Gram-scale synthesis of coordination polymer nanodots with renal clearance properties for cancer theranostic applications

Tailored ultra-small Prussian blue-based nanoparticles for MRI imaging and combined photothermal/photoacoustic theranostics

Ultrasmall sub-10 nm nanoparticles of Prussian blue analogues incorporating GdIII ions at their periphery revealed longitudinal relaxivities above 40 mM-1 s-1 per GdIII regardless of the nature of the core and the polymer coating. Large T1-weighted contrast enhancements were achieved in addition to a highly efficient photothermal effect and in vivo photoacoustic imaging in tumors.

Precision-Guided Missile-Like DNA Nanostructure Containing Warhead and Guidance Control for Aptamer-Based Targeted Drug Delivery into Cancer Cells in Vitro and in Vivo

It is crucial to deliver anticancer drugs to target cells with high precision and efficiency. While nanomaterials have been shown to enhance the delivery efficiency once they reach the target, it remains challenging for precise drug delivery to overcome the nonspecific adsorption and off-target effect. To meet this challenge, we report herein the design of a novel DNA nanostructure to act as a DNA nanoscale precision-guided missile (D-PGM) for highly efficient loading and precise delivery of chemotherapeutic agents to specific target cells. The D-PGM consists of two parts: a warhead (WH) and a guidance/control (GC). The WH is a rod-like DNA nanostructure as a drug carrier, whose trunk is a three-dimensionally self-assembled DNA nanoscale architecture from the programmed hybridization among two palindromic DNA sequences in the x-y dimension and two common DNA oligonucleotides in the z direction, making the WH possess a high payload capacity of drugs. The GC is an aptamer-based logic gate assembled in a highly organized fashion capable of performing cell-subtype-specific recognition via the sequential disassembly, mediated by cell-anchored aptamers. Because of the cooperative effects between the WH and the GC, the GC logic gates operate like the guidance and control system in a precision-guided missile to steer the doxorubicin (DOX)-loaded DNA WH toward target cancer cells, leading to selective and enhanced therapeutic efficacy. Moreover, fluorophores attached to different locations of D-PGM and DOX fluorescence dequenching upon release enable intracellular tracing of the DNA nanostructures and drugs. The results demonstrate that by mimicking the functionalities of a military precision-guided missile to design the sequential disassembly of the GC system in multistimuli-responsive fashion, our intrinsically biocompatible and degradable D-PGM can accurately identify target cancer cells in complex biological milieu and achieve active targeted drug delivery. The success of this strategy paves the way for specific cell identity and targeted cancer therapy.

Combinatorial discovery of Mo-based polyoxometalate clusters for tumor photothermal therapy and normal cell protection

Molybdenum (Mo)-based polyoxometalate clusters can kill cancer cells selectively by PTT assay and protect the normal cells by scavenging ROS effectively.

Activatable Core-Shell Metallofullerene: An Efficient Nanoplatform for Bimodal Sensing of Glutathione

Metallofullerenes have attracted considerable attention as potential novel noninvasive high-relaxivity magnetic resonance contrast agents. However, the applications of metallofullerenes as stimuli-responsive biosensors to monitor biological processes are still scarce. Herein, manganese-fullerenes core-shell nanocomposites are prepared via a facile one-pot approach to achieve GSH-activatable magnetic resonance/fluorescence bimodal imaging functions. The nanocomposites initially have a FRET-induced quenched fluorescence, and water-resisting stimulated low T₁-MRI contrast. Upon exposure to GSH, collapse of the outer MnO₂ shell led to reconstruction of the nanoprobes and subsequently resulted in multicolor fluorescence recovery and longitudinal (T₁) relaxivity enhancement (r₁ value up to 29.8 mM^-1 s^-1 at 0.5 T based on Mn ion). Our work demonstrates feasibility of using fullerenes to fabricate activatable probes for molecular imaging of GSH, which may promote the development of new fullerene-based stimuli-responsive multimodal probes for the detection and regulation of particular biological processes in vivo.

