The method for extracting collagen from Vietnamese freshwater fish scales, by Dr. Nguyen Thuy Chinh and colleagues at the Institute of Tropical Technology, have been granted a proprietary utility solutions by the National Office of Intellectual Property No.2-0002775

From freshwater fish scales obtained from local markets, Dr. Nguyen Thuy Chinh and colleagues at the Institute of Tropical Technology (Vietnam Academy of Science and Technology) isolated and obtained clean and safe collagen as a source of raw materials to help stop bleeding, regenerate tissue and preparation of drugs to support the treatment of gout.

Fish scales are turned into collagen in the laboratory

Collagen has long been widely used in biomedical applications. However, most of the popular products in the market are derived from mammals, such as pigs, cows and sheep. The clinical application of these materials has long been somewhat limited due to cultural and religious influences related to materials of mammalian origin. In addition, concerns about the risk of transmission of infectious diseases from mammals also complicate the handling and inspection process.

Around the world, scientists have also had many works on extracting collagen from fish scales. Typically, in 2018, scientists from Nanyang Technological University, Singapore (NTU Singapore) announced that collagen extracted from the scales of sea bass, tuna and tilapia could bring great potential in the treatment of cancer and heal wounds. “Our other thing is to use the scales of freshwater carp species originating from Vietnam, not saltwater or brackish water as the studies have shown. Not only will biodiversity in each location affect the maturation of freshwater fish in different ways, but different temperatures also lead to different composition and composition of fish scales” – Dr. Nguyen Thuy Chinh explained.

In addition, the research team also aims to use the obtained collagen as a carrier for the treatment of reducing uric acid in the blood and as a material for tissue regeneration and wound healing. From the mixture of fish scales obtained from people's markets in Hanoi, Vinh Phuc, etc., the research team washed, dried and then soaked in alkaline to remove fat on the surface. The mackerel scales from the above process are soaked in a mixed acid-base solution for 8 hours using a mechanical stirrer combined with high-speed ultrasonic stirring to remove protein and impurities. To separate minerals from fish scales, the team continued to soak the resulting mixture in acid at a volume ratio of 1: 2 and then mechanically stirred for 20 minutes.

Continue to soak fish scales in acetic acid solution for 24 hours with a mechanical stirrer combined with high-speed ultrasonic stirring. Filter to obtain a collagen solution in acetic acid. Add solid NaCl to the above solution and proceed to cool to collect collagen and then extract by separating funnel. The crude collagen was further dissolved in acetic acid, crystallized a second time with solid NaCl, and then dialysis was carried out by membrane dialysis for 48 hours to obtain pure collagen in gel form. If you want to dry, put collagen gel at -200C to get dry, spongy, ivory-white collagen.

One of the team's findings during the extraction process was that collagen extraction from fish scales was completely affected by temperature. At the first stage when conducting extraction under normal temperature conditions, the research team often falls into the situation of "sometimes it can't be separated" or the quality of batches is not uniform. Observing the experiments, the team found that when extracted in winter, the amount of collagen obtained was higher than in summer. Due to higher summer temperatures, most of the collagen converts to gelatin, resulting in low yield and no collagen in batches. Dr. Chinh excitedly said: "After this discovery, the entire extraction process was carried out in a thermostatic bath with a temperature of 40C, helping to stabilize the collagen collection process and not change its properties."

The obtained collagen has a fibrous structure, the fiber diameter is 0.5-1 micrometer, the collagen fibers are concentrated into fiber bundles, 2.5-4 micrometers in size. The representative of the research team said that this is characteristic of type 1 collagen, a common type of collagen in the human body and very important for wound healing, creating elasticity, elasticity and keeping the connection among tissues together.

Currently, the research team is completing the project so that it can be combined with businesses towards developing a product to help stop bleeding from this material.

ctngoc