16 results about "Free thiol" patented technology

The present disclosure relates to methods and kits for detecting a free thiol in a substrate as well as methods for quantifying the amount of free thiol in a substrate. In particular, the present disclosure provides a fluorescent Ellman assay for enhanced sensitivity of free thiol detection and quantification.

The present invention relates to a method for preparing a modified protein composition under conditions in which the free thiol groups of β-lactoglobulin are exposed to and modified by a reaction with an oxidized phenol compound. The resulting modified protein product (e.g., a protein-rich beverage product) has been found to have excellent performance, and in particular, it has been shown to reduce the level of unpleasant odors during sterilization heat treatment at a neutral pH and when such beverage products are consumed.

This invention relates to the field of microcapsule preparation technology, and more particularly to a method for preparing probiotic microcapsules. The invention involves mixing a probiotic suspension with a tris(2-carboxyethyl)phosphine solution and performing a reduction reaction to obtain a thiolized probiotic suspension. Then, a thiolized polysaccharide is mixed with the thiolized probiotic suspension and subjected to a covalent bonding reaction to obtain probiotic microcapsules. This invention uses a simple chemical reaction to reduce the disulfide bonds on the surface of probiotics to free thiols, enabling the thiolized polysaccharide and probiotics to covalently bind, resulting in a stronger bond between the polysaccharide and the probiotics. The microcapsules prepared from the modified polysaccharide and probiotics can also bind to the mucin-rich mucus layer in the intestinal lining, undergoing a catalyst-free thiol-disulfide exchange reaction, colonizing the mucus layer in the intestine, and producing better therapeutic effects for intestinal diseases and enhanced probiotic benefits.

The application belongs to the field of antitumor drug preparation, and particularly relates to albumin binding and non-binding gemcitabine prodrugs, and a preparation method and application thereof. The acryloyl chloride gemcitabine prodrug is a compound formed by bridging gemcitabine and acryloyl chloride through an amide bond, and the two non-albumin binding prodrugs are compounds formed by bridging gemcitabine and 3-succinimidyl propionic acid / propionic acid through an amide bond. The ethylene group in the prodrug is a binding target for the free thiol group of the 34th cysteine on albumin, can be rapidly and specifically combined with albumin in the systemic circulation, and further forms an albumin prodrug complex. The complex can significantly improve the stability of gemcitabine in the systemic circulation, and prolong the systemic circulation time. The macromolecular prodrug strategy designed in the application can improve the delivery efficiency of chemotherapeutic drugs, improve the antitumor effect of chemotherapeutic drugs, and provides a new direction and new ideas for the delivery of chemotherapeutic drugs.

The application discloses a kind of complex and its preparation method and application, including cysteine modified chitosan and peroxidase, and cysteine modified chitosan and peroxidase form stable complex;The complex provided by the application has good stability, and particle size is uniform;The complex described in the application has simple composition, and preparation and purification method are simple, production efficiency is high, it is helpful to batch production and popularization and application, cost can be controlled, and even with high concentration of the complex described in the application and eye drop is applied to mouse or rabbit eye surface, still cannot cause eyeball anomaly by safety experiment verification;The free thiol group on the surface of cysteine modified chitosan can increase the adhesion of complex on the ocular surface, so as to overcome the limitation of rapid clearance of ocular drug, significantly prolong the residence time of peroxidase on the ocular surface, greatly improve the feasibility of peroxidase in the field of dry eye treatment application.

This invention belongs to the field of genetic engineering technology, specifically relating to a method for improving the stability of antibody-drug conjugates (ADCs) and cysteine-engineered antibodies. The invention provides a method for improving the stability of ADCs by mutating at position 14 of the first frame region of the antibody's light chain variable region to cysteine; the antibody includes Fab antibodies and / or single-chain antibodies. This invention performs a site-directed mutation at amino acid position 14 of the first frame region of the antibody's light chain variable region. This site is far from the antigen-binding interface, thus preserving antigen-binding activity while providing a modifiable free thiol group, and simultaneously reducing interchain mismatches caused by the traditional C-terminal tandem cysteine ​​residue.

