Preparing Protein Microarrays by Soft-Landing of Mass-Selected Ions
Zheng Ouyang,1
Zoltán Takáts,1
Thomas A. Blake,1
Bogdan Gologan,1
Andy J. Guymon,1
Justin M. Wiseman,1
Justin C. Oliver,2
V. Jo Davisson,2
R. Graham Cooks1*
Intact, multiply protonated proteins of particular mass and
charge were selected from ionized protein mixtures and gently
landed at different positions on a surface to form a microarray.
An array of cytochrome c, lysozyme, insulin, and apomyoglobin
was generated, and the deposited proteins showed electrospray
ionization mass spectra that matched those of the authentic
compounds. Deposited lysozyme and trypsin retained their biological
activity. Multiply charged ions of protein kinase A catalytic
subunit and hexokinase were also soft-landed into glycerol-based
liquid surfaces. These soft-landed kinases phosphorylated LRRASLG
oligopeptide and D-fructose, respectively.
2 Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA.
* To whom correspondence should be addressed. E-mail: cooks{at}purdue.edu
