Stick, Switch, Click

See allHide authors and affiliations

Science  10 Feb 2006:
Vol. 311, Issue 5762, pp. 745
DOI: 10.1126/science.311.5762.745a

Microelectrode arrays can be useful in sensor devices, but the application of such arrays depends on being able to modify their surfaces in a controlled fashion. Devaraj et al. have adapted a “click” reaction—the high-yield coupling of an azide to an alkyne—so that microelectrodes that are only 10 μm apart can be derivatized sequentially using the same ligation chemistry.

Azide-terminated alkane thiols were selfassembled onto gold microelectrodes on a silicon substrate, and then placed in contact with an electrolyte solution containing a Cu(II) bis(bathophenanthroline)disulfonic acid complex and ethynylferrocene (the alkyne). Switching on a negative bias (0.3 V) at one microelectrode reduced the copper complexes in the immediate vicinity to the active Cu(I) state, which enabled them to catalyze the click reaction between the azide and the alkyne. Nearby, positively biased microelectrodes were not functionalized and remained available for subsequent priming and reaction with other alkynes. — PDS

J. Am. Chem. Soc. 10.1021/ja058380h (2006).

Navigate This Article