PuraMatrix® is the first commercial synthetic extracellular matrix (ECM) scaffold, enabling cells to be cultured in carefully controlled microenvironments for life science research, pharmaceutical drug discovery and bioproduction. PuraMatrix® enhances valuable and expensive cell assays that predict proper drug interactions and metabolism. In particular, PuraMatrix® has improved cell assays in which one or more types of cells form complex structures (such as spheroids, networks, synapses, vascularization). The result is improved models for in vivo and in vitro research and testing, increasing predictability and reducing the cost of drug discovery research. Click here to review PuraMatrix® Guidelines for Use.
Q. Why is it necessary to work quickly when mixing cells with this material prior to gelation?
A. The stock solution of PuraMatrix® (1% w/v) has a pH of 2.0-3.0, which can limit cell viability. Therefore, it is important to work quickly to minimize the time cells are in contact with the material prior to the addition of culture medium. Changing the culture medium three times within the first 30 minutes equilibrates the sample to physiological pH.
Q. What is the mechanical strength of PuraMatrix®?
A. At the typical working concentration (0.5% w/v), PuraMatrix® forms a soft fibrous network of relatively weak mechanical strength. This feature has important benefits for cell migration, spheroid formation, and angiogenesis. Therefore, it is necessary to handle the material very carefully when performing medium changes (i.e., avoid direct contact with the hydrogel when using pipet or aspiration tips). Importantly, the 0.5% hydrogel has been found to promote the attachment and growth of many cell types. To prepare a hydrogel with greater mechanical strength, the material can be used in the undiluted form (1% w/v).
Q. What is the best way to remove air bubbles which may result from mixing PuraMatrix® with cells, bioactive molecules, and/or medium?
A. Air bubbles can be removed by sonication in a bath sonicator for 30 minutes or by centrifugation (e.g., spin two to five minutes at 5K in a tabletop centrifuge). If small volumes are used in a 1.5 ml Eppendorf tube, centrifugation can be performed using an Eppendorf microfuge for 10-15 seconds at full speed.
Q. Since the peptide sequence of PuraMatrix® is similar to RGD (arginine-glycine-aspartate), do cells bind to the material via RGD-dependent integrin receptors?
A. No. The peptide sequence promotes cell attachment, but does not mediate RGD-dependent integrin signaling. Studies have shown that cell attachment is not inhibited by RGD-containing peptides.