Since the discovery of metal nanoparticles (NPs) in the 1960s, unknown toxicity, cost and the ethical hurdles of research in humans have hindered the translation of these NPs to clinical use. In this work, we demonstrate that Pt NPs with protein coronas are generated in vivo in human blood when a patient is treated with cisplatin. These self-assembled Pt NPs form rapidly, accumulate in tumors, and remain in the body for an extended period of time. Additionally, the Pt NPs are safe for use in humans and can act as anti-cancer agents to inhibit chemotherapy-resistant tumor growth by consuming intracellular glutathione and activating apoptosis. The tumor inhibitory activity is greatly amplified when the Pt NPs are loaded in vitro with the chemotherapeutic drug, daunorubicin, and the formulation is effective even in daunorubicin-resistant models. These in vivo-generated metal NPs represent a biocompatible drug delivery platform for chemotherapy resistant tumor treatment.

Because they generate excellent images, nanoparticles (NPs), especially biosynthesized NPs, provide a new solution for tumor imaging. In this research, we unveil a novel type of biosynthesized NPs featuring multicolor fluorescence. These NPs exhibit little cytotoxicity to cells. The explored NPs, designated Zn-ZFP-GST NPs (Zinc NPs in abbreviation), are generated from leukemia cells treated with a Zn²⁺ solution, while zinc-finger protein and glutathione S-transferase (GST) were also identified in the Zinc NPs. Under near-UV illumination, the Zinc NPs simultaneously emit green, yellow, and red fluorescence. In addition, the intensity of the fluorescence increases with the existence of sulfides. Besides, the NPs are encapsulated by microvesicles (MVs) shed from the plasma membrane. As observed in whole-body research of nude mice, the NP-MVs migrate via blood circulation and are distinguished by their fluorescent signals. Furthermore, the folic acid (FA) & AVR2 (human VEGF antibody)-coated NP-MVs are exploited to target the tumor location, and the feasibility of this approach has been confirmed empirically. The Zinc NPs shed light on an alternative solution to tumor detection.