Reagents and supplements

Cell culture refers to growing cells outside their natural environment. For peak cell proliferation, it’s important to maintain optimal cell culture conditions inside a suitable vessel with the right medium. A cell culture medium is a liquid or gel formulation that supports the growth of cells. Media formulations often have amino acids, buffers, vitamins, hormones, inorganic salts, and other factors. Culture media also regulate physiochemical parameters like pH and osmolality. Supplementing media with specific cell culture reagents can improve cell growth and increase the length of culture.

What are cell culture reagents?

Cell culture reagents support the isolation, growth, and processing of cells. They include a wide variety of reagents – antibiotics, density gradient media, feeds, cell culture supplements like growth factors, and more.

Contamination in cell culture

Contamination is a key challenge faced by lab researchers and bioprocessing scientists. Following strict aseptic techniques limits the risk of contamination, as does closed processing in a manufacturing environment. Antibiotics may be added to target and kill biological contaminants such as bacteria cells.

Cell separation through density gradient centrifugation

Cell separation separates specific cell types from a mixed population of cells. One way to do that is by density gradient centrifugation, which separates cells by density. A common application is in blood processing, to obtain a particular blood fraction. Because density gradient media don’t affect biological activity, they are well-suited to purification of cells and organelles.

Cell culture supplementation

Cell culture supplements are cell culture reagents added to keep cell s viable and growing to a higher density than would otherwise be possible. A wide variety of supplements are available to meet the metabolic needs of different cell lines. Some options are sodium pyruvate, cholesterol supplements, specific growth factors, amino acids, and concentrated vitamins.

Fed-batch culture

One way to maximize cell density in bioprocessing is by adding feed supplements at specific times throughout culture. This processing mode, called fed batch, extends the duration of the culture to increase production of the biologic of interest.

Cell dissociation

Adherent cells, which include cell lines used in research and biomanufacturing, need attachment substrates like a tissue culture flask or microcarriers for peak culture. These anchorage-dependent cells often require dissociation or disaggregation to detach them from the surface on which they’re growing. This is usually accomplished by cell culture reagents called cell dissociation reagents, which include porcine trypsin and recombinant enzymes produced in microbial systems. The latter is preferred when manufacturing biologics to avoid introducing an animal-derived component.

Cryopreservation of cell lines

Cryopreservation is the process of preserving tissues, cells, and other biological constructs by cooling samples to extremely low temperatures. There are several reasons to cryopreserve mammalian cells. Among these is mitigating loss by contamination and reducing the risk of genetic changes in cell lines. Cryopreservation can also maintain cells for long-term storage and transportation between sites.

Cryopreservation media contain a cryopreservative that protects cells from the stress caused by the freezing and thawing process. DMSO is often used for this purpose, in a cell culture medium or similar component that may or may not include protein.