Its characteristics mainly include the following aspects:

Cell culture medium is an artificial simulation of the nutritional environment in which cells grow in vivo. It provides essential nutrients, regulatory substances, etc. for cells to support their growth, proliferation, and metabolism. Its characteristics mainly include the following aspects:

Rich in Nutritional Components

• Basic Nutrients: It contains the basic nutritional components required for cell growth, such as amino acids, carbohydrates, vitamins, and inorganic salts. Amino acids are the raw materials for cells to synthesize proteins. Different cells have different demands for various amino acids, and the medium usually contains a variety of essential and non-essential amino acids. Carbohydrates provide energy for cells, and glucose is a common example. Vitamins participate in various metabolic reactions within cells, such as the B-vitamin complex. Inorganic salts play an important role in maintaining the osmotic pressure and acid-base balance of cells, as well as the activity of intracellular enzymes.
• Special Nutritional Factors: In addition to basic nutrients, some culture media are also supplemented with special nutritional factors, such as growth factors and hormones. Growth factors can promote cell growth, proliferation, and differentiation. Different types of cells require different growth factors, such as epidermal growth factor (EGF), fibroblast growth factor (FGF), etc. Hormones also play an important regulatory role in the growth and differentiation of cells, such as insulin, hydrocortisone, and so on.

Strong Buffering Capacity

Cells produce metabolic products during growth, such as carbon dioxide and lactic acid. These metabolic products can affect the acidity and alkalinity of the culture medium. Cell culture medium usually has a good buffering capacity, which can resist changes in acidity and alkalinity and maintain an appropriate pH environment for cell growth. Common buffering systems include the phosphate buffering system and the HEPES buffering system. The phosphate buffering system can maintain the pH stability of the medium within a certain range, while the HEPES buffer solution has a stronger buffering capacity and can remain stable within a wider pH range, especially suitable for cells cultured in a carbon dioxide incubator.

High Sterility

• Strict Production Process: The production process of cell culture medium needs to be carried out under strict aseptic conditions. From the procurement of raw materials, preparation to packaging, every link should be strictly controlled for quality and detected for microorganisms to ensure that the medium does not contain microorganisms such as bacteria, fungi, viruses, and mycoplasma.
• Addition of Antibacterial Components: To further prevent microbial contamination, an appropriate amount of antibiotics or bacteriostatic agents may be added to some culture media. However, when using a medium containing antibiotics, attention should be paid to its potential impacts on cells, such as affecting cell growth, metabolism, and gene expression. Therefore, in routine cell culture, it is generally not recommended to use a medium containing antibiotics for a long time.

Diverse Applicability

• For Different Cell Types: According to the growth characteristics and nutritional requirements of different cells, various types of cell culture media have been developed. For example, Dulbecco’s Modified Eagle Medium (DMEM) is suitable for the culture of a variety of mammalian cells, Roswell Park Memorial Institute (RPMI) 1640 medium is often used for the culture of immune cells such as lymphocytes, and Medium 199 is widely used for the culture of chicken embryo cells, etc.
• Meeting Different Culture Purposes: In addition to the media for different cell types, there are also some culture media for special purposes, such as serum-free media and protein-free media. Serum-free media can reduce the influence of uncertain factors in serum on cell culture and are suitable for fields with high requirements for cell culture conditions, such as cell biology research and biopharmaceutical production. Protein-free media are mainly used for the culture of certain cells with strict requirements for protein content, such as the production of recombinant proteins.

Good Physical Properties

• Appropriate Osmotic Pressure: The osmotic pressure of the culture medium is crucial for cell growth and survival. Too high or too low osmotic pressure will affect the morphology and function of cells, and may even lead to cell death. Different types of cells have different requirements for osmotic pressure. Generally, the osmotic pressure of the culture medium for mammalian cells is between 260 – 320 mOsm/kg.
• Suitable Viscosity: The viscosity of the culture medium mainly affects the mass transfer and hydrodynamic characteristics of cells. An appropriate viscosity can ensure the uniform distribution of cells in the medium, which is beneficial to the transfer of nutrients and the excretion of metabolic products. Usually, the viscosity of cell culture medium is relatively low to facilitate cell growth and metabolism.