The hyaluronate acid is a kind of straight chain with high molecular weight, which widely distributes in extracellular matrix of connective tissue of animals and human. Its characteristics of irregular curly status in solution and fluid dynamics endow it with important physical properties, i.e. high viscoelasticity, plasticity, permeability and good biocompatibility. Therefore, it is a kind of widely-used biological absorbable material and plays a unique role in medicine field. The hyaluronate acid molecule could extend greatly and curl randomly in solution, which makes it occupy a large space. Its fluid dynamics volume is 103 times larger than that before hydration. The molecular chains twine with each other to form continuous reticular formation, on which the water molecule acts through polar bond and hydrogen bond, making the sodium hyaluronate be similar to molecular sponge that could absorb and maintain moisture that is thousand times more than its own weight. So it is the best humectant recognized worldwide, and thus widely used in emulsifier, thickener and essence fixative. It is proved that the hyaluronate acidis the best carrier of ophthalmic preparation at present, which does not only increase biological availability of medicines, but also reduces stimulation of drugs to eyes, promotes healing of eye wound, and relieves discomfort of eyes quickly. The sodium hyaluronate is used not only as the above-mentioned carrier of ophthalmic preparation in ophthalmology, but also plays an important role in ophthalmic surgery. The sodium hyaluronate is a kind of transparent, sterile, nontoxic, non-infected, and nonantigenic viscoelastic substance, of which the viscosity is 5000 times higher than that of aqueous humor. 1% SH injection is usually injected into the anterior chamber to maintain a certain spatial depth in anterior chamber, and the stick-slip property of the SH is helpful to take out foreign bodies and conduct intraocular implantation. The clinical application shows that it is also very useful in operations of diseases like hyphema, corneal laceration, iris laceration, old traumatic cataract, and foreign bodies retention in anterior chamber as well as operations like intraocular implantation, cataract extraction and emulsification, cyclodialysis, and anti-glaucoma operation. OA is a more common chronic osteoarthropathy, which is mainly caused by cartilage degenerative disease and cartilage surface injury. The sodium hyaluronate is the important component of joint synovial fluid and cartilage matrix. The sodium hyaluronate, which is secreted by B cells of lining cells inside synovium, exists in articular cavity in various forms. It has functions of participating in extracellular electrolyte and moisture regulation, lubricating joints, anti-infection, and healing wounds. As exogenous viscoelastic substances, the sodium hyaluronate is injected into knee joint cavity, which has good and sustained clinical effects on patients suffering from light and moderate OA. The exogenous sodium hyaluronate, together with other amino-dextran and collagen, plays an absolutely necessary template role in repair of injured tissue. It is proved that the equivalent combination of sodium hyaluronate and fibrocyte is one of reasons of scar-free repair of injured part. Since the sodium hyaluronate was first used in repair process of flexor tendon to reduce adhesion in 1980, it has been widely used in adhesion prevention after operations of abdominal cavity, pelvic cavity, tendon, and dura mater etc. Quantities of animal experiments and clinical applications show that the sodium hyaluronate is safe and effective in application of preventing and reducing surgical adhesion. It could be effective for parts liable to be adhered, which is easy to use, causes no impact on normal healing process of wound, and has good biocompatibility and degradability. Technical Indexes of Sodium Hyaluronate (Medical Grade) Items Technical IndexesCharacterWhite or almost white powder with high hygroscopicity, soluble in water, insoluble in acetone, ethanol, and ether Identification(1) The fuchsia solution would be produced after identification in accordance with methods of Appendix A of YY-0308-2004 Medical Sodium Hyaluronate Gel. (2) Take the product of 0.01g, and then dissolve it by adding 10ml purified water, and the white flocculent precipitate would be produced after adding 2-3 drops of cetyl pyridinium chloride (1→20). (3) Take the product of 0.01g, and then dissolve it by adding 10ml purified water, burn the platinum wire, and the flame is yellow. Appearance of SolutionA600nm≤0.01PH Value5.0-8.5Nucleic AcidA260nm≤0.5Protein≤0.1%Chlorine≤0.5%Fe≤80ppmLoss on Drying≤20.0%SterilityIt is should be sterileToxin in Bacteria≤0.05IU/mgContent95.0-105.0%