Bovine Serum Albumin (BSA) is commonly used to stabilize some proteins during reactions, and can also prevent adhesion to reaction tubes and pipette surfaces. We understand that there is an increased need for comparable performance using BSA-free reagents. NEB has switched our current BSA-containing reaction buffers (NEBuffer 1.1, 2.1, 3.1 and CutSmart® Buffer) to Recombinant Albumin-containing buffers (NEBuffer r1.1, r2.1, r3.1 and rCutSmart™ Buffer). We are also in the process of moving all restriction enzyme formulations to contain rAlbumin. We feel that moving away from animal-containing products is a step in the right direction and are able to offer this enhancement at the same price.

What does this mean for you?

NEB has rigorously tested both and has not seen a difference in enzyme performance when using either buffer. Either buffer can be used with your enzyme. All website content has been switched to reflect the changes.

Key points to remember


  • Use of rAlbumin in reaction buffers enables them to be used in situations where BSA-free reagents are required
  • There is no difference in enzyme performance when using buffers containing BSA and buffers containing rAlbumin
  • If you have a buffer containing rAlbumin, we recommend using it, but you can also continue to use buffers containing BSA if “BSA-free” is not a requirement
  • NEB offers the NEBuffer Set (r1.1, r2.1, r3.1 & rCutSmart Buffer), NEBuffer r2.1, NEBuffer r3.1, and rCutSmart Buffer if you wish to purchase these buffers separately
  • If you have any questions, please contact us at


What is Recombinant Albumin (rAlbumin)?

Recombinant Albumin (rAlbumin) (NEB #B9200) is a non-bovine derived albumin that can serve as an alternative to Bovine Serum Albumin
(BSA). Like BSA, it has been shown to prevent adhesion of enzymes to reaction tubes and pipette surfaces. It also stabilizes some
proteins during incubation. Choose Recombinant Albumin when there is a need to avoid BSA.

Why has NEB switched to buffers containing Recombinant Albumin (rAlbumin)?

In addition to being animal-free, a recombinant source of albumin offers increased consistency and purity. It eliminates sources of contamination and decreases lot-to-lot variability.

Is there a performance difference between buffers and enzyme formulations containing BSA and buffers containing Recombinant Albumin (rAlbumin)?

NEB has rigorously tested the performance between BSA- and rAlbumin-containing buffers and enzyme formulations (NEB #B9200). We have not seen a difference in enzyme performance when using either. Rest assured, you can continue to use either version for your experiments.

ClaI (NEB #R0197) restriction endonuclease was formulated with BSA or Recombinant Albumin (rAlbumin). Each of these formulations was tested using either A. CutSmart (contains BSA) or B. rCutSmart (contains rAlbumin) Buffer. Serial dilutions of ClaI were tested using Lambda DNA and the recommended assay conditions, followed by analysis using agarose gel electrophoresis. M is marker 1 kb Plus DNA Ladder (NEB #N3200). ClaI activity is the same in all formulation conditions tested. These representative data demonstrate equal performance between BSA and rAlbumin when used in both enzyme formulation and reaction buffer.

Should I only be using buffers containing Recombinant Albumin (rAlbumin)?

NEB has switched all NEBuffers with BSA to contain rAlbumin (NEB #B9200). There is no difference in enzyme performance when using either buffer, so we recommend using whichever buffer is included with your enzyme.  

Can I continue to use the reaction buffers containing BSA?

Yes, since there is no difference in enzyme performance when using NEBuffers containing BSA or Recombinant Albumin (rAlbumin) (NEB #B9200), you can continue to use buffers containing BSA. NEB will no longer supply BSA-containing buffers.

Can I purchase buffers containing Recombinant Albumin (rAlbumin) separately?

Yes, NEBuffer Set (r1.1, r2.1, r3.1, rCutSmart) (NEB #B7030) can be purchased separately. This product contains one vial of each rAlbumin-containing buffer. You can also purchase NEBuffer r2.1 (NEB #B6002), NEBuffer r3.1 (NEB #B6003) or rCutSmart Buffer (NEB #B6004) which contains 4 vials of each designated buffer. In addition, Recombinant Albumin (NEB #B9200) is available as a stand-alone product.



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Please feel free to contact us with questions about this buffer change.