Porous Inorganic and Hybrid Systems for Drug Delivery: Future Promise in Combatting Drug Resistance and Translation to Botanical Applications

BACKGROUND

Porous micro- and nanoparticles have the capacity to encapsulate a large quantity of therapeutics, making them promising delivery vehicles for a variety of applications. This review aims to highlight the latest development of inorganic and hybrid (inorganic/ organic) particles for drug delivery with an additional emphasis on combatting drug resistant cancer. We go one step further and discuss delivery applications beyond medicinal delivery, as there is generally a translation from medicinal delivery to botanic delivery after a short lag time.

METHODS

We undertook a search of relevant peer-reviewed publications. The quality of the relevant papers was appraised using standard tools. The characteristics of the papers are described herein, and the relevant material and therapeutic properties are discussed.

RESULTS

We discuss 4 classes of porous particles in terms of drug delivery and theranostics. We specifically focus on silica, calcium carbonate, metal-phenolic network, and metalorganic framework particles. Other relevant biomedically relevant applications are discussed and we highlight outstanding therapeutic results in the relevant literature.

CONCLUSION

The findings of this review confirm the importance of studying and utilizing porous particles for therapeutic delivery. Moreover, we show that the properties of porous particles that make them promising for medicinal drug delivery also make them promising candidates for agro-industrial applications.

Hypoxia-augmented and photothermally-enhanced ferroptotic therapy with high specificity and efficiency

The rigorous reaction conditions (sufficient H₂O₂ and a low pH value) of an efficient Fenton reaction limit its further biomedical translation. Therefore, it is urgent to improve the efficacy of the Fenton reaction at the tumor site for efficient ferroptotic therapy. Herein, a hypoxia-responsive-Azo-BSA functionalized biomimetic nanoreactor (Fe(iii)-GA/GOx@ZIF-Azo), encapsulating ultrasmall ferric-gallic acid coordination polymer nanoparticles (Fe(iii)-GA) and glucose oxidase (GOx) into a zeolitic imidazolate framework (ZIF), was constructed for tumor ablation through an intensive Fenton reaction accelerated by not only sustained Fe²⁺ and H₂O₂ supply but also low pH and photothermal stimulation. Moreover, Azo achieved charge reversal in a hypoxia microenvironment caused by the sustained oxygen consumption by GOx, which resulted in selective and enhanced tumor accumulation based on the hypoxia-activated positive feedback cellular uptake. This rationally designed biomimetic nanoreactor might lay a foundation for the clinical translation of ferroptotic therapy.

Optically Active Nanomaterials for Bioimaging and Targeted Therapy

Non-invasive tracking for monitoring the selective delivery and transplantation of biotargeted agents in vivo has been employed as one of the most effective tools in the field of nanomedicine. Different nanoprobes have been developed and applied to bioimaging tissues and the treatment of diseases ranging from inflammatory and cardiovascular diseases to cancer. Herein, we will review the recent advances in the development of optics-responsive nanomaterials, including organic and inorganic nanoparticles, for multimodal bioimaging and targeted therapy. The main focus is placed on nanoprobe fabrication, mechanistic illustrations, and diagnostic, or therapeutical applications. These nanomedicine strategies have promoted a better understanding of the biological events underlying diverse disease etiologies, thereby facilitating diagnosis, illness evaluation, therapeutic effect, and drug discovery.

Renal Clearable Ru-based Coordination Polymer Nanodots for Photoacoustic Imaging Guided Cancer Therapy

Rationale: Despite the promises of applying theranostic nanoagents for imaging-guided cancer therapy, the chronic retention of these nanoagents may cause safety concerns that hinder their future clinical applications. The metabolizable nanoagents with rapid renal excretion to avoid long-term toxicity is a possible solution for this issue. Method: Herein, we synthesize ultra-small metal-organic coordination polymer nanodots based on ruthenium ion (Ru3+) / phenanthroline (Phen) (Ru-Phen CPNs) with superior near-infrared (NIR) absorption. The size, photothermal conversion, cytotoxicity, photoacoustic imaging, in vivo & in vitro cancer treatment efficiency and biosafety are tested. Results: The size of the ultra-small Ru-Phen CPNs is 6.5 nm. The photothermal conversion efficiency is measured to be ~ 60.69 %, much higher than that of previously reported photothermal agents. The Ru-Phen CPNs could be employed for photoacoustic (PA, 808 nm) imaging-guided photothermal therapy (PTT, 808 nm, 0.5 W/cm2) with great performance. Notably, the intrinsic PA signals (808 nm) of Ru-Phen CPNs are observed in kidneys of treated mice, illustrating efficient renal clearance of those ultra-small CPNs. Moreover, the clearance of CPNs is further confirmed by detecting Ru levels in urine and feces. Conclusion: Our work presents a new type of ultra-small Ru-based CPNs with a record high photothermal conversion efficiency, efficient tumor retention after systemic administration, and rapid renal excretion to avoid long-term toxicity, promising for imaging-guided photothermal therapy.

