Microelectrode Array

January 20, 2012

Building Addressable Libraries: Amino Acid Derived Fluorescent Linkers

Takamasa Tanabe, Bo Bi, Libo Hu, Karl Maurer, and Kevin D. Moeller

Langmuir, 2012, 28 (3), 1689-1693

A new amino acid derived fluorescent linker for attaching molecules to the surface of a microelectrode array has been developed. Molecules to be monitored on an array are attached to the C-terminus of the linker, the N-terminus is then used to attach the linker to the array, and the side chain is used to synthesize a fluorescent tag. The fluorescent group is made with a one-step oxidative cycloaddition reaction starting from a hydroxyindole group. The linker is compatible with site-selective Cu(I)-chemistry on the array, it allows for quality control assessment of the array itself, and it is compatible with the electrochemical impedance experiments used to monitor binding events on the surface of the array.


January 20, 2011

Site-Selectively Functionalizing Microelectrode Arrays: The Use of Cu(I)-Catalysts

Jennifer Bartels, Peng Lu, Karl Maurer, Amy V. Walker, and Kevin D. Moeller

Langmuir, 2011, 27 (17), pp 11199–11205

Site-selective Cu(I)-catalyzed reactions have been developed on microelectrode arrays. The reactions are confined to preselected electrodes on the arrays using oxygen as the confining agent. Conditions initially developed for the Cu(I)-catalyzed click reaction have proven general for the coupling of amine, alcohol, and sulfur nucleophiles to both vinyl and aryl iodides. Differences between reactions run on 1-K arrays and reactions run on 12-K arrays can be attributed to the 1-K array reactions being divided cell electrolyses and the 12-K array reactions being undivided cell electrolyses. Reactions on the 12-K arrays benefit from the use of a non-sugar-derived porous reaction layer for the attachment of substrates to the surface of the electrodes. The reactions are sensitive to the nature of the ligand used for the Cu catalyst.


January 20, 2011

Site-Selective, Cleavable Linkers: Quality Control and the Characterization of Small Molecules on Microelectrode Arrays

Bi, Bo; Huang, Richard Y.-C.; Maurer, Karl; Chen, Ceng; Moeller, Kevin D.

Journal of Organic Chemistry 2011, 76(21), 9053-9059

A “safety-catch” linker strategy has been used to release a portion of the products of a Diels-Alder reaction conducted on a microelectrode array for characterization of stereochem.  The attachment and cleavage of org. compds. from the surface of selected electrodes in the array can be accomplished by site-selective generation of base or acid at the electrode.  It was found that the surface of the array had a minor influence on the stereochem. of the Diels-Alder reaction, leading to slightly more of the exo-product relative to a similar soln.-phase reaction.


November 23, 2010

Building Addressable Libraries: Site-Selective Use of Pd(0) Catalysts on Microelectrode Arrays

Libo Hu, Melissae Stuart, Jun Tian, Karl Maurer, and Kevin D. Moeller

J. Am. Chem. Soc., 2010, 132 (46), pp 16610–16616

Site-selective Pd(0)-catalyzed reactions have been developed to functionalize a microelectrode array. Heck, Suzuki, and allylation reactions have all been accomplished. The reactions are compatible with both 1K and 12K arrays and work best when a nonsugar porous reaction layer is used. Suzuki reactions are faster than the Heck reactions and thus require more careful control of the reactions in order to maintain confinement. The allylation reaction requires a different confining agent than the Heck and Suzuki reactions but can be accomplished nicely with quinone as an oxidant for Pd(0).
October 29, 2009

A New Porous Reaction Layer for Developing Addressable Molecular Libraries

Libo Hu, Jennifer L. Bartels, Jeremy W. Bartels, Karl Maurer and Kevin D. Moeller

J. Am. Chem. Soc., 2009, 131(46), 16638–16639

A new diblock copolymer-derived porous reaction layer for microelectrode arrays has been tested for its stability and its compatibility with both site-selective synthesis and electrochemical signaling experiments. The diblock copolymer consisted of a cinnamoyl-substituted polymethacrylate block for attachment to the surface of the array and a bromo-substituted polystyrene block for selective functionalization of the surface proximal to microelectrodes in the array. Site-selective Suzuki, Heck, and Cu(I)-coupling reactions were all performed on the new reaction layer along with electrochemical impedance studies.