LONG® EGF is a recombinant analogue of human epidermal growth factor (EGF) developed as a supplement for use in therapeutic cell culture applications as a like for-like replacement for native EGF or recombinant human EGF (rhEGF). It comprises the human EGF amino acid sequence plus a 53 amino acid N-terminal extension peptide.

LONG® EGF has applications in MSC, iPS, epithelial, fibroblast, HEK293, BHK-21, and MDCK cell lines. LONG® EGF may also exhibit synergistic effects with LONG® R3 IGF-I in certain cell lines.


Yes. LONG® EGF is manufactured according to cGMP standards. The production facility is regularly audited by European and US contract manufacturers and biopharmaceutical companies.

LONG® EGF is regulatory compliant and is currently used in the manufacture of regulatory approved and marketed cell therapies.

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No. LONG® EGF is a cGMP grade recombinant protein produced in E. coli. It is specifically manufactured for mammalian cell culture using a process that is free of animal-derived components.


The recommended concentration range is 10 - 50 μg/l. The maximum should not exceed 100 μg/l and generally lower concentrations work better than higher ones. As a starting point, we recommend developing a media with 50 μg/l.


We do not recommend dissolving freeze-dried formulations in media.


Concentrations of 1mg/ml or more are recommended.


As with all peptides, LONG® EGF can stick to plumbing and filters in the absence of other protein components. We recommend that the supplemented media be sterile filtered with a low protein binding filter prior to use.

  1. Perform all activities in a controlled environment such as a laminar flow cabinet using aseptic techniques.
  2. Care should be taken when opening the vial to equilibrate the contents with ambient pressure.
  3. An air-filled syringe may be introduced through the stopper to equalize the pressure before opening.
  4. Reconstitute the vial to the recommended concentration of 1 mg/ml in 10 mM HCl.
  5. Irrespective of the vial size, always reconstitute the entire vial in situ. Do not estimate the protein content by weight or gravimetric means as this will underestimate the actual protein content due to the residual moisture retained through the freeze-drying process.
  6. Dilute further to 0.1 mg/ml using 10 mM HCl to achieve the working stock solution. Do not use phosphate buffered saline (PBS) or a buffer containing phosphate to dilute to the working stock as this can cause the protein to precipitate out of solution.
  7. Subsequent dilutions can be made in PBS or other buffered solutions including cell culture media.
  8. If filtration is required, it is recommended to perform this using the 1 mg/ml or 0.1 mg/ml working stock solution and low-protein binding filter membranes to avoid any non-specific binding of the protein during filtration.