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Karl Maurer

Publications and source records attributed to Karl Maurer.

7 recordsLinked to original sources
PubMed2006

Building addressable libraries: The use of a mass spectrometry cleavable linker for monitoring reactions on a microelectrode array.

Time-of-flight secondary ion mass spectrometry (TOF SIMS) has been used in conjunction with a mass spectrometry cleavable linker to determine the percent conversion of reactions that were conducted site-selectively on an addressable microelectrode array. When combined with fluorescence techniques for analysis of the reactions, the TOF SIMS experiment provides a means for optimization of both reaction confinement and reaction efficiency on the microelectrode arrays.

Calibration↗
PubMed2006

Electrochemically generated acid and its containment to 100 micron reaction areas for the production of DNA microarrays.

An addressable electrode array was used for the production of acid at sufficient concentration to allow deprotection of the dimethoxytrityl (DMT) protecting group from an overlaying substrate bound to a porous reaction layer. Containment of the generated acid to an active electrode of 100 micron diameter was achieved by the presence of an organic base. This procedure was then used for the production of a DNA array, in which synthesis was directed by the electrochemical removal of the DMT group during synthesis. The product array was found to have a detection sensitivity to as low as 0.5 pM DNA in a complex background sample.

Acids↗
PubMed2006

Building addressable libraries: site selective coumarin synthesis and the "real-time" signaling of antibody-coumarin binding.

[reaction: see text] The feasibility of using active semiconductor chips containing addressable arrays of microelectrodes for the "real-time" monitoring of biologically relevant binding events has been demonstrated by detecting the binding of a coumarin substrate by an anticoumarin antibody. The coumarin substrate was synthesized proximal to predetermined electrodes on the chip with the use of a Pd(II) reagent that was itself generated by using the selected electrodes. Once the coumarin was synthesized, its binding to the anticoumarin antibody was detected by monitoring the current associated with a ferrocene-ferrocinium ion redox cycle that was established between the electrodes on the chip and a remote auxiliary electrode.

Antibodies↗
PubMed2006

Building addressable libraries: spatially isolated, chip-based reductive amination reactions.

A Pd(II) reagent has been generated at preselected sites on an electrochemically addressable chip and used to effect the oxidation of the neighboring alcohols on the polymer coating the chip's surface. The resulting carbonyls were then used to accomplish site-selective reductive amination reactions on the chips. The work demonstrates that the confinement strategy developed for spatially isolated Wacker oxidations to specific sites on the chips is general and can be used for other Pd(II)-based reactions.

Alcohols↗
PubMed2005

Building addressable libraries: the use of electrochemistry for spatially isolating a heck reaction on a chip.

Pd(0) was generated at preselected sites on an electrochemically addressable chip and then utilized to effect a Heck reaction. The Pd(0) was confined to the preselected electrodes with the use of allylmethyl carbonate. Unlike most mediated electrochemical reactions, the electrolysis in this case was not used to convert a stoichiometric process into a catalytic one by recycling the metal. Instead, the unique environment of the chip was used to interfere with a catalytic process to make it stoichiometric. This was done to gain spatial control over the reaction. The development of a strategy for conducting Pd(0)-catalyzed reactions on the chips should greatly expand the synthetic chemistry available for building chip-based libraries.

Combinatorial Chemistry Techniques↗
PubMed2004

Building addressable libraries: the use of electrochemistry for generating reactive Pd(II) reagents at preselected sites on a chip.

A Pd(II) reagent has been generated at preselected sites on an electrochemically addressable chip. The reagent was used to effect the Wacker oxidation of an olefin substrate bound to the chip near the electrode. The use of ethyl vinyl ether in the solution above the chip effectively kept the Pd(II) reagent generated at the preselected electrode from migrating to neighboring electrodes and initiating Wacker oxidations at unwanted sites on the chip.

2,4-Dinitrophenol↗