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Zhishang Chemical

Pure Sericin CAS 60650-88-6

Molecular Formula: None

Formula Weight: 0

ZSpharmac: Pure Sericin Supplement

Product Name: Pure Sericin
CAS No: 60650-88-6
Purity: 99%

Basic Info

Product Name:Pure Sericin
Other Names:SERICIN
Place of Origin:Shandong, China
Brand Name:ZSpharmac
Type:Cosmetic Raw Materials
Appearance:Colorless Viscous Liquid
EINECS No.:1806241-263-5
Provide:Pure Sericin MSDS;
Pure Sericin COA

What is Pure Sericin?

Pure Sericin is a natural macromolecular protein wrapped on the surface of silk fibroin. It is mainly secreted by the silk glands of silkworms and is one of the main proteins that make up the silkworm cocoon. Because of its good water solubility, cell adhesion-promoting and proliferative activities, lower immunogenicity, and unique in situ fluorescence, antioxidant activity, and tyrosinase inhibitory properties, sericin is widely used in Fabric finishing coatings, cosmetic additives, as well as food, medicine, functional biological materials.

Pure Sericin is a water-soluble globular protein with a molecular weight of about 10-300kDa. The molecular weight of Pure Sericin in solution is affected by temperature and pH. Sericin is composed of 18 kinds of amino acid residues, among which the main amino acid residues are serine (Ser), aspartic acid (Asp), glycine (Gly), their contents are about 33%, 20% and 14% respectively ( as in Table 1). Amino acid residues contain a large number of strong polar groups such as hydroxyl, carboxyl, and amino groups, and polar side chain amino acids occupy more than 70% in sericin. The secondary structure of Pure Sericin is mainly random coil, and contains part of β-sheet structure and almost no α-helix structure, and the content of β-sheet structure close to silk fibroin is higher. The conformation is still controversial. Since Pure Sericin contains a large number of carboxyl groups and amino groups, it exhibits amphoteric properties by combining with hydrogen ions or hydroxide ions, and the isoelectric point of protein is the embodiment of amphoteric properties. The isoelectric point of sericin is 3.8~ 4.5.

When the hydrogen ions and hydroxide ions bound to the protein reach equilibrium and the net charge on the protein is zero, the pH of the solution at this time is the isoelectric point of the protein. When the pH value of the solution is low, Pure Sericin exists in the form of positive ions, and when the pH value in the solution is high, sericin exists in the form of negative ions. Pure Sericin is a globular protein whose polypeptide chain is tightly folded, the hydrophobic amino acid side chain is located inside the molecule, and the hydrophilic amino acid side chain is exposed to the water solvent outside, so the globular protein has good solubility in water solvent. . However, the molecular weight of sericin has a great influence on its solubility. Small molecule Pure Sericin can dissolve in cold water, and macromolecular sericin can dissolve in hot water. Pure Sericin is a natural biopolymer with a relatively large molecular weight. Therefore, the size of sericin particles is generally between 1 and 100 nm, which belongs to the range of colloidal particles. Therefore, Pure Sericin solution will also show dialysis, coagulation, and gelation. properties of colloidal solutions such as gelation and peptization.

Pure Sericin Properties:

1. Amphoteric properties and isoelectric point of Pure Sericin contains free shuttle groups and amino groups, which can interact to form bipolar ions and have amphoteric properties. In a solution with a lower pH value, sericin exists in the form of positive ions in a solution with a higher value, and sericin exists in the form of negative ions. The isoelectric point of Pure Sericin is: 3.8-4.5.

2. Colloidal properties of Pure Sericin sericin is a high molecular compound with a large molecular weight and a particle diameter of 1-100 nm. Because the particle size is in the range of colloidal particles, it shows the unique dialysis, coagulation, Gelling and peptizing properties.

3. The properties of Pure Sericin denatured sericin molecules often change when they are affected by some external physical or chemical factors, but these changes do not involve changes in the primary structure, and the covalent bond of the peptide chain is not broken, only A change in molecular conformation occurs, resulting in a change in properties. Its main manifestations are changes in physical properties, chemical properties and loss of biological activity, and the most prominent manifestation is the decrease in solubility, which will greatly reduce its use value. The main factors that cause Pure Sericin denaturation are temperature, pH value and organic solvent.

