Cell culture medium liquid

Definition and Overview

Cell culture medium liquid is a mixture of liquid nutrients specially formulated to support cell growth, proliferation, differentiation and other activities in an in vitro environment. It aims to simulate the natural microenvironment where cells are located in vivo as much as possible and provide the necessary conditions for the survival and normal physiological functions of cells, enabling cells to grow stably and carry out various metabolic activities even when separated from living organisms.

Specific Applications

• Scientific Research Experiments: It is widely used in basic life science research. For example, in the field of cell biology, it can be used to culture various types of cells, such as mammalian cells (such as mouse embryonic fibroblast cells, human cancer cell lines, etc.), insect cells (used in research related to insect viruses, etc.) and microbial cells (bacteria, yeasts, etc.). By observing the growth morphology, proliferation rate, migration characteristics, etc. of cells in the liquid culture medium, in-depth exploration of the basic physiological processes, gene functions, signal transduction mechanisms and other aspects of cells can be carried out. In molecular biology research, it is convenient for researchers to extract biological macromolecules such as DNA, RNA and proteins from cultured cells, and then conduct gene expression analysis, evaluation of the effects of gene editing, proteomics research and other work.
• Biopharmaceutical Industry: It is the key basic material for the production of various biological products. In terms of antibody production, it provides nutrition for hybridoma cells or genetically engineered cells, enabling them to synthesize and secrete monoclonal or polyclonal antibodies in large quantities. These antibodies can be used for disease diagnosis, treatment and immunological related research. For vaccine production, many viral vaccines (such as polio vaccines, measles vaccines, etc.) need to first culture the corresponding viruses in a suitable cell culture medium liquid, and then undergo inactivation, attenuation and other processes to make the finished vaccines. In addition, in the field of gene therapy, liquid culture media are used to culture cells that produce viral vectors (such as adeno-associated virus vectors, lentivirus vectors, etc.) or non-viral vectors carrying therapeutic genes, helping to accurately deliver the therapeutic genes into patients’ bodies.
• Cell Therapy Field: Both stem cell therapy and immune cell therapy rely on cell culture medium liquid. In stem cell culture, embryonic stem cells, mesenchymal stem cells, induced pluripotent stem cells, etc. rely on suitable liquid culture media to maintain their self-renewal ability and multi-directional differentiation potential. After culture and expansion, they can be applied to the treatment of various diseases such as neurological diseases, cardiovascular diseases, orthopedic diseases, etc. In immune cell therapy, for example, in CAR-T cell therapy, T cells are activated, expanded and undergo CAR (chimeric antigen receptor) gene transduction in a specific liquid culture medium, and finally generate CAR-T cells with strong tumor-killing ability, which are used for the treatment of hematological tumors and some solid tumors.
• Clinical Diagnosis Purposes: It plays a role in detecting pathogens. Patient samples suspected of containing pathogens (bacteria, fungi, viruses, etc.) can be inoculated into specific cell culture medium liquids. According to the characteristics of pathogen growth and reproduction in them (such as colony morphology, changes in the turbidity of the culture solution, cytopathic effects, etc.), the types of pathogens can be identified, assisting doctors to accurately determine the source of infection and formulate precise treatment plans. Meanwhile, for some tumor diseases, tumor cells of patients can also be collected and cultured in the liquid culture medium to conduct drug sensitivity tests to understand the sensitivity of tumor cells to different chemotherapy drugs and provide a reference for clinical medication.

