Controlling the Interaction between Fluorescent Gold Nanoclusters and Biointerfaces for Rapid Discrimination of Fungal Pathogens

Abstract

Nondestructive detection and discrimination of fungal pathogens is essential for rapid and precise treatment, which further effectively prevents antifungal resistance from overused drugs. In this work, fluorescent gold nanoclusters served as the basis for discriminating Candida species. Varied on surface ligands, these gold nanoclusters demonstrated different optical properties as a result of the perturbation effects of ligands. The biointerface interaction between the surface ligands of gold nanoclusters and the cell walls of Candida species can be constructed, and their restriction on ligands perturbation effect produced enhanced fluorescence signals. Owing to the variation of the cell wall composition, cells of different Candida species demonstrated different degrees of association with the gold nanoclusters, leading to discriminable amounts of fluorescence enhancements. The reverse signal response from these gold nanoclusters gives rise to a synergistic and effective assay that allows identification of Candida species.

Controllable Gold Nanocluster–Emulsion Interface for Direct Cell Penetration and Photothermal Killing

“…In view of its conformational arrangement in Au@DVP(L), DVP probably covered the surface of Au NCs and attenuated thermal dissipation from the Au NC core. However, the anchoring of the DVP moiety in the interior of Au@DVP(L)‐P droplets reduced DVP‐induced perturbation [ 42 ] and facilitated thermal dissipation (Figure 3e). This anchoring effect possibly became less pronounced with increasing DVP content.…”

The roles of templates consisting of amino acids in the synthesis and application of gold nanoclusters

“…The fluorescence signal of AuNCs can discriminate different Candida species. 129 When AuNCs were synthesized on the surface of living Lactobacillus rhamnosus , larger aggregates of AuNCs appeared in the latter generation due to wall remodeling in transformation of the AuNCs. 130 Based on their high biocompatibility, polyvalent effect, and ease of modification, 131 AuNCs with well-defined ligands could be constructed as antimicrobial agents toward both Gram-negative 132,133 and Gram-positive bacteria, 134 using quaternary ammonium compounds, antibiotics, amino acids, and antibacterial peptides.…”

Photofunctional Gold Nanocluster Composites for Bioapplications

“…Due to the different ratios of hydrophobic protein to oligosaccharide on the cell wall of Candida species, isothermal titration microcalorimetry (ITC) measurements revealed different degrees of binding for two AuNCs. This led to distinguishable fluorescence enhancements, providing an efficient method for specific biorecognition . Additionally, positively charged arginine-coated GSH-AuNCs can bind with negatively charged tumor cell membranes through electrostatic interactions, facilitating the internalization of AuNCs by tumor cells .…”