Highly luminescent AgInSe₂/ZnS core/shell quantum dots (AISe/ZnS QDs) have been synthesized via a facile low-temperature solution chemistry route. The as-prepared core/shell QDs have a narrow size distribution, and exhibit composition-tunable photoluminescence (PL) emission in the near-infrared (NIR) range from 700 to 820 nm with a maximum PL quantum yield (QY) of 40%. By using the poly(acrylic acid)–octylamine (PAA-based) amphiphilic polymer, these oil-soluble AISe/ZnS core/shell QDs could be effectively solubilized in water, while retaining their initial morphology, crystal structure and PL properties. Importantly, the results from animal and cell experiments confirm that these highly luminescent, broadly emissive AISe/ZnS QDs are new promising fluorescent probes for biomedical optical imaging (namely, in vivo animal and in vitro cell imaging), as an alternative for Cd-, Hg- and Pb-based QDs and organic dyes.

Exploring the synthesis and biomedical applications of biocompatible quantum dots (QDs) is currently one of the fastest growing fields of nanotechnology. Hence, in this work, we present a facile approach to produce water-soluble (cadmium-free) quaternary Zn–Ag–In–S (ZAIS) QDs. Their efficient photoluminescence (PL) emissions can be tuned widely in the range of 525–625 nm by controlling the size and composition of the QDs with the PL quantum yields (QYs) of 15–30%. These highly luminescent ZAIS QDs are less toxic due to the absence of highly toxic cadmium, and can be versatilely modified by a DHLA-PEG-based ligand. Importantly, after being modified by tumor cell-specific targeting ligands (e.g., folate and RGD peptide), the PEGylated quaternary QDs show potential applications in tumor cell imaging as a promising alternative for Cd-based QDs.

Natural plant compounds have long served as crucial sources of medicinal therapies, spanning millennia and underpinning the field of drug discovery and development. Their profound impact is rooted in their extensive diversity and broad spectrum of pharmacological activities. Inspired by the decoction methods of traditional Chinese medicine, we have delved into the co-assembly strategy of natural plant compounds. This strategy involves the coalescence of active components from various drugs into nanocomplexes via non-covalent interactions during the decoction process. Consequently, this approach enhances the biocompatibility, biodegradability, and pharmacological efficacy of natural plant small molecules while mitigating their toxicity. The co-assembly strategy capitalizes on the inherent advantages of natural plant compounds, thereby expediting drug discovery by repurposing existing drugs. This review outlines the evolution of co-assembly strategies involving natural plant compounds, provides illustrative examples of co-assembly, elucidates the mechanisms underlying assembly, and highlights the resultant advantages. By shedding light on the transition from single molecule to multi-component interactions, this review advances our understanding, facilitating further research and the practical application of co-assembly strategies for natural plant compounds.