Simple and rapid colorimetric detection of low-weight molecules using aptazymes in combination with noncrosslinking gold nanoparticle aggregation.

We developed a method for simply and rapidly detecting cofactors of aptazymes with high sensitivity using a unique noncrosslinking gold nanoparticle aggregation. Applying this method to a theophylline dependent aptazyme, 100 microM, 10 microM, and 1 microM theophylline were detected easily by the naked eye within 10 min, 20 min, and 65 min, respectively. This method is applicable to other cleavage-aptazymes without altering the probe-DNA sequence.