Fe-doped copper sulfide nanoparticles for in vivo magnetic resonance imaging and simultaneous photothermal therapy

Multifunctional theranostic agents are widely applied in cancer diagnosis and treatment. These agents can significantly improve therapeutic outcomes and reduce adverse effects in current cancer therapy. Here, we have designed and synthesized iron-doped copper sulfide nanoparticles with polyvinylpyrollidone (FCS@PVP NPs) for magnetic resonance imaging (MRI) guided photothermal therapy. The biocompatible FCS@PVP NPs with strong near-infrared absorption could be used as the photothermal agent and the magnetic characteristic of Fe³⁺ ions could be applied to T ₁-weighted magnetic resonance imaging (MRI). The T ₁-weighted MRI, high photothermal performance, and the biodistribution of FCS@PVP NPs were investigated in mice after intravenous administration. The data showed that there was a high accumulation of FCS@PVP NPs in the tumor sites because of the enhanced permeability and retention (EPR) effect. This result also indicated that the tumors in tumor-bearing mice were effectively suppressed after FCS@PVP NPs treatment under 808 nm laser irradiation. More importantly, FCS@PVP NPs show low cytotoxicity and few side effects because of the quick and safe elimination through the hepatobiliary/fecal route. This work provided a foundation for the clinical application of FCS@PVP NPs as a promising multifunctional theranostic agent for the MRI guided photothermal therapy of cancer.

Exceedingly Small Gadolinium Oxide Nanoparticles with Remarkable Relaxivities for Magnetic Resonance Imaging of Tumors

Gd chelates have occupied most of the market of magnetic resonance imaging (MRI) contrast agents for decades. However, there have been some problems (nephrotoxicity, non-specificity, and low r₁ ) that limit their applications. Herein, a wet-chemical method is proposed for facile synthesis of poly(acrylic acid) (PAA) stabilized exceedingly small gadolinium oxide nanoparticles (ES-GON-PAA) with an excellent water dispersibility and a size smaller than 2.0 nm, which is a powerful T₁ -weighted MRI contrast agent for diagnosis of diseases due to its remarkable relaxivities (r₁ = 70.2 ± 1.8 mM^-1 s^-1 , and r₂ /r₁ = 1.02 ± 0.03, at 1.5 T). The r₁ is much higher and the r₂ /r₁ is lower than that of the commercial Gd chelates and reported gadolinium oxide nanoparticles (GONs). Further ES-GON-PAA is developed with conjugation of RGD2 (RGD dimer) (i.e., ES-GON-PAA@RGD2) for T₁ -weighted MRI of tumors that overexpress RGD receptors (i.e., integrin α_v β₃ ). The maximum signal enhancement (ΔSNR) for T₁ -weighted MRI of tumors reaches up to 372 ± 56% at 2 h post-injection of ES-GON-PAA@RGD2, which is much higher than commercial Gd-chelates (<80%). Due to the high biocompatibility and high tumor accumulation, ES-GON-PAA@RGD2 with remarkable relaxivities is a promising and powerful T₁ -weighted MRI contrast agent.

