Abstract: The present invention provides a high-stability daptomycin composition for injection and preparation method therefor and use thereof. The daptomycin composition for injection comprises daptomycin and a pharmaceutically acceptable carrier, and the pharmaceutically acceptable carrier contains a divalent metal salt, a pH regulator, and an osmotic pressure regulator; and the molar ratio of daptomycin to divalent metal salt in the daptomycin composition for injection is 1:1.0 to 1:3.5. The daptomycin composition for injection of the present invention significantly improves the stability of the preparation, facilitates the storage and transportation of the preparation at room temperature, and ensures the safety of drug use; And the preparation method of the present invention has advantages such as green environmental protection, suitability for industrialization.

Abstract: A method of preparing an enhanced yellow-emitting carbon dots includes dissolving citric acid and urea in N,N-dimethylformamide, reacting at a temperature of 150-180° C. for 4-8 h to obtain a carbonized mixture, separating and purifying the carbonized mixture through column chromatography using an eluent prepared according to a volume ratio of dichloromethane to methanol from high to low, collecting a solution obtained by elution when the volume ratio of dichloromethane to methanol is 1:1-2, performing rotary evaporation to remove the solvent, and drying to obtain the yellow-emitting carbon dot. The yellow-emitting carbon dot with fluorescence intensity enhanced with the increase of temperature is synthesized. The yellow-emitting carbon dots has application value in the fields of temperature detection, biological imaging, photoelectric equipment and the like.

Abstract: A method of preparing an enhanced yellow-emitting carbon dots includes dissolving citric acid and urea in N,N-dimethylformamide, reacting at a temperature of 150-180° C. for 4-8 h to obtain a carbonized mixture, separating and purifying the carbonized mixture through column chromatography using an eluent prepared according to a volume ratio of dichloromethane to methanol from high to low, collecting a solution obtained by elution when the volume ratio of dichloromethane to methanol is 1:1-2, performing rotary evaporation to remove the solvent, and drying to obtain the yellow-emitting carbon dot. The yellow-emitting carbon dot with fluorescence intensity enhanced with the increase of temperature is synthesized. The yellow-emitting carbon dots has application value in the fields of temperature detection, biological imaging, photoelectric equipment and the like.

Abstract: The present disclosure is directed to expression vectors, comprising a weakened SV40 promoter, and recombinant mammalian cells capable of producing high levels of a polypeptide of interest, methods of generating and using such recombinant mammalian cells.

Abstract: The present disclosure is directed to expression vectors, comprising a weakened SV40 promoter, and recombinant mammalian cells capable of producing high levels of a polypeptide of interest, methods of generating and using such recombinant mammalian cells.

Abstract: The present disclosure is directed to expression vectors, comprising a weakened SV40 promoter, and recombinant mammalian cells capable of producing high levels of a polypeptide of interest, methods of generating and using such recombinant mammalian cells.

Abstract: The invention discloses a D-biotin preparation method. In the prior art, with a synthesis method utilizing malonic acid diester as raw materials, impurities are also produced along with the obtained D-biotin. The D-biotin preparation method is characterized in that with the presence of dimethyl sulfoxide and inorganic base as catalysts, methane tricarboxylic acid trialkyl ester and (3aR, 8aS, 8bS)-1,3-dibenzyl-2-oxo-10H-iminazole [3,4-d] thiophene [1,2-a] sulfuryl halide are subjected to condensation reaction in methylbenzene solvent to obtain intermediate (3 aS,4S,6aR)-1,3-dibenzyl-4-(?,?,?-3-methoxycarbonylbutyl)-4H-1H-thiophene[3,4-d]iminazol e-2,4(1H)-ketone, and the D-biotin is obtained after the intermediate is treated by the aftertreatment method. By the D-biotin preparation method, production of the impurities is avoided, quality of the biotin is greatly improved on the existing basis, and side reaction is avoided too.

Abstract: Abstract The invention discloses a D-biotin preparation method. In the prior art, with a synthesis method utilizing malonic acid diester as raw materials, impurities are also produced along with the obtained D-biotin. The D-biotin preparation method is characterized in that with the presence of dimethyl sulfoxide and inorganic base as catalysts, methane tricarboxylic acid trialkyl ester and (3aR, 8aS, 8bS)-1,3-dibenzyl-2-oxo-10H-iminazole [3,4-d] thiophene [1,2-a] sulfuryl halide are subjected to condensation reaction in methylbenzene solvent to obtain intermediate (3 aS,4S,6aR)- 1,3 -dibenzyl-4-(?,?,?-3-methoxycarbonylbutyl)-4H- 1H-thiophene[3,4-d]iminazol e-2,4(1H)-ketone, and the D-biotin is obtained after the intermediate is treated by the aftertreatment method. By the D-biotin preparation method, production of the impurities is avoided, quality of the biotin is greatly improved on the existing basis, and side reaction is avoided too.

Abstract: The present disclosure is directed to expression vectors, comprising a weakened SV40 promoter, and recombinant mammalian cells capable of producing high levels of a polypeptide of interest, methods of generating and using such recombinant mammalian cells.

Abstract: The invention discloses the improved preparation method for D-Biotin. If the composite method takes the malonic acid diester as the raw material, the finial biotin will be generated with impurities. The features of the invention refers to the improved preparation method for D-Biotin includes: firstly, (3aS,4S,6aR)-1,3-dibenzyl-4-(?,?,?-3 -alkoxycarbonyl bytyl)-4H-1H-thiophene[3,4-d]iminazole-2,4(1H)-ketone is got after the methane tricarboxylic acid trialkyl ester and (3aR,8aS,8bS)-1,3-dibenzyl-2-oxo-10H-iminazole[3,4-d]thiophene[1,2-a]sulfuryl halide have the condensation reaction in the alkaline environment and then D-Biotin can be got after the reaction process of hydrolysis, decarboxylation and closed loop. The invention succeeds in greatly improving the biotin quality from the original basis and simultaneously avoids the generation of impurities and the occurrence of side reaction.

Abstract: An open-channel radiation sterilization system, comprising a channel, a radiation source and an electrical control means, characterized in that the fluid to be sterilized flows in under the radiation source and the sterilized fluid flows out above the radiation source in the channel; a first partition wall and a second partition wall are both provided in the channel, partitioning the channel into three parts, i.e.