This invention provides a method for preparing recombinant serum albumin with thiol preservation and conformational fidelity, relating to the field of recombinant protein preparation. Its key feature is the use of a dual protection system—low temperature and temperature control throughout the process, and specificity—to directionally protect the free thiol group at the Cys34 position and maintain the protein's native conformation. Combined with a two-stage purification process of first-stage ultrafiltration and second-stage chromatography, impurities and aggregates are efficiently removed. The final product is obtained through conformational locking and aseptic filtration. The advantages of this invention are: the recombinant serum albumin exhibits a Cys34 free thiol group retention rate ≥90%, purity ≥98%, and aggregate content ≤1%, demonstrating high activity, high stability, and high formulation compatibility. The process is animal-free, industrially scalable, and has high patent barriers, making it particularly suitable for high-end cosmetic raw materials.

The application discloses a kind of small ice wheat dough and gluten protein by enzyme modification, comprising the following steps: different adding amount Xyn, β-Glu small ice wheat dough preparation;Xyn, β-Glu and Xyn+β-Glu different adding amount on the texture determination of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu different adding amount on the determination and analysis of free thiol and disulfide bond of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the determination and analysis of thermal characteristics of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the determination and analysis of dynamic rheology and creep-recovery of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the influence analysis of small ice wheat gluten;Three kinds of different adding amount of enzyme all have significant difference (P<0.05) on the texture parameter of dough, the influence law of different adding amount of Xyn, β-Glu and Xyn+β-Glu on dough is basically identical, and hardness and chewiness present the trend of first falling and then rising with the increase of adding amount, wherein the hardness of 4mg / kg Xyn+40mg / kg β-Glu decreases most obviously, is 776.873±31.969g, and is reduced by 24.89% compared with small ice wheat dough without adding enzyme.

The invention belongs to the technical field of antibody-oligonucleotide conjugate preparation, and particularly relates to an antibody-oligonucleotide conjugate drug and a preparation method thereof. The structural formula of the antibody-oligonucleotide coupling medicine is as follows: Ab-(L-D) n, ab represents an antibody and is selected from a mutated IgG antibody or a Fab antibody; d represents an oligonucleotide drug; l represents a connecting unit for connecting the Ab part and the D part, and is selected from maleimide-activated polyethylene glycol; and n represents the number of connecting units and is selected from 1 or 2. According to the present invention, the amino acid residue at the specific site is subjected to cysteine substitution mutation to obtain the antibody having the free sulfydryl group and the functional activity of which is not affected, such that the specific reaction site is provided for the oligonucleotide drug having the maleimide group, the drug binding position can be effectively controlled, and the drug binding efficiency is improved. The directed, controllable and efficient coupling of the antibody and the oligonucleotide drug is realized, and the homogeneity of different batches of drugs and the batch production stability are favorably improved in production.

This invention discloses an oligomeric wheat peptide and its preparation method, belonging to the field of plant peptide technology. The method uses wheat bran as raw material, which undergoes extrusion puffing and ultrafine grinding pretreatment, followed by alkaline extraction combined with amylase hydrolysis to obtain a wheat bran protein extract. Subsequently, it undergoes low-temperature controlled denaturation pretreatment, followed by freeze-thaw cycles to partially unfold the protein. Cysteine ​​is added as a conformation-locking agent to form reversible mixed disulfide bonds with exposed free thiol groups to stabilize the metastable conformation. Then, site-specific enzymatic hydrolysis is performed in an ultrasound-assisted enzyme membrane reactor, with ultrafiltration separating the oligopeptides in real time. Finally, electrodialysis desalination, nanofiltration concentration, and spray drying yield high-purity wheat bran oligomeric wheat peptides with gastric mucosal protective activity. This invention achieves high-value utilization of wheat bran components, with a green and efficient process, and produces peptides with high uniformity and strong activity, significantly improving the quality and market competitiveness of wheat peptide products.

