Print-and-Peel Protein Arrays

Just came across two variations on print-and-peel methods for making protein arrays. First is the article in Nature Chemistry on using thiol-ene chemistry for making protein arrays. In its first incarnation, you spot your favorite proteins/peptides in an array format on a glass substrate. Cover the spotted substrate with a liquid polyethylene glycol (PEG) polymer consisting of a four armed PEG polymer with cysteine end groups, PEG polymer with alkyne end groups and an initiator (Ex. DMPA). Gently shining UV light will cure the PEG pre-polymer into a hydrogel by crosslink PEG polymers and spotted proteins/peptides (through their cysteine residues) using thiol-ene chemistry. Peeling off the cured hydrogel will lift-off the printed proteins/peptides from glass and transfer it to PEG hydrogel film. Voila! You have a protein/peptide array on a PEG hydrogel. In its second incarnation, instead of spotting proteins/peptides you can spot small heterobifunctional crosslinker with alkene at one end and your favorite reactive group (NHS ester, azide, aldehyde etc.) on another. Replay the trick with making a PEG hydogel and peel off the polymer to have an array of reactive groups that can be used for binding any biomolecule. Instead of spotting proteins/peptides, crosslinker or fluorophore individually, mix them to have orthogonal reactivities.

Second paper on similar theme came out in Biosensor and Bioelectronics titled “Protein pattern transfer for biosensor applications”. Here you print/pattern protein on a silicon substrate (glass could be used too- I guess), apply a thin layer (3-5nm) of trehalose sugar coating by spin coating. Sugar layer prevents proteins from denaturing in subsequent steps. Add a thin layer of siloxane using plasma deposition. Add some glue on top and stick another substrate on top. Top substrate can be anything from plastic, to anything else. Peel gently and the printed protein/pattern comes off and you have a substrate with patterned proteins.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s