RSC Publishing


Publishing

 

Cover image for The Analyst, select for current issue

The Analyst

The home of high impact research in analytical, bioanalytical and detection science.




Paper

Analyst, 2006, 131, 1097 - 1104, DOI: 10.1039/b607180e


Photocleavable peptide hydrogel arrays for MALDI-TOF analysis of kinase activity

Laurie L. Parker, Shawn B. Brueggemeier, Won Jun Rhee, Ding Wu, Stephen B. H. Kent, Stephen J. Kron and Sean P. Palecek


We have developed an acrylamide copolymerization strategy to immobilize acrylamide labeled peptides and proteins into a hydrogel surface and detect their modifications using MALDI-TOF mass spectrometry. Copolymerization into hydrogels is robust, compatible with off-the-shelf chemistry, and yields materials and surfaces that are stable to aqueous or organic solvents, drying, high or low temperature, high or low pH, oxidizing agents, sonication, mechanical contact, etc. The use of acrylamide hydrogels allows immobilization of substrates in a hydrated environment that can be used both as a biological reaction matrix and as a MALDI target. In our strategy, a substrate peptide was designed in a modular fashion to include both modification site and affinity domains. It was labeled with an acrylamide functionality using a generalized chemistry and covalently attached to the surface with a photocleavable linker, allowing for aggressive washing to remove any fouling, followed by selective release for MALDI-TOF analysis. Using this system we were able to analyze and compare v-Abl (truncated) and c-Abl (full-length) kinase activity on a peptide substrate with an affinity domain specific for the full-length kinase, observing excellent overall reproducibility in the extent of phosphorylation detected. This work serves as proof of principle for modular substrate design strategies for mass spectrometry-readable biosensors.

Graphical abstract image for this article  (ID: b607180e)