4. Swelling and dissolving of Pure Sericin Sericin is a kind of macromolecule. When it comes into contact with an appropriate liquid, it will automatically absorb the liquid and swell and become soft. After infinite swelling, it can dissolve in the liquid. In general, silk fibroin can only swell but not dissolve in water, but sericin can dissolve in hot water. This is the most important property of sericin, and it is also the basis for people to use water to make silk, scouring and degumming.

Pure Sericin Separation Method

1. Application in the field of cosmetics Generally speaking, the normal skin stratum corneum should retain 10% to 20% of moisture, so that the skin can be elastic, plump and shiny without cracking. The reason why a certain amount of water is retained in the stratum corneum is that, on the one hand, the sebum film has the ability to prevent water evaporation, and on the other hand, the stratum corneum contains natural moisturizing factors (NMF) with hygroscopic and moisturizing functions; sericin is rich in moisture. Contains polar amino acids, which contain polar groups such as -OH, -COOH, -NH2, and have similar ingredients and functions to moisturizing factors. Japan already contains sericin cosmetics, such as body lotion, facial cleanser, facial cleanser Wait. Studies have shown that the darkening of the skin is due to the oxidation of tyrosinase in melanocytes. Hideyuki Yamada’s research found that sericin can inhibit the activity of this enzyme and retain this ability after boiling. In sericin, tyrosine (Tyr), tryptophan (Trp) and phenylalanine (Phe) can absorb ultraviolet rays and prevent the skin from tanning and sunburn.

2. Application in the edible field More than 90% of the amino acids contained in sericin can be absorbed by the human body, and more than 17% of the amino acids contained in the amino acid are necessary for the human body. Among them, serine, glycine, and aspartic acid have special pharmacological effects: serine can effectively inhibit the increase of cholesterol in the blood, which can prevent and treat hypertension; inhibiting tuberculosis can be used to treat lung diseases. Glycine can reduce cholesterol at the same time, and has the effect of lowering blood sugar, preventing thrombosis, blood coagulation, and treating diabetes. Aspartic acid can reduce blood ammonia, protect the myocardium, treat angina pectoris, and also have a protective effect on the liver. Serine and glycine are also nutritional factors for glial cells, and sericin ingested (serine and glycine account for about half) can improve memory and prevent dementia. As an antioxidant, sericin can be used in the field of food, sericin can effectively inhibit fat peroxidation (food oxidation is mainly fat oxidation), and inhibit polyphenol oxidase, thereby inhibiting food browning. The study also found that Pure Sericin can promote the absorption of zinc, iron, calcium and other elements in mice.

3. In the field of fiber modification, the Pure Sericin is fixed on the surface of the fiber fabric through a cross-linking agent, so that the fiber has the original performance and the functional characteristics of Pure Sericin, which improves the wearability and value of the fabric. Polyester has high strength and good resilience, but it has poor moisture absorption and breathability, and poor wearing comfort, so it cannot be used as a better wearing fabric. Surface modification of polyester with Pure Sericin can improve the comfort of polyester.

4. Biomaterials Many studies have shown that Pure Sericin has the ability to act as a medical dressing. The water-absorbing properties of Pure Sericin help to maintain a relatively moist environment on the skin surface and can absorb exudate from wounds. Two-dimensional membranes and three-dimensional hydrogels and porous scaffolds prepared with sericin have been reported. In mouse experiments, not only as a dressing, but also as a Pure Sericin essence also showed very good wound healing properties and did not cause allergic reactions. Wounds treated with sericin exhibited less inflammatory responses compared to controls. In wounds treated with collagen and sericin, the epidermis of the Pure Sericin-treated group grew faster.

Pure Sericin Isolation Method

1. High temperature hot water method That is, by soaking silk in hot water, Pure Sericin is dissolved in hot water and silk fibroin is insoluble. Then, the silk fibroin is removed by filtration or centrifugation to obtain an aqueous solution of Pure Sericin. The sericin solution is then dried to obtain Pure Sericin powder. The sericin obtained by this method does not introduce other chemicals, but the yield is lower.

