Persistent luminescence nanoparticles with high intensity for colorectal cancer surgery navigation and precision resection.

Surgical resection remains the main treatment for malignant tumors. Image-guided surgery aims to remove tumor tissue completely while preserving normal tissue, thereby reducing tumor recurrence rates and injury. However, challenges like tissue autofluorescence, limited probe penetration and low contrast restrict its use. Near-infrared (NIR) persistent luminescent nanoparticles (PLNPs) provide a solution by emitting persistent luminescence (PersL) even after excitation ceases, thus circumventing autofluorescence and enabling deep tumor imaging. In this study, we prepared nano-sized (140 nm hydrodynamic size) Cr3+ doped zinc gallogermanate (ZGC) using a removable template method and modified it with folate acid to obtain ZGC-FA, which exhibits NIR (695 nm) PersL with a signal-to-noise ratio of 23.9 in vivo. We utilized a colon cancer model that selectively expressed luciferase for the first time to validate the guiding efficacy of ZGC-FA in precision surgical resection. Post-intraperitoneal injection at 50 minutes, the PersL closely matched the tumor boundaries, achieving an overlap rate of approximately 98%. Complete tumor resection was achieved under PersL guidance, with only 2.3% of healthy tissue removed. This research underscores the potential of ZGC-FA in the field of surgical oncology. The precision of the ZGC-FA guided surgical approach holds promise to enhance surgical outcomes and facilitate postoperative recovery in patients.

Enhancing Persistent Luminescence through Synergy between Optimal Electron Traps and Dye Sensitization.

Due to their unique afterglow ability, long-wavelength-light rechargeable persistent luminescence (PersL) nanoparticles (PLNPs) have been emerging as an important category of imaging probes. Among them, ZnGa2O4:0.6% Cr3+ (ZGC) PLNPs have gained widespread recognition due to the ease of synthesis and uniform morphology. Unfortunately, the limited absorption arising from the low molar extinction coefficient of Cr3+ results in relatively low afterglow intensity and rapid decay after long-wavelength LED light irradiation. Herein, we discovered a strategy that boosting dye-sensitization performance was able to effectively amplify the PersL signal under white LED light. Specifically, Dil served as a highly efficient sensitizer for Cr3+, promoting the absorption of the excitation light. By adjusting the Pr dopant concentrations, ZGCP0.5 PLNPs with optimal trap densities were obtained, which showed the highest PersL intensity and dye-sensitized performance. Strikingly, ZGCP0.5-Dil PLNPs exhibited a 24.3-fold enhancement in intensity and a 2-fold prolongation of decay time over bare ZGC PLNPs through the synergy effect of optimal electron traps and dye sensitization. Photostable ZGCP0.5-Dil PLNPs enabled imaging of the HepG2 tumor and effectively guided tumor surgical resection verified by the H&E staining analysis. This strategy could be a significant reference in other dye-sensitization PLNPs to enhance longer-wavelength rechargeable PersL.

pH-Responsive Plasmon-Enhanced Persistent Luminescent ZnGa2O4:Cr3+ Nanopomegranate for Tumor Imaging.

Noble metal compositing is a promising method to enhance radiance intensity of persistent luminescent (PersL) nanoparticles (NPs) via surface plasmon resonance (SPR) for better tumor imaging, but it rarely unites with the pH-response strategy due to the challenge of realizing rigorous pH-responsive spatial distance control as a "button switch" of SPR. Here, ZnGa2O4:Cr3+ (ZGC) NPs as "pomegranate seeds" are cladded with sodium alginate to form nanoclusters (ZGC-SA), subsequently coated with carboxyl-rich polymers to acquire "pomegranate rind" (ZSPB) and finally decorated with 10 nm gold NPs (AuNPs) on the surface to obtain nanopomegranate structure (ZSPB@AuNPs). Though without deliberate distance control, there are plenty of "seeds" inside ZSPB@AuNPs fortunately at appropriate positions, which could be plasmon-enhanced by AuNPs. Furthermore, triggered by carboxyl protonation in subacid tumor, ZSPB@AuNPs aggregate and subsequently facilitate such plasmon enhancement effect, resulting in 4.4-fold PersL promotion at pH 5.5 (tumor microenvironment, TME) over pH 7.4 and in a maximum "tumor to normal tissue ratio" of PersL imaging signals of 125.9. Under surgical navigation of ZSPB@AuNPs, intramuscular tumors of mice could be resected without residue signals left. This nanopomegranate achieves TME pH-responsive plasmon-enhanced PersL for the first time and broadens the way for designing plasmon-enhanced PersL nanosystems.

Preparation of Bacillus-mimic liposomes destroying TAMs for the treatment of cancer.

The enrichment rate of drugs in tumors seriously affects the effect of tumor treatment. Tumor-associated macrophages (TAMs) could penetrate deeply into the tumor and accumulate in hypoxic areas. Therefore, using TAMs to deliver drugs can effectively increase the enrichment rate. However, as immune cell, macrophages will clear the internal drugs and their antitumor activity. Mycobacterium tuberculosis (M. tuberculosis) can inhibit the decomposition ability of TAMs and stay stable in macrophages. Herein, we prepared a Bacillus-mimic liposome by embedding the fragments of M. tuberculosis into the liposome. In vitro experiments showed that it can stay stable in TAMs for at least 29 h without decomposing. Then, TAMs would burst as they gobble up materials and cannot digest them. Thus, the prepared liposome could "domesticate" TAMs and kill macrophages after they are used up, further destroy the tumor microenvironment, and finally kill the tumor. Cytotoxicity experiments confirmed that it has a certain killing effect on macrophages, tumor cells, and normal cells. In vivo tumor suppression experiments confirmed that it has the effect of inhibiting tumor growth.

