A cost-effective approach for non-persistent gold nano-architectures production

The effective exploitation of the intriguing theranostic features of noble metal nanoparticles for therapeutic applications is far from being a routine practice due to the persistence issue. In this regard, passion fruit-like nano-architectures (NAs), biodegradable and excretable all-in-one, nature-inspired platforms which jointly combine these characteristics with the appealing optical behaviors of noble metal nanoparticles, can offer a new alternative for theranostic applications. Besides the need for efficacious and innovative systems, the reliable and cost-effective production of nanomaterials is a pivotal subject for their translation to the clinical setting. Here, we demonstrate the production of a new cheaper class of degradable, ultrasmall-in-nano-architectures (dragon fruit NAs, dNAs) using polyethyleneimine (PEI) as a cationic polymer without affecting either their compositions or their physiological behaviors, compared to the previous NAs. In particular, the standardized protocol characterized in this work ensures the preparation of high gold-loading capacity nanoparticles, a peculiar characteristic that, synergically with the interesting properties of PEI, may unlock new possible applications previously precluded to the first version of NAs while reducing the hand-made production cost by three orders of magnitude.