What is the standard for judging good fetal bovine serum?
Exterior Good serum should be clear and clear, khaki or brownish yellow, no precipitation or very little precipitation, relatively thick. If the serum is found to be turbid, opaque, contains many precipitates, indicating serum contamination or protein denaturation in serum; if brownish red, the hemoglobin content in the serum is too high, there is hemolysis. 2, total protein content The fetal bovine serum is generally in the range of 30-40 mg/ml, and the value is high, indicating that the cattle of the blood collection is too large, not the fetal calf ; the value is low, indicating that the serum may be mixed with water. 3, hemoglobin The standard is no higher than 20mg/dl, the redder the color, the higher the value; conversely, the lower the value. 4, pH Domestically produced serum, mostly above 7.5, imported fetal bovine serum, mostly below 7.5, the specific reasons are unknown, may be related to the age of cattle, which can also be used to initially identify the source of serum. microorganism Including bacteria, mold, mycoplasma, phage, various pathogenic viruses. With the improvement of the production conditions of domestic serum manufacturers, "large" microorganisms such as bacteria and mold can be controlled by 100%, and most of the mycoplasma can be removed by filtering through 0.1 μm. The contamination of E. coli phage is still relatively serious, mainly brought into the process of production environment, and can not be filtered, it is difficult to completely remove, but has little effect on serum quality. Pathogenic viruses, especially BVDV, exist in almost 90% of domestic serum. Such microorganisms are one of the important factors affecting the quality of domestic serum, and the detection rate of imported fetal bovine serum is not high compared with domestic serum. 6, immunoglobulin The domestic serum is only qualitatively tested, and the results are also very inaccurate. Most of the imported fetal bovine serum is quantitatively detected. The value of immunoglobulin can fully reflect the age of cattle at the time of blood collection . Domestically produced serum is basically newborn cattle. IgM is easily produced in serum, and the content of IgG is also high . Imported fetal bovine serum does not contain IgM or IgG. The content is also low. 7, antibiotic content In addition, the use of antibiotics is also taken into account. Serum at home and abroad is not tested for antibiotics (except for tetracycline-free fetal bovine serum). Among them, due to the strict use of foreign antibiotics, the amount is limited, and the products of each cow including serum can be traced back to the source, so the foreign fetal bovine serum does not contain antibiotics or the content is extremely low. However, due to the widespread use of antibiotics in China, the residual amount in serum is very high, resulting in poor quality of domestically produced serum, which is not conducive to cell culture. Serum source Serum blood sources in the market are mainly divided into China, North America, South America and Australia. The Australian sera, mainly from New Zealand and Australia, entered the Chinese market after the North American serum embargo, and generally did not have traceability. Among them, the Australian-based products in the Chinese market are mainly Ausbian serum. Ausbian sera, which has the reputation of “Best Cell Partnerâ€, has long been quietly popular in major laboratories. It selects serum batches with extremely low endotoxin and yields more than 1600 bottles (500 ml), which meets the requirements for stem cell, gene knockout, primary culture, cell collection, long-term passage and other cell culture requirements; complete test report and Anti-virus services provide complete support for the declaration of various clinical related projects. In 2014, the Ausbian serum trademark was registered with the China Trademark Office. Currently, this trademark is exclusively owned by Shanghai Weizheng Xiangsheng Biotechnology Co., Ltd. DC 3V With Lithium Battery Smoke Alarm Dc 3V With Lithium Metal Battery Smoke Alarm,Lithium Metal Alarm,Lithium Metal Smoke Alarm,Lithium Metal Battery Smoke Alarm Guangdong Isafenest Co.,Ltd. , https://www.isfenest.com