The invention discloses a preparation method of a PD-L1 remodeling probe, and belongs to the technical field of probe preparation. Dissolving galactose oxidase containing free sulfydryl in a phosphate buffer solution; the preparation method comprises the following steps: adding NHS-polyethylene glycol 1000-maleimide into galactose oxidase, and mildly stirring at room temperature to obtain a mixed solution; transferring the mixed solution into a dialysis membrane, and dialyzing with a phosphate buffer solution for 12-16 hours; after dialysis is completed, adding a peptide fragment, reacting at room temperature to promote the reaction of NHS ester and amino of the peptide fragment, and finally generating a peptide-polyethylene glycol 1000-galactose oxidase covalent complex; the covalent complex is analyzed through lauryl sodium sulfate-polyacrylamide gel electrophoresis, if the molecular weight of a band is increased and migration occurs, the complex is successfully coupled, and the PD-L1 remodeling probe is obtained. The PD-L1 remodeling probe prepared by the invention can be used for specifically and efficiently oxidizing galactose / N-acetylgalactosamine residues at the tail end of PD-L1 to generate aldehyde groups so as to be subjected to biological orthogonal reaction with hydrazide groups.

Described herein is a process using a novel composition for strengthening hair by crosslinking the free thiols naturally present on hair or resulting from the reduction of disulfide bonds in damaged or treated hair. The process involves applying a composition containing an active agent that interacts with free thiols present in hair, forming a covalent carbon-sulphur bond, thereby enhancing the structural integrity of hair. The present invention provides a rinse off or leave-in treatment that effectively reduces breakage and restores strength to weakened or damaged hair and helps in increased longevity of reshaped hair such as straightening or curling.

The invention discloses a method for regulating and controlling an aggregation path and gel characteristics of soybean protein isolate based on polymerization degree specific chitosan oligosaccharide, which comprises the following steps: preheating an SPI (Serial Peripheral Interface) solution, and uniformly mixing the SPI solution with a COS (DPlt; the degree of aggregation is lt; on one hand, the COS of 1, 6 guides the LAs to perform ordered assembly, optimizes protein space orientation, and promotes efficient formation of disulfide bonds; on the other hand, the small aggregate SAs is maintained in a non-covalent interaction stable state which is compact in structure and rich in free sulfydryl. An ordered precursor composed of a covalent cross-linked LAs skeleton and a non-covalent stable SAs filling unit constructs a compact and continuous three-dimensional network structure with high storage modulus in the subsequent thermally induced gelation process, and the mechanical strength and the structural stability of the SPI gel are remarkably improved.

The present disclosure relates to methods and kits for detecting free thiols in a substrate and methods for quantifying the amount of free thiols in a substrate. In particular, the present disclosure provides a fluorescent Ellman assay for improving the sensitivity of free thiols detection and quantification.

This invention belongs to the technical field of peptide coordination polymer hydrogel materials, and discloses a peptide coordination polymer hydrogel for detecting ATP levels in cancer cells, as well as its preparation method and detection device. The composition provided by this invention includes Ag. + And RGD cyclic peptides, which include free thiol and free guanidinyl groups, Ag + Ag is formed by coordination with RGD cyclic peptide. + -RGD cyclic peptide coordination polymer, Ag + -RGD cyclic peptide coordination polymers can undergo hierarchical assembly to achieve gelation in the presence of ATP or within a gelling concentration range, and the resulting gels exhibit excellent optical and mechanical responsiveness to ATP. Ag exists in solution or gel form. + -RGD cyclic peptide coordination polymers can serve as functional materials for the specific capture and immobilization of cancer cells and ATP detection, showing great promise for real-time-in-situ monitoring of cancer cell activity, evaluation of the therapeutic effects of anticancer drugs, or development of novel tumor diagnostic devices.

The present invention pertains to a method of preparing modified protein compositions under acidic conditions that expose and modify free thiol groups of beta-lactoglobulin through reaction with oxidized phenolic compounds. The resulting modified protein product has been found to have an excellent performance in e.g. protein-rich beverage products and has particularly been found to give rise to a reduced level of unpleasant odours during sterilizing heat-treatments at neutral pH and during consumption of such beverage products.