A pH-sensitive coordination polymer network-based nanoplatform for magnetic resonance imaging-guided cancer chemo-photothermal synergistic therapy

Developing various kinds of nanoplatforms with integrated diagnostic and therapeutic functions would be significant for imaging-guided precision treatment of cancer. However, it is still a challenge to organically integrate therapeutic and imaging components into a single nano-system rather than simply mixing. Herein, an iron-gallic acid network-based nanoparticle (Fe-GA@PEG-PLGA) was designed for magnetic resonance imaging (MRI)-guided chemo-photothermal synergistic therapy of tumors. The tumor spatial location and size information can be accurately achieved due to T₁ MRI based on Fe³⁺ coordination with GA in Fe-GA network. Furthermore, the nanoparticle exhibited extraordinary photostability and photothermal therapy capacity exceeded 42 °C within 100 s under 808 nm laser irradiation. Meanwhile, the Fe-GA polymeric network can be disassembled in tumor acidic environment and the released drug GA can induce apoptosis. This study demonstrated that the Fe-GA network-based nanoparticle is a promising diagnostic and therapeutic agent for theranostic application and further clinic translation.

One pot synthesis of water-soluble quercetin derived multifunctional nanoparticles with photothermal and antioxidation capabilities

As a member of flavonoids, the application of quercetin has been mainly focused on antioxidation study. Fabrication of multifunctional nanoplatforms with quercetin is limited. In the present study, water-soluble quercetin derived nanoparticles (QFNPs) were fabricated through the one pot synthesis strategy with Fe³⁺, quercetin and poly (vinyl pyrrolidone) (PVP). The raw materials were dissolved in absolute ethanol and the mixed together. After stirring at room temperature for 6 h, the QFNPs could be simply harvested by centrifugation without the need of time-consuming dialysis procedure. Due to the protective effect of PVP, the synthesized nanoparticles could be well dispersed in water with the hydrodynamic size about 23 nm. DPPH free radical scavenging capacity assay showed QFNPs could act as efficient antioxidant. Besides antioxidation activity, the QFNPs also exhibited good photothermal capacity. Temperature stability result suggested the good stability of QFNPs between 35 and 95 °C. MTT and hemolysis assay showed the good biocompatibility of QFNPs. What's more, the QFNPs showed good cellular antioxidation activity and efficient photothermal killing effect to cancer cells (4T1 cells). The QFNPs could be promising nanoplatform for biomedical application.

A nanoscale photothermal agent based on a metal-organic coordination polymer as a drug-loading framework for effective combination therapy

Metallic materials are widely emerging as photothermal agents owing to their superior photothermal transduction efficiency and satisfactory photostability. In this study, an iron-based coordination polymer (Fe-CNP) loaded with doxorubicin (DOX) was assessed as a dual-function agent for photothermal therapy (PTT) and tumor-targeted chemotherapy. Fe-CNPs were synthesized by a one-step coordination reaction between Fe³⁺, hydrocaffeic acid, and dopamine-modified hyaluronic acid. A drug-loading method was developed to entrap DOX within Fe-CNPs through the formation of coordination bonds by Fe³⁺ and DOX (Scheme 1). DOX release was rapidly triggered in the cellular acidic environment and further enhanced by hyperpyrexia in the part of tumor, which will kill the remaining tumor cells after PTT. Animal experiments demonstrated complete inhibition of tumor growth without recurrence in 21 days after injection of DOX@Fe-CNPs with NIR laser irradiation. These results confirmed the enhanced anti-tumor efficiency of the chemo-photothermal nanosystem. Our work may reveal a photothermal coordination polymer as a drug-loading framework and highlight the development of metal-organic materials in combined chemo-photothermal therapy. STATEMENT OF SIGNIFICANCE: Photothermal therapy (PTT), which could directly act on tumors, has been considered as a promising treatment method for cancer. The combination of PTT with chemotherapy is attracting tremendous attention because such advanced application can achieve personalized precise medicine. Unfortunately, most PTT materials have photobleaching property, which results in reduced photothermal efficiency. Furthermore, their clinical applications also suffer from low loading capacity of chemotherapeutic drugs or nonbiodegradability in the biological system. In this study, we hypothesized that iron-based coordination polymers (Fe-CNPs) could function dually as agents to deliver both PTT and tumor-targeted chemotherapy by coordination loading of the chemotherapeutic drug doxorubicin (DOX). Our work may open up new avenues to rationally design versatile platforms for photothermal-chemotherapy to obtain synergistically enhanced therapeutic efficacy.

