A simple and sensitive aptasensor for colorimetric detection of adenosine triphosphate based on unmodified gold nanoparticles

Publication date: 1 June 2017
Source:Talanta, Volume 168
Author(s): Yu Mao, Tingting Fan, Rachel Gysbers, Yin Tan, Feng Liu, Shuo Lin, Yuyang Jiang
A simple and sensitive colorimetric aptasensor for rapid and facile detection of adenosine triphosphate (ATP) has been demonstrated here based on aptamer-based hairpin probes and unmodified gold nanoparticles (AuNPs). The hairpin probe is constructed by adding another five nucleotides to the 5′-end of an anti-ATP aptamer which can hybridize to nucleotides at the 3′-end of the aptamer, forming a hairpin-shaped structure. In the absence of ATP, the hairpin probes are rigid, and the AuNPs are susceptible to salt-induced aggregation. Conversely, upon binding with target ATP, the hairpin probes undergo conformational changes, forming aptamer-ATP complexes and exposing flexible ends which coat the surface of AuNPs to inhibit their aggregation in the high salt solution. Subsequently, a blue-to-red color change can be recognized by the naked eye. The aptasensor achieved selective responses toward ATP with a detection limit of 0.1μM, and exhibited high-quality detection performance in biological samples. In addition, this detection method is simple, rapid and cost-effective, holding great potential for further applications in point-of-care research.

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