A novel removable template method for the preparation of persistent luminescence nanoparticles with biocompatible size and high intensity.

NIR persistent luminescence nanoparticles (PLNPs) are appealing for bio-imaging because of the properties of extremely low autofluorescence interference and deep tissue penetrating ability. However, current preparation methods can hardly simultaneously endow PLNPs with nano-scale size, long persistent luminescence (PersL) life, and high luminescence intensity, which can hardly meet the requirements of bio-imaging. Herein, we report a new synthetic route to nano-sized chromium-doped zinc gallate (ZGC) via a removable MOF template, i.e., one-pot hydrothermal synthesis of an intermediate followed by its calcination at 1100 °C in air. By exploiting the regulatory effect of the intermediate on Zn and Ga, the depth of traps in 170 nm-sized ZGC nanoparticles was enhanced to above 0.8 eV, and the PersL duration to more than 24 h, with an average lifetime of up to 216 s. An in vivo experiment shows that tumors can be accurately delineated for more than 3 hours. This strategy largely resolves the conflict between the particle size and PersL properties of PLNPs, and expands the application of PLNPs in bio-imaging.

Tumor acid microenvironment-activated self-targeting & splitting gold nanoassembly for tumor chemo-radiotherapy.

Low accumulation and penetration of nanomedicines in tumor severely reduce therapeutic efficacy. Herein, a pH-responsive gold nanoassembly is designed to overcome these problems. Polyethylene glycol linked raltitrexed (RTX, target ligand and chemotherapy drug) and two tertiary amine molecules (1-(2-aminoethyl) pyrrolidine and N, N-dibutylethylenediamine) are modified on the surface of the 6-nm gold nanoparticles by lipoic acid to form gold nanoassembly defined as Au-NNP(RTX). The Au-NNP (RTX) nanoassembly could remain at about 160 nm at the blood circulation (pH 7.4), while split into 6-nm gold nanoparticles due to tertiary amine protonation at tumor extracellular pH (pH 6.8). This pH-responsive disassembly behavior endows Au-NNP(RTX) better tumor tissue permeability through the better diffusion brought by the size reduction. Meanwhile, after disassembly, more RTXs on the surface of gold nanoparticles are exposed from the shielded state of assembly along with 2.25-fold augment of cellular uptake capability. Most importantly, the results show that Au-NNP(RTX) possesses of high tumor accumulation and effective tumor penetration, thereby enhancing the tumor chemo-radiotherapy efficiency.

Epitaxial Nickel Ferrocyanide Stabilizes Jahn-Teller Distortions of Manganese Ferrocyanide for Sodium-Ion Batteries.

Manganese-based Prussian Blue, Na2-δ Mn[Fe(CN)6 ] (MnPB), is a good candidate for sodium-ion battery cathode materials due to its high capacity. However, it suffers from severe capacity decay during battery cycling due to the destabilizing Jahn-Teller distortions it undergoes as Mn2+ is oxidized to Mn3+ . Herein, the structure is stabilized by a thin epitaxial surface layer of nickel-based Prussian Blue (Na2-δ Ni[Fe(CN)6 ]). The one-pot synthesis relies on a chelating agent with an unequal affinity for Mn2+ and Ni2+ ions, which prevents Ni2+ from reacting until the Mn2+ is consumed. This is a new and simpler synthesis of core-shell materials, which usually needs several steps. The material has an electrochemical capacity of 93 mA h g-1 , of which it retains 96 % after 500 charge-discharge cycles (vs. 37 % for MnPB). Its rate capability is also remarkable: at 4 A g-1 (ca. 55 C) it can reversibly store 70 mA h g-1 , which is also reflected in its diffusion coefficient of ca. 10-8  cm2 s-1 . The epitaxial outer layer appears to exert an anisotropic strain on the inner layer, preventing the Jahn-Teller distortions it normally undergoes during de-sodiation.

Nickel sulfide nanocrystals on nitrogen-doped porous carbon nanotubes with high-efficiency electrocatalysis for room-temperature sodium-sulfur batteries.

Polysulfide dissolution and slow electrochemical kinetics of conversion reactions lead to low utilization of sulfur cathodes that inhibits further development of room-temperature sodium-sulfur batteries. Here we report a multifunctional sulfur host, NiS2 nanocrystals implanted in nitrogen-doped porous carbon nanotubes, which is rationally designed to achieve high polysulfide immobilization and conversion. Attributable to the synergetic effect of physical confinement and chemical bonding, the high electronic conductivity of the matrix, closed porous structure, and polarized additives of the multifunctional sulfur host effectively immobilize polysulfides. Significantly, the electrocatalytic behaviors of the Lewis base matrix and the NiS2 component are clearly evidenced by operando synchrotron X-ray diffraction and density functional theory with strong adsorption of polysulfides and high conversion of soluble polysulfides into insoluble Na2S2/Na2S. Thus, the as-obtained sulfur cathodes exhibit excellent performance in room-temperature Na/S batteries.