2. Sodium carbonate method The silk is immersed in an aqueous solution of sodium carbonate. At a certain temperature, Pure Sericin is dissolved in the aqueous solution of sodium carbonate, while silk fibroin does not dissolve. The silk fibroin is removed by filtration or centrifugation, and then the obtained sodium carbonate sericin aqueous solution is dialyzed, concentrated or dried to obtain sericin.

3. Acid precipitation method Utilizing the characteristics of Pure Sericin’s reduced solubility at the isoelectric point (pH 3.8-4.5), Pure Sericin is precipitated from the aqueous solution, and then recycled and used. This method is one of the most commonly used methods for separating proteins in industry.

4. Citric acid method Pure Sericin can be obtained by dialysis and concentration of the dissolved sericin citric acid solution by utilizing the property that Pure Sericin can be dissolved in boiling water of citric acid aqueous solution, while silk fibroin is insoluble. However, in this method, the protein is precipitated from the solution during dialysis, and the precipitated Pure Sericin is difficult to reconstitute.

5. Urea method A method in which Pure Sericin is obtained by dissolving sericin in aqueous urea solution, and then dialysis and concentration. The effect of this method on the molecular weight of sericin is much lighter than that of the high temperature hot water method and the sodium carbonate method. However, the Pure Sericin obtained by this method has obvious cytotoxicity.

6. Lithium bromide method This method uses lithium bromide aqueous solution to dissolve Pure Sericin at a lower temperature, and then dialyses and concentrates to obtain an ideal concentration of Pure Sericin aqueous solution. This method is a relatively mild method reported so far to separate sericin from silk.

About Us

The production base is located in Zhangqiu chemical industry park and Tai’an high-tech chemical industry park. laboratory and workshop in strict accordance with the GMP standard and the product fit national ISO9001 and ISO2000 standards.

“Zhishang” products are exported to Europe, North and South America, the Middle East, Asia Pacific and Africa area, so as to establish a long-term and stable cooperation relationship with customer in the world.

Company Info
  • Business Type: Manufacturer
  • Product Range: Additive , Chemical Auxiliary & Catalyst , Organic Chemicals
  • Products/Service: Organic Intermediate,Inorganic Chemistry, APIs, Dyestuffs And Pigments, Fragrance And Spices, Food Additives
  • Total Employees: 51~100
  • Capital (Million US $): 10000000RMB
  • Year Established: 2016
Production Capacity
  • No. of Production Lines : 8
  • No. of QC Staff : 5 -10 People
  • OEM Services Provided : yes
  • Factory Size (Sq.meters) : 3,000-5,000 square meters
  • Certificate: ISO9001 , CE , GMP , API , MSDS
  • Factory Location : Diao Town Industry Park, Zhangqiu City, Jinan City, Shandong Province, China.


Pre-Sales Service

* Prompt reply and 24 hours online, professional team to provide best price and high quality product.

* Sample testing support.

* Every batch of products will be tested to ensureits quality.

*The packing also can be according the customers` requirment.

*Any inquiries will be replied within 24 hours.

*we provide Commerical Invoice, Packing List, Bill of loading, COA , Health certificate and Origin certificate. If your markets have any special requirements, let us know.


After-Sales Service

*The fact of logistics information monitoring.

* Any questions about the product can be consulted at any time.

*Product has any problem can return.


Do you accept sample order?

We will make samples before mass production, and after sample approved, we’ll begin mass production. Doing 100% inspection during production, then do random inspection before packing.



You can get free samples for some products,you only need to pay the shipping cost or arrange a courier to us and take the samples. You can send us your product specifications and requests,we will manufacture the products according to your requests.

What’s your MOQ?

Our MOQ is 1kg. But usually we accept less quantity such as 100g on the condition that sample charge is 100% paid.

Do you supply product report?

Yes. We’ll give you product analysis report before shipping.

  Is there a discount?

Different quantity has different discount.


1. ≤50kg, Express delivery recommended, usually called as DDU service;

2. ≤500kg, Air shipping recommended, usually called as FOB, CFR, or CIF service;

3. >500kg, sea shipping recommended, usually called as FOB, CFR, or CIF service;

4. For high value products, please select air shipping and express delivery for safe.

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