FAQs for Recombinant Proteins

2021-10-15Author:adminpraise:0

1. Packaging and transportation



1)Can the protein be delivered in lyophilized form? Can you deliver liquid form?
In general, recombinant proteins are provided as lyophilized powder, bulk packages are provided as frozen liquid. Some of the proteins that cannot be lyophilized are also provided as frozen liquid.

2)What are the transport conditions of the protein?
In general, lyophilized recombinant proteins are shipped with ice packs. Frozen liquid proteins are shipped with blue ice unless customers require otherwise.

3)Recombinant protein has been shipped in transit for several weeks, and the ice/blue ice packs have melted when package been received, can the protein still be used in experiment?
Proteins as lyophilized form are relatively stable and can be used in experiment as normal. Proteins as frozen liquid form need to be tested before use. It is recommended to perform an SDS-PAGE test to confirm the condition of protein. If the protein is not degraded, and the purity and concentration meet the specifications, the protein can be used in experiment.


2. Storage conditions/stability



1)What are the recommended storage conditions for protein?
The protein as lyophilized form can be stored at -20 to -80°C for 12 months since the date of receipt. The protein as frozen liquid form can be stored at -20 to -80°C for 6 months since the date of receipt. Please avoid repeated freezing and thawing.

2)How long can the protein be kept at room temperature?
It is not recommended that the proteins to be kept at room temperature. In general, lyophilized protein can be stored at room temperature for 2-3 days, and liquid protein for less than 24 hours.


3.Technical matters

1)Is animal component free (ACF) protein available?
All recombinant proteins on sale are Animal Component Free proteins. Our recombinant protein does not contain any products directly derived from animals or human.

2)Can you provide natural purified protein?
Currently, Elabscience does not provide natural proteins.

3)Can your protein be used for cell culture/injection of animal?
Elabscience provides recombinant proteins that be used for cell culture or injection of animal. Generally speaking, proteins with an endotoxin content of less than 0.1 ng/ug (1 EU/ug) can be used in cell culture/injection animal.

4)Can your protein be used for Elisa kit development?
The on sale recombinant proteins can be used to develop Elisa assay. If binding activity is not mentioned in the protein specification, the customer may need to explore the reaction conditions themselves.

5)Can your proteins be used as an Immunogen?
The on sale recombinant proteins can be used as an Immunogen.

6)What solution can be used to dilute recombinant protein?
As lyophilized protein, it is recommended to reconstitute the lyophilized powder to a stock solution refer to hardcopy manual, then dilute with buffer as your experiment needed. As liquid protein, just dilute into target concentration with buffer as your experiment needed.

7)Has the protein been sequenced after it is expressed?
The Recombinant protein was not sequenced directly. But we sequenced the protein expression plasmid, and only if the sequence of target gene is correct can the protein be manufactured.

8)Can you please advise whether any virus or viral vector was used in the expression of the protein that expressed in Eukaryotic expression system?
No virus or viral vector was used in the expression of the protein that expressed in Eukaryotic expression system.

9)How is the protein purified?
Generally, recombinant protein was purified by affinity chromatography with the label, including nickel column/His Tag and protein G/Fc tag. The unlabeled proteins were purified by affinity chromatography first and then removed label.

10)What does "AP Mol Mass" mean? When I calculate molarity, should I consider "Mol Mass" or "AP Mol Mass"?
"AP Mol Mass" means apparent molecular weight, it is measured by SDS-PAGE. "Moll Mass" means theoretical molecular weight, it is calculated by direct translation of coding sequence. It is quite normal that the apparent molecular weight of a protein is not the same with the theoretical molecular weight. There are complex post-transcriptional modifications of mRNA and post-translational modifications of proteins that result in changes in apparent molecular weight. When calculate molar concentration you should take into account Mol Mass.