Abstract: A cyclical and continuous device and method for wet sieving of polysaccharide granules are provided. The device includes a first dosing tank, a second dosing tank connected to the first dosing tank by a first circulation pump, a first suction filtration tank connected to the second dosing tank by a second circulation pump, and a second suction filtration tank connected to the first dosing tank by a third circulation pump. An overflow port provided on a side wall of the second dosing tank is higher than a feed port of the first dosing tank. A sieve of a mesh filter for coarse powder is disposed in the first dosing tank. A sieve of a mesh filter for fine powder is disposed in the second dosing tank. A stirring device is disposed in both the first dosing tank and the second dosing tank.

Abstract: The present invention provides a method for removing an organic solvent from starch hemostatic microspheres, comprising the following steps: 1. taking to-be-dried starch hemostatic microspheres and laying them flatly on drying trays with attention to laying them as uniformly and thinly as possible; 2. taking an adsorbent and subpackaging it into dialyzing paper bags for sealing; and 3. placing the trays and the dialyzing paper bags completed in the previous two steps on separators of a low-temperature vacuum oven in layers, setting the oven temperature at 0-20° C., then vacuumizing and keeping pressure for 15-48 hours. The method provided by the present invention can reduce organic solvent residue in the starch hemostatic microspheres to less than 0.05%, which meets the requirements of relevant standards for medical devices, thereby improving safety of products.

Abstract: The application discloses a method for preparing chitin highly dispersible in aqueous phase and prepared chitin. After chitin is ground, dissolved, modified with glycidol and purified, a final product glycidol chitin is obtained. The glycidol chitin prepared according to this method has good solubility in purified water, and the concentration can reach 100 mg/mL, which is obviously different from common insoluble or poorly soluble chitin derivatives. Glycidol chitin may have a wide range of application prospects in biomedicine, cosmetics, absorbable materials, and other related aspects.

Abstract: The application relates to a sericin protein particle with an oxidative stress property, a method for preparing the same and use thereof. The particle is formed by sericin protein and a tellurium compound. In the method for preparing the sericin protein particle, bis(1-hydroxydodecyl) telluride is first prepared and then mixed with a solution of sericin protein, and a resulting solution is agitated continuously for some time to obtain telluride-modified sericin protein. Then, the solution of the sericin protein is added dropwise into absolute ethanol to obtain a precipitated product. An aqueous solution of the precipitated product and a solution of magnesium ions are mixed and agitated for a certain time to obtain the sericin protein particle with an oxidative stress property. The sericin protein particle disclosed is a hollow particle having a diameter in a range of 600-1250 nm, and is capable of loading biomacromolecule drugs or other components.

Abstract: A preparation method of a cross-linked sodium hyaluronate gel is disclosed, which including: preparing an alkaline aqueous solution of hyaluronic acid: formulating a sodium hyaluronate alkali liquor with the concentration of 10-30% g/ml; and carrying out a cross-linking reaction: the cross-linking agent used in the cross-linking reaction being divinyl sulfone or 1,4-butanediol diglycidyl ether, the cross-linking reaction being carried out in an alkaline aqueous solution of hyaluronic acid, the reaction temperature of the cross-linking reaction being 20-40° C., the time of the cross-linking reaction being 4-8 h, and the like. The method of this invention has many advantages, such as easily available raw materials, mild reaction conditions, high cross-linking efficiency, simple process and post-treatment, and easy operation.

Abstract: Related to is the field of polymer materials, and particularly related to are a method for preparing cross-linked hyaluronic acid gel and a cross-linked hyaluronic acid gel prepared by the method. Under an alkaline condition, a disulfide cross-linking agent is dropwise added into an alkaline solution of hyaluronic acid for cross-linking reaction, and after the reaction is completed, dialysis and freeze drying are carried out to obtain the cross-linked hyaluronic acid gel. A new disulfide cross-linking agent N,N-bis(acroloyl)cystamine is introduced, and it effectively solves degradation regulating problems of cross-linked hyaluronic acid; the disulfide bond ratio is controllable, which can effectively improve a cross-linking modification degree ratio in the cross-linked hyaluronic acid, thereby solving the problem of difficult degradation of highly cross-linked hyaluronic acid gel in the past. The cross-linked material has potential applications in aspects of drug carriers and tissue engineering scaffolds.

Abstract: A developable hyaluronic acid microspherical embolic agent includes a hyaluronic acid and an X-ray opaque contrast material; wherein the hyaluronic acid is a modified hyaluronic acid, wherein a modifying method for preparing the modified hyaluronic acid is cross-linking, grafting, esterification, or recombination, and is preferably cross-linking.

Abstract: Disclosed is a method for preparing cross-linked hyaluronic acid-based cell scaffold material. The hyaluronic acid-based cell scaffold is obtained by subjecting a hyaluronic acid and a disulfide cross-linking agent to an amidation reaction, followed by dialysis-freeze drying. The cell scaffold has abundant pores, good mechanical strength which ensures that the scaffold does not rupture in transplantation, and good biocompatibility. The method is advantageous in that the raw material is easy to obtain, the reaction condition is moderate, and the process is simple. Cross-linked networks of the prepared hydrogel contain disulfide bonds, which can quickly split into single chains at the presence of small molecular glutathione. The hyaluronic acid-based cell scaffold has flexibly controllable mechanical property, disaggregation ability, and swelling property, and therefore has wide applications in facilitating cartilage injury repair, skin repair, cell culture, etc.

Abstract: A method of preparing an oxidized starch haemostatic material, including adding a starch raw material to an external circulation pulsatile reactor; switching on a pump to allow inflow of dry air for drying the raw material; switching on a heat exchanger; vacuumizing the reactor; opening a nitrogen dioxide pipeline and a dry air pipeline; pumping in a mixed gas; controlling temperature at 0-120° C. by the heat exchanger; wherein nitrogen dioxide is contacted with the raw material to trigger a selective oxidation reaction and is continuously recycled; an airflow circulation switch is switched on and off at a pulsating ratio of 1:1-10 to carry out airflow pulsation; stopping inflow of nitrogen dioxide and continuing airflow circulation for 5-30 minutes; after completion of the reaction, adjusting to room temperature; vacuumizing the reactor and treating exhaust gas; allowing nitrogen gas to flow in for rinsing the replaced reactor until completion.

Abstract: Disclosed is a method for preparing an oxidized cellulose hemostatic product, including using a sodium hydroxide solution with the concentration of 1 to 5% to pre-process a cellulose product; after removing lignins or impurities on the fiber surface, using an alkaline solution to activate the fiber surface further; after the activating treatment, using demin-water for washing until it is neutral and drying the obtained cellulose product in air to obtain a raw material; using a sodium hydroxide solution with the concentration of 5 to 20% as a solvent; adding the cellulose product, carbamide and ZnO that are 3 to 10%, 2% and 2% of the sodium hydroxide solution respectively.