Nanoparticle (NP) assemblies are among the foremost achievements of nanoscience and nanotechnology because their interparticle interactions overcome the weaknesses displayed by individual NPs. However, previous studies have considered NP assemblies as inanimate, which had led to their dynamic properties being overlooked. Animate properties, i.e., those mimicking biological properties, endow NP ensembles with unique and unexpected functionalities for practical applications. In this critical review, we highlight recent advances in our understanding of the properties of NP assemblies, particularly their animate properties. Key examples are used to illustrate critical concepts, and special emphasis is placed on animate property-dependent applications. Last, we discuss the barriers to further advances in this field.

Herein, a series of PdAu/C alloyed catalysts were synthesized via a modified coprecipitation–reduction method by using carbon powder as a support, and their activities towards formic acid decomposition (FAD) at room temperature (30 °C) were evaluated.

The interfacial mass transfer rate of a target has a significant impact on the sensing performance. The surface reaction forms a concentration gradient perpendicular to the surface, wherein a slow mass transfer process decreases the interfacial reaction rate. In this work, we self-assembled gold nanoparticles (AuNPs) in the gap of a SiO2 opal array to form a AuNP-bridge array. The diffusion paths of vertical permeability and a microvortex effect provided by the AuNP-bridge array synergistically improved the target mass transfer efficiency. As a proof of concept, we used DNA hybridization efficiency as a research model, and the surface-enhanced Raman spectroscopy (SERS) signal acted as a readout index. The experimental verification and theoretical simulation show that the AuNP-bridge array exhibited rapid mass transfer and high sensitivity. The DNA hybridization efficiency of the AuNP-bridge array was 15-fold higher than that of the AuNP-planar array. We believe that AuNP-bridge arrays can be potentially applied for screening drug candidates, genetic variations, and disease biomarkers.