Characteristics and Advantages

• Diversity and Precision of Components: It contains a variety of nutritional components, such as amino acids (providing raw materials for cells to synthesize proteins, including essential and non-essential amino acids), sugars (common glucose as the main energy source), vitamins (participating in numerous metabolic reactions in cells and acting as coenzymes, etc.), inorganic ions (macronutrient ions such as sodium, potassium, calcium, and magnesium regulate osmotic pressure and participate in cellular physiological activities, and micronutrient ions such as iron, zinc, and copper have important effects on enzyme activities, etc.). Moreover, the concentrations of these components are precisely adjusted according to the requirements of different cell types to ensure that cells can obtain the most suitable nutrient supply.
• Good Physicochemical Properties: It has an appropriate osmotic pressure, usually similar to that inside the cells, to avoid excessive water absorption or loss by the cells and damage to them. It has good pH buffering capacity. The sodium bicarbonate/CO₂ buffer system or the addition of HEPES buffer is often used to stably maintain the pH value within a range suitable for cell growth (usually around 7.2 – 7.4), ensuring that biological macromolecules such as enzymes in the cells can function normally. In addition, the liquid state facilitates the uniform dispersion of cells in it, which is beneficial for cells to fully contact nutrients and promote growth.
• Customizability and Adaptability: It can be customized according to different cell lines, culture purposes and specific experimental or production requirements. For example, specific growth factors (such as epidermal growth factor to promote the growth of epithelial cells, platelet-derived growth factor to help the proliferation of mesenchymal cells, etc.) and hormones (insulin to regulate the uptake and utilization of sugar by cells, etc.) can be added to meet the growth needs of special cells. At the same time, it can also adapt to different scale and condition application scenarios from small-scale laboratory culture to large-scale industrial production.
• Quality Controllability and Stability: In the production process of formally produced cell culture medium liquid, there are strict quality control links to ensure that the components, performance, etc. of each batch of products are relatively stable, reducing the interference of differences in the quality of the culture medium on the results of cell culture. Researchers and production personnel can relatively accurately predict the results of cell culture based on the quality standards of the products.

Precautions for Use

• Storage Conditions: Generally, it needs to be stored in a low-temperature (usually 2 – 8 °C), dark environment to avoid the decomposition, deterioration or microbial growth of nutritional components caused by high temperature and light. Some special culture medium liquids may also need to be frozen for storage. Before use, they should be thawed according to the specified procedures, and they should not be frozen again after thawing to prevent affecting their performance.
• Pre-use Inspection: Before use, carefully check the appearance of the culture medium liquid to see if there is any abnormal phenomenon such as turbidity, precipitation or discoloration. If any of the above situations occur, it is likely that the culture medium has been contaminated or deteriorated and should not be used. At the same time, check the name, batch number, expiration date and other information of the culture medium to ensure that the correct and qualified product is used.
• Aseptic Operation: Since cell culture has strict requirements for the environment, during operations such as adding culture medium liquid and inoculating cells, the principle of aseptic operation must be followed. Operators should wear sterile clothes, gloves, masks, etc., use sterilized instruments (such as pipettes, culture dishes, cell culture flasks, etc.), and operate in a sterile environment such as a sterile laminar flow bench to prevent external microorganisms from mixing into the culture medium and contaminating cell culture, which will affect the results of experiments or production.
• Inoculation Density Control: When inoculating cells into the culture medium liquid, pay attention to controlling the appropriate inoculation density. Different types of cells have different requirements for the initial inoculation density. An overly high inoculation density may lead to problems such as insufficient growth space for cells, rapid depletion of nutrients, and excessive accumulation of metabolic wastes, affecting the normal growth and function of cells. While an overly low inoculation density may cause slow cell growth or even difficulty in normal proliferation, prolonging the culture period.
• Monitoring during the Culture Process: During the cell culture period, it is necessary to regularly observe the growth state of the cells (such as whether the cell morphology is normal, whether there are floating dead cells, etc.) and the changes in the culture medium liquid (such as color changes, turbidity changes, etc.). Based on this feedback information, adjust the culture conditions in a timely manner, such as replacing fresh culture medium liquid in a timely manner and adjusting parameters such as the temperature and CO₂ concentration of the incubator to ensure that the cells are always in a good growth environment.

In conclusion, cell culture medium liquid has important applications in multiple fields. Understanding its characteristics and mastering the correct usage methods are crucial for ensuring the success of cell culture and the smooth progress of subsequent related research, production and other work.