Coordinatively Unsaturated Fe3+ Based Activatable Probes for Enhanced MRI and Therapy of Tumors

Exogenous Fe^III can be used for cancer magnetic resonance (MR) imaging and potentially for cancer treatment by a ferroptosis pathway or photothermal ablation. To achieve this, effective and accurate delivery of Fe^III to cancerous sites is critical, requiring a balance of release kinetics of Fe³⁺ in tumorous and normal tissues. A nanoprobe is described consisting of upconversion luminescence (UCL) nanoparticles as a core and a coordinatively unsaturated Fe^III -containing Fe³⁺ /gallic acid complex as a shell. Owing to the introduction of an unsaturated coordination structure, Fe^III in the nanoprobe can be released only in the tumor microenvironment in response to the lightly acidic pH. The multiple UCLs are used for quantitatively visualizing the release of Fe³⁺ in vivo, whilst the release resultant serves as a photothermal agent. This nanoprobe exhibited ligand-free tumor targeting ability, activatable MR imaging performance, and efficacious therapeutic effects against tumors in vivo.

PEGylated rhenium nanoclusters: a degradable metal photothermal nanoagent for cancer therapy

A common issue of functional nanoagents for potential clinical translation is whether they are biodegradable or renal clearable. Previous studies have widely explored noble metal nanoparticles (Au and Pd) as the first generation of photothermal nanoagents for cancer therapy, but all of the reported noble metal nanoparticles are non-degradable. On the other hand, rhenium (Re), one of the noble and precious metals with a high atomic number (Z = 75), has been mainly utilized as a jet superalloy or chemical catalyst, but the biological characteristics and activity of Re nanoparticles have never been evaluated until now. To address these issues, here we report a simple and scalable liquid-reduction strategy to synthesize PEGylated Re nanoclusters, which exhibit intrinsically high photothermal conversion efficacy (33.0%) and high X-ray attenuation (21.2 HU mL mg-1), resulting in excellent photothermal ablation (100% tumor elimination) and higher CT enhancement (15.9 HU mL mg-1 for commercial iopromide in clinics). Impressively, biocompatible Re nanoclusters can degrade into renal clearable ReO4 - ions after exposure to H2O2, and thus achieve much higher renal clearance efficiency than conventional gold nanoparticles. This work reveals the potential of theranostic application of metallic Re nanoclusters with both biodegradation and renal clearance properties and provides insights into the design of degradable metallic platforms with high clinical prospects.

A pH-Sensitive Zwitterionic Iron Complex Probe with High Biocompatibility for Tumor-Specific Magnetic Resonance Imaging

Accurate diagnosis of tumor characteristics, including its location and boundary, is of immense value to subsequent therapy. Activatable magnetic resonance imaging (MRI) contrast agents that respond to tumor-specific microenvironments, such as the redox state, pH, and enzyme activity, enable better mapping of tumor tissue. However, the practical application of most reported activatable agents is hampered by problems including potential toxicity, inefficient elimination, and slow activation. In this study, we developed a zwitterionic iron complex (Fe-ZDS) as a positive MRI contrast agent for tumor-specific imaging. Fe-ZDS could dissociate in weakly acidic solution rapidly, accompanied by clear longitudinal relaxivity (r₁ ) enhancement, which enabled the complex to act as a pH-sensitive contrast agent for tumor-specific MR imaging. In vivo experiments showed that Fe-ZDS rapidly enhanced the tumor-to-normal contrast ratio by >40 %, which assisted in distinguishing the tumor boundary. Furthermore, Fe-ZDS circulated freely in the bloodstream and was excreted relatively safely via kidneys owing to its zwitterionic nature. Therefore, Fe-ZDS is an ideal candidate for a tumor-specific MRI contrast agent and holds considerable potential for clinical translation.

