5results about How to "Good tissue permeability" patented technology

The application belongs to the technical field of biological medicine, and particularly relates to a polypeptide degradation agent for targeted degradation of CD26 and a preparation method and application thereof. The polypeptide degradation agent is obtained after coupling of a tetrapeptide and lenalidomide. The amino acid sequence of the tetrapeptide is any one of SEQ ID NO. 1 and SEQ ID NO. 2. The polypeptide degradation agent can specifically target and degrade DPP4, i.e. CD26, but cannot degrade DPP4 isozymes such as DPP7, DPP8 and DPP9, and thus has high selectivity. In addition, the polypeptide degradation agent has small molecular weight, one end is a natural short peptide, has good tissue compatibility, can quickly degrade target proteins in 6 hours, and thus has good tissue permeability.

The application provides a method for constructing a double-signal sensing platform based on a non-copper nanometer enzyme AuPt@PBA@L-Pd and application, and a multifunctional nanometer composite material AuPt@L-Pd@PBA (hereinafter referred to as APL) with the effects of an oxidase-like enzyme, a peroxidase-like enzyme and a laccase-like enzyme is prepared. The composite nanometer enzyme has a regular cubic morphology, takes PBA as a base material, loads L-Pd through an amide bond, simultaneously collects the advantages of the MOF material PBA and L-Pd, has multiple enzyme-like effects, and can catalyze different chromogenic substrates. The AuNPs and PtNPs on the surface of APL not only provide good binding sites for antibodies, but also successfully prepare a biological composite probe Ab2@APL, further amplify the sensing signal, and improve the sensitivity of the sensing platform. It is worth mentioning that APL has the effect of a laccase-like enzyme, but does not contain copper ions, and further improves the biocompatibility. Based on the high catalytic activity and multifunctional nanometer enzyme Ab2@APL, a multi-signal sensing platform can be constructed, and the application prospect in more fields is wider.

The invention belongs to the technical field of biology, and relates to a preparation method and application of a shark nano antibody targeting pancreatic lipase. The amino acid sequence of the shark nano antibody VNAR-A4 is as shown in SEQ ID No. 10. The molecular weight of the shark nano antibody VNAR-A4 prepared by the invention is about 15 kDa, is smaller than that of a traditional monoclonal antibody, has a slender CDR3 structure, and can be better combined with hidden epitopes of antigens; the shark nano antibody VNAR-A4 is good in stability, can keep activity under an extreme pH condition, and has good affinity and specificity with PL; the shark nano antibody VNAR-A4 is expressed by using an escherichia coli prokaryotic expression system, is easier for genetic engineering modification, and can be prepared in a large scale. The shark nano antibody VNAR-A4 has the potential of inhibiting the activity of pancreatic lipase, and a novel fat hydrolysis inhibiting reagent is provided for treating obesity.

The invention discloses a shark source single-domain antibody combined with polyphenol oxidase and application of the shark source single-domain antibody. The nucleotide sequence of the single-domain antibody is labeled as SEQ ID NO.1, the amino acid sequence corresponding to the single-domain antibody is recorded as SEQ ID NO.2, the shark-source single-domain antibody is used for detecting the concentration of polyphenol oxidase, and the preparation method of the single-domain antibody comprises the following steps: carrying out biological elutriation on a shark-source single-domain antibody library by taking polyphenol oxidase as target protein; and finally, screening to obtain a single-domain antibody sequence with high specificity to polyphenol oxidase, constructing the single-domain antibody sequence into an eukaryotic expression vector, and expressing and purifying shark source single-domain antibody Fc fusion protein by using HEK 293F cells. The prepared single-domain antibody shows good stability, high specificity and high affinity, a theoretical basis is provided for prawn blackening inhibition with polyphenol oxidase as a target spot and aquatic product quality safety monitoring, and the single-domain antibody can stably detect the concentration of polyphenol oxidase.

This invention provides an aptamer targeting the growth hormone receptor and its uses, the nucleotide sequence of which is shown in SEQ ID NO.1 or SEQ ID NO.2. This invention utilizes a modified SELEX technique to perform multiple rounds of screening targeting recombinant GHR protein, obtaining specific nucleic acid aptamers with high affinity for GHR (KD values ​​at the micromolar level). In vivo distribution experiments show that the fluorescently labeled aptamer can efficiently and specifically accumulate in white adipose tissue (including inguinal and gonadal fat) at the in vivo level, exhibiting excellent tissue targeting. The nucleic acid aptamer and its derivatives of this invention can be used to prepare drugs or diagnostic reagents targeting adipose tissue, for example, for the prevention or treatment of metabolic diseases such as obesity, type 2 diabetes, fatty liver, hyperlipidemia, or cardiovascular disease.