wash-free diagnostics.

The invention relates to a porcine bacterial polysaccharide-viral protein conjugate vaccine as well as a preparation method and application thereof, and belongs to the technical field of animal vaccines. The vaccine takes porcine bacterial polysaccharide and virus protein as raw materials, and a polysaccharide-virus protein conjugate is formed through coupling of a biotin-avidin system; wherein the virus protein is selected from one of classical swine fever virus E2 protein, porcine circovirus type 2 Cap protein, porcine pseudorabies virus gD protein and the like, and the porcine bacterial polysaccharide is selected from one of streptococcus suis capsular polysaccharide, porcine pasteurella multocida capsular polysaccharide and the like. The vaccine can simultaneously induce an organism to generate a high-level IgG antibody aiming at porcine bacterium capsular polysaccharide and virus protein, so that synergistic immune protection on porcine bacterium and virus infection is realized, and a broad-spectrum cross immune effect is achieved.

The preparation method comprises the following steps: modifying and connecting IL-15 and PD-1 protein molecules by using biotin, modifying PLGA-PEG by using avidin, and finally preparing the double-targeting nano-micelle through specific binding of the biotin and the avidin and a self-assembly effect of the PLGA-PEG. The dual-targeting nano-micelle IL-15 / PD-1 / PEG-PLGA, which can efficiently target and activate NK cells and target surface high-expression PD-L1 tumor cells, is synthesized and prepared. The mole number of IL-15 and PD-1 loaded on the surface of the dual-targeting nano-micelle is close to 1: 1, and the dual-targeting nano-micelle is regular in form, uniform in dispersion and in the shape of a sphere with the particle size of 254.76 + / -28.02 nm. Meanwhile, it is verified that the dual-targeting nano-micelle IL-15 / PD-1 / PEG-PLGA can effectively improve the recognition and killing efficiency of the NK cells on tumor cells in vivo and in vitro.

Disclosed herein are chromatographic materials comprising crosslinked streptavidin molecules. The crosslinked streptavidin chromatographic materials may be used to prepare affinity chromatographic materials using biotinylated affinity agents, such as a biotinylated antibody, biotinylated antigen-binding fragment, or biotinylated oligonucleotide. Due to the crosslinked nature of the streptavidin molecules, the materials provided herein have reduced to no streptavidin leachate, resulting in improved performance.