Scalable fabrication of metal-phenolic nanoparticles by coordination-driven flash nanocomplexation for cancer theranostics

Although various nanomaterials have been developed for cancer theranostics, there remains a key challenge for effective integration of therapeutic drugs and diagnostic agents into a single multicomponent nanoparticle via a simple and scalable approach. Moreover, the bottlenecks of nanoformulation in composition controllability, colloidal stability, drug loading capability and batch-to-batch repeatability currently still hinder the clinical translation of nanomedicine. Herein, we report a coordination-driven flash nanocomplexation (cFNC) process to achieve scalable fabrication of doxorubicin-based metal-phenolic nanoparticles (DITH) with a hyaluronic acid surface layer through efficient control of coordination reaction kinetics in a rapid turbulent mixing. The optimized DITH exhibited a small hydrodynamic diameter (84 nm), narrow size distribution, high drug loading capacity (26.6%), high reproducibility and pH-triggered drug release behaviors. The studies indicated that DITH significantly increased cellular endocytosis mediated by CD44+ receptor targeting and accelerated intracellular drug release owing to the sensitivity of DITH to environmental pH stimuli. Furthermore, guided by T1-weighted magnetic resonance (MR) imaging function endowed by ferric ions, DITH exhibited prolonged blood circulation, enhanced tumor accumulation, improved therapeutic performance and decreased toxic side effects after intravenous injection in a MCF-7 tumor-bearing mice model. These results confirmed that the developed DITH is a promising vehicle for cancer theranostic applications, and our work provided a new strategy to promote the development of translational nanomedicine.

On-Demand Detaching Nanosystem for the Spatiotemporal Control of Cancer Theranostics

Engineering multiple theranostic modalities into a single nanoscale entity holds great potential to rejuvenate cancer treatments; however, enabling the sophisticated spatiotemporal control of each component for maximizing theranostic improvement and minimizing side effects concurrently remains a challenge. Herein, an intelligent detachable "nanorocket" is developed to sequentially manipulate and optimize multitheranostic processes for magnetic resonance-assisted ultrasound-drug combined therapy (MR-HIFU-Drug). The "nanorocket" is constructed by integrating multicomponent (MnCO₃, doxorubicin, silica) on the pH-sensitive CaCO₃ nanoparticles step by step via cation exchange and controlled heterogeneous nucleation, in which doxorubicin is encapsulated in both carbonates and silica component. The "nanorocket" can initiate sequential detachment in the acidic tumor microenvironment. Specifically, carbonates decompose instantly, releasing Mn²⁺ as the MR contrast agent and leaving hollow silica nanostructure behind as the HIFU synergistic agent. Consequently, burst release of drug is also triggered, further triggering the degradation of silica, which in turn regulates the slow release of drug from the silica matrix. Thus, efficient tumor inhibition is achieved by enhanced HIFU ablation and biphase release of doxorubicin with a stepwise clearance of Mn and Si. This work establishes a system for the systematic spatiotemporal dispatch of diverse theranostic components for the balance of efficacy and safety in cancer theranostics.

Renal Clearable Bi-Bi2S3 Heterostructure Nanoparticles for Targeting Cancer Theranostics

Recent development of precise nanomedicine has aroused an overwhelming interest in integration of diagnosis and treatment for cancers. Designing renal-clearable and targeting nanoparticles (NPs) has specific cancer theranostic implications and remains a challenging task. In this work, the ultrasmall folic acid (FA) and bovine serum albumin-modified Bi-Bi₂S₃ heterostructure nanoparticles NPs (Bi-Bi₂S₃/BSA&FA NPs) with excellent computed tomography (CT) and photoacoustic imaging abilities and outstanding photothermal performances were synthesized in an aqueous phase route via a simple method. Bi-Bi₂S₃/BSA&FA NPs have the following criteria: (i) Bi-Bi₂S₃/BSA&FA NPs with heterostructure possess better stability than Bi NPs and higher Bi content than Bi₂S₃ NPs, which are conducive to the enhancement of CT imaging effect; (ii) Bi-Bi₂S₃/BSA&FA NPs with FA molecules on the surface could target the tumor site effectively; (iii) Bi-Bi₂S₃/BSA&FA NPs could inhibit tumor growth effectively under 808 nm laser irradiation; (iv) ultrasmall Bi-Bi₂S₃/BSA&FA NPs could be cleared through kidney and liver within a reasonable time, avoiding a long-term retention/toxicity. Therefore, the renal clearable Bi-Bi₂S₃/BSA&FA NPs are a promising agent for targeting cancer theranostics.

Amplification of Tumor Oxidative Stresses with Liposomal Fenton Catalyst and Glutathione Inhibitor for Enhanced Cancer Chemotherapy and Radiotherapy

Amplification of intracellular oxidative stress has been found to be an effective strategy to induce cancer cell death. To this end, we prepare a unique type of ultrasmall gallic acid-ferrous (GA-Fe(II)) nanocomplexes as the catalyst of Fenton reaction to enable persistent conversion of H₂O₂ to highly cytotoxic hydroxyl radicals (•OH). Then, both GA-Fe(II) and l-buthionine sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, are coencapsulated within a stealth liposomal nanocarrier. Interestingly, the obtained BSO/GA-Fe(II)@liposome is able to efficiently amplify intracellular oxidative stress via increasing •OH generation and reducing GSH biosynthesis. After chelating with ^99mTc⁴⁺ radioisotope, such BSO/GA-Fe(II)@liposome could be tracked under in vivo single-photon-emission-computed-tomography (SPECT) imaging, which illustrates the time-dependent tumor homing of such liposomal nanoparticles after intravenous injection. With GA-Fe(II)-mediated •OH production and BSO-mediated GSH depletion, treatment with such BSO/GA-Fe(II)@liposome would lead to dramatically enhanced intratumoral oxidative stresses, which then result in remarkably improved therapeutic efficacies of concurrently applied chemotherapy or radiotherapy. This work thus presents the concise fabrication of biocompatible BSO/GA-Fe(II)@liposome as an effective adjuvant nanomedicine to promote clinically used conventional cancer chemotherapy and radiotherapy, by greatly amplifying the intratumoral oxidative stress.

A dual-inhibitor system for the effective antifibrillation of Aβ40 peptides by biodegradable EGCG–Fe(iii)/PVP nanoparticles

By the synergistic effect of dual inhibition, EFPP NPs exhibited a significant effect on the inhibition of Aβ40 fibrillation and on the disaggregation of existing Aβ40 fibrils.

Facile synthesis of Fe-p-aminophenol nanoparticles for photothermal therapy

Fe-p-aminophenol (Fe-PAP) nanoparticles, a newly developed photothermal agent (PTA), were successfully synthesized via a one-pot method at room temperature.

Template-free synthesis and metalation of hierarchical covalent organic framework spheres for photothermal therapy

Room temperature synthesized hierarchical COF spheres were metalated with Fe³⁺ and utilized for photothermal therapy.

Ultra-small Albumin Templated Gd/Ru Composite Nanodots for In Vivo Dual modal MR/Thermal Imaging Guided Photothermal Therapy

Multifunctional theranostic nanoagents which realize precise diagnosis and treatment of tumors are attracting increasing interests in recent years. However, efficient and controlled synthesis of ultra-small noble metal nanoagents remains a challenge. Here, monodisperse Gd/Ru@BSA nanodots (GRBNDs) are successfully fabricated via a totally "green", "one-pot" protocol for in situ reduction of Ru(III) and biomineralization of Gd(III) in the presence of albumin. The as-prepared nanoagent possesses the features of being ultra small in size (≈6.7 nm), having strong colloidal stability, and thermal stability as well as high photothermal conversion efficiency (η = 50.7%). As expected, the GRBNDs achieve a significant efficacy of anticancer therapy under LASER activation both in vitro and in vivo. It also exhibits superior T₁ -weighted magnetic resonance (MR) imaging ability due to its high longitudinal relaxivity value (r₁ = 10.98 × 10^-3 m^-1 s^-1 ). Moreover, it is demonstrated to be renal clearable with negligible systemic toxicity. This work highlights a straightforward and repeatable approach for synthesizing highly effective and multifunctional noble metal nanoagent of great clinical promising for cancer theranostics.

Paclitaxel-Induced Ultrasmall Gallic Acid-Fe@BSA Self-Assembly with Enhanced MRI Performance and Tumor Accumulation for Cancer Theranostics

Ultrasmall nanoparticles have attracted great attention because of their efficient renal clearance. However, their bioapplication is still severely hampered by the poor performance derived from low tumor accumulation. Here, a large, self-assembled nanoparticle was designed for cancer theranostics and used with paclitaxel (PTX) to assemble bovine serum albumin-coated ultrasmall gallic acid-Fe(III) (GA-Fe@BSA-PTX) nanoparticles by the hydrophobic effect. The GA-Fe@BSA-PTX self-assembled nanoparticles featured appropriate size (∼115 nm), high water dispersity and stability, and low cell toxicity. Importantly, the magnetic resonance imaging performance and tumor accumulation of GA-Fe@BSA-PTX self-assembled nanoparticles were much better than those of the ultrasmall GA-Fe@BSA nanoparticles. Furthermore, the GA-Fe@BSA-PTX self-assembled nanoparticles exhibited an excellent therapeutic effect on tumors, owing to the combined chemo- and photothermal effects. This work highlights the great potential of the as-synthesized GA-Fe@BSA-PTX self-assembled nanoparticles as a multifunctional theranostic nanoplatform, offering compelling opportunities for theranostic applications in the clinic.

Multifunctional Theranostic Nanoparticles Derived from Fruit-Extracted Anthocyanins with Dynamic Disassembly and Elimination Abilities

Low toxic theranostic nanoparticles that can simultaneously achieve effective tumor accumulation and rapid renal clearance are highly desired for imaging contrast agents and photothermal therapy (PTT) in tumor diagnosis and therapy. Herein, we report a one-pot method for preparing multifunctional nanoparticles (FeAP-NPs) based on the coordination interaction of natural polyphenols (anthocyanins) extracted from fruits, Fe^III ions, and poly(l-glutamic acid)- g-methoxy poly(ethylene glycol) copolymers. The FeAP-NPs possess the following favorable advantages: (1) The components of FeAP-NPs originate from natural products, an endogenous element, and poly(amino acid) derivatives, guaranteeing their safety for in vivo application. (2) FeAP-NPs exhibit excellent dual photoacoustic (PA)/magnetic resonance (MR) imaging capacity and high photothermal efficiency. (3) FeAP-NPs can overcome the intractable dilemma of the enhanced permeability and retention (EPR) effect and renal clearance for nanomedicine through the dynamic disassembling ability, which induces a switch of the elimination pathway. Complete tumor ablation is realized by PTT in MCF-7-bearing nude mice under the precise guide of PA and MR imaging. The detailed evaluation of the safety, biodistribution, and elimination behaviors of FeAP-NPs is conducted in vitro or in vivo. This work provides a promising comprehensive solution for nanomedicine clinical application.

A bottom-up synthesis of rare-earth-hydrotalcite monolayer nanosheets toward multimode imaging and synergetic therapy

Recently, ultrathin two-dimensional (2D) nanomaterials have attracted considerable research interest in biomedical applications, owing to their intriguing quantum size and surface effects. In this work, a one-step "bottom-up" method is developed to prepare rare-earth (Gd3+ and Yb3+) co-doped layered double hydroxide (LDH) monolayer nanosheets, with a precisely controlled composition and uniform morphology. Due to the successful introduction of Gd3+ and Yb3+ into the LDH host layer, the Gd&Yb-LDH monolayer nanosheets exhibit excellent magnetic resonance (MR)/X-ray computed tomography (CT) dual-mode imaging functionality. Moreover, the Gd&Yb-LDH monolayer nanosheets achieve an ultrahigh loading of a chemotherapeutic drug (SN38) with a loading content (LC) of 925%, which is a one order of magnitude enhancement compared with previously reported delivery systems of hydrophobic drugs. Interestingly, by further combination with indocyanine green (ICG), in vivo tri-mode imaging, including CT, MR and near infrared fluorescence (NIRF) imaging, is achieved, which enables a noninvasive visualization of cancer cell distribution with deep spatial resolution and high sensitivity. In addition, in vitro and in vivo therapeutic evaluations demonstrate an extremely high