Recent advances in templated synthesis of metal nanoclusters and their applications in biosensing, bioimaging and theranostics

Modular engineering of gold-silver nanocluster supermolecular structure endow strong electrochemiluminescence for ultrasensitive bioanalysis

Here, the gold-silver nanocluster supramolecular network (AuAg NCs) is synthesized by the assembly of Au nanoclusters (Au NCs) and Ag NCs via host-guest complexation between 6-aza-2-thiothymine as the stabilizer of Au NCs and L-arginine as the stabilizer of Ag NCs in solution, whose electrochemiluminescence (ECL) emission is not only exceptionally stronger than that of discrete monometallic NCs, but also more significant than that of agminated monometallic NCs. The dramatically enhanced ECL emission of self-assembled AuAg NCs originates from the synergistic effect of aggregation-induced enhancement and silver effect in gold catalysis. As a proof of concept, the self-assembled AuAg NCs is successfully applied in the ultrasensitive detection of breast cancer biomarker microRNAs-21 (miR-21), which guides a new pathway for creating high-quality nano-optical elements in chemical sensors, biological imaging, and lightemitting devices.

High Stability Au NPs: From Design to Application in Nanomedicine

In recent years, Au-based nanomaterials are widely used in nanomedicine and biosensors due to their excellent physical and chemical properties. However, these applications require Au NPs to have excellent stability in different environments, such as extreme pH, high temperature, high concentration ions, and various biomatrix. To meet the requirement of multiple applications, many synthetic substances and natural products are used to prepare highly stable Au NPs. Because of this, we aim at offering an update comprehensive summary of preparation high stability Au NPs. In addition, we discuss its application in nanomedicine. The contents of this review are based on a balanced combination of our studies and selected research studies done by worldwide academic groups. First, we address some critical methods for preparing highly stable Au NPs using polymers, including heterocyclic substances, polyethylene glycols, amines, and thiol, then pay attention to natural product progress Au NPs. Then, we sum up the stability of various Au NPs in different stored times, ions solution, pH, temperature, and biomatrix. Finally, the application of Au NPs in nanomedicine, such as drug delivery, bioimaging, photothermal therapy (PTT), clinical diagnosis, nanozyme, and radiotherapy (RT), was addressed concentratedly.