Simple and rapid colorimetric detection of cofactors of aptazymes using noncrosslinking gold nanoparticle aggregation

We developed a method for simply and rapidly detecting cofactors of aptazymes with high sensitivity using unique noncrosslinking gold nanoparticle aggregation. Applying this method to a theophylline-dependent aptazyme, 100 mu M, 10 mu M, and 1 mu M theophylline were detected easily by the naked eye within 10 min, 20 min, and 65 min, respectively. This method is also applicable to other cleavase-aptazymes without altering the probe-DNA sequence on the gold nanoparticle. (C) 2008 Elsevier Ltd. All rights reserved.