DNA-Stabilized Silver Nanoclusters as Specific, Ratiometric Fluorescent Dopamine Sensors

Abstract

Neurotransmitters are small molecules that orchestrate complex patterns of brain activity. Unfortunately, there exist few sensors capable of directly detecting individual neurotransmitters. Those sensors that do exist are either unspecific or fail to capture the temporal or spatial dynamics of neurotransmitter release. DNA-stabilized silver nanoclusters (DNA-AgNCs) are a new class of biocompatible, fluorescent nanostructures that have recently been shown to offer promise as biosensors. In this work, we identify two different DNA sequences that form dopamine-sensitive nanoclusters. We demonstrate that each sequence supports two distinct DNA-AgNCs capable of providing specific, ratiometric fluorescent sensing of dopamine concentration in vitro. DNA-Ag nanoclusters therefore offer a novel, low-cost approach to quantification of dopamine, creating the potential for real-time monitoring in vivo.

Structure and luminescence of DNA-templated silver clusters

“…Many chemical and biomolecular sensing schemes employing Ag N -DNAs have been developed, such as NanoCluster Beacons, 32,39 ratiometric sensors, [234][235][236] and microRNA sensors 14,119 (more complete list in a past review 74 ). Designing these sensors is extremely challenging, and designs may not generalize because silver clusters are not conned only to the expected regions of a probe.…”

Massively Parallel Selection of NanoCluster Beacons

“…We also found brighter NCBs could be achieved with fewer numbers of guanine bases in the activators. Our chip screening platform can facilitate the development of new chemical sensors based on DNA-templated AgNCs 50 or be used to study other metal nanoclusters templated in DNA [51][52][53] . To our knowledge, this article is the first report that NGS chips are repurposed for high-throughput screening of fluorescent nanomaterials.…”

Nanotechnology‐Based Strategies for Early Diagnosis of Central Nervous System Disorders

“…Thus, being a potential biomarker, DA could play an essential role in the pathogenesis and diagnosis of PD. [ 202 ] So far, numerous DA biomarker detection approaches have been proposed, such as fluorescence, [ 203 ] naked‐eyed and electrochemical assays, [ 204 ] SERS, [ 205 ] chemiluminescence, [ 206 ] mass spectrometry techniques, [ 207 ] and biosensor. [ 208 ] Nanotechnology‐based biosensing for PD measured the DA level in biological fluids with extreme sensitivity due to the low abundance of DA in sample matrices.…”