FAQs2019-09-07T15:29:31+00:00

FAQ

Sterility of protein stock solutions2019-09-08T20:41:42+00:00

Every effort is made to ensure samples are sterile however we recommend sterile filtering after dilution in media or the final working solution

Handling guidance for lyophilised cytokines including Activins, BMPs and GDF152019-10-14T11:48:03+00:00

TGF beta family proteins and other growth factors can be very poorly soluble in physiological solutions.  Please follow the handling guidance for lyophilised cytokines below to minimise loss of protein due to precipitation or adsorption to plastic.  We advise storing the recombinant protein at very low pH to before dilution in cell culture media or final working solutions. Low pH will also assist in maintaining the correct disulphide structure of the protein by minimising disulphide bond exchange reactions.

  • Resuspension in physiological buffers may cause precipitation of stock solutions, hence we recommend dissolving our lyophilised cytokines in 10 mM HCl (1:1000 dilution of concentrated HCl) while keeping the protein concentration at 50 µg/ml or above, in order to avoid loss by adsorption to plasticware.
  • To ensure you recover all of the protein, let the sample sit for a few minutes with the solubilisation buffer at room temperature and pipette gently up and down (avoid foaming).
  • Rinse the tube with some more 10 mM HCl and pool with the rest.
  • The protein is tolerant of some freeze and thaw cycles, but as always with proteins, it is better to aliquot and stored frozen.
  • Our protein are supplied carrier-protein free.  If compatible with your work, add carrier protein of your choice such as BSA, HSA or gelatin to further minimise loss by adsorption.
  • Store in -80°C for long term storage. -20°C for short-term.

Every effort is made to ensure samples are sterile however we recommend sterile filtering after dilution in media or the final working solution