Protein Discrimination Using Fluorescent Gold Nanoparticles on Plasmonic Substrates

Abstract

Fluorescent gold nanoparticle (GNP) is an easily synthesized and biocompatible optical platform for sensing and imaging with tunable near-infrared (NIR) emission. However, the relatively low fluorescence (FL) quantum yield limits the further improvement of sensitivity and application. Here, we find that, on plasmonic substrates, the FL intensity of protein-directed synthesized GNPs can be enhanced significantly (~20-fold). Moreover, protein analytes can interact with GNPs and influence the enhanced fluorescence process so that we can obtain distinct FL image patterns. Then, using the array-based sensing strategy, protein discrimination can be achieved. In our present experiment, five GNPs were used as sensing elements and 10 kinds of proteins at three concentrations (0.2, 0.5, and 1 μM) were successfully identified. This array-based sensing strategy using enhanced-fluorescence from GNPs is highly sensitive and differentiable, expanding the application field of GNPs.

Pattern-based sensing of triple negative breast cancer cells with dual-ligand cofunctionalized gold nanoclusters

“…Analogous to our own noses, chemical nose sensors preclude the need of prior knowledge of the analytes and are instead “trained” to identify analytes [29, 30]. A wealth of applications of chemical nose sensors are demonstrated, including detection of metal ions [31], volatile organic compounds [32, 33], carbohydrates [34, 35], amino acids [36, 37], and proteins [38–45]. Recently, these strategies have been expanded to more complex systems, such as cell [46–55] and bacteria [56–61] sensing.…”

Fluorescent Gold Nanodots Based Sensor Array for Proteins Discrimination

“…Both CytC and Myo contain hemin moiety; thus, they may quench the fluorescence of all Au NDs, and hemin contained proteins can also induce the fluorescence quenching of protein stabilized Au NDs. 48 Besides CytC and Myo, trypsin (Try) can also quench the fluorescence of all Au NDs. Although Try has no strong absorption near the excitation or emission wavelength range of Au NDs, the metal center of Try may possibly be the reason for the induced fluorescence quenching.…”

High‐Level Incorporation of Silver in Gold Nanoclusters: Fluorescence Redshift upon Interaction with Hydrogen Peroxide and Fluorescence Enhancement with Herbicide

“…[15] With their ultrasmall size, strongf luorescence, and low toxicity,v ariousf luorescent noblem etal NCs have been exploited extensively in chemical detection involving analyte-induced fluorescenceq uenching. [16][17][18][19][20][21][22][23][24] Earlier successful examples were demonstrated to detect Hg 2 + and Cu 2 + through the aggregation of Au NCs inducedb ym etal ions, or the dissociation of Au NCs through ah igh-affinity metallophilic interaction with the surface Au + of Au NCs. [17][18][19][20] Noble metal NCs have also been applied in the chemical detection of inorganic anions (CN À ,N O 2 À ), [21] hydrogen peroxide( H 2 O 2 ), [22,23] and proteins.…”

“…[17][18][19][20] Noble metal NCs have also been applied in the chemical detection of inorganic anions (CN À ,N O 2 À ), [21] hydrogen peroxide( H 2 O 2 ), [22,23] and proteins. [24] However, until now,n oble metal NCs have not been used successfully to detect herbicides, which have becomeo ne of the major concerns in our daily life over the past decade owing to their contamination of drinking water and agricultural products. This is because noble metal NCs were not fluorescently responsive to most herbicides, and therefore, it is ag reat challenge to apply them for the sensitived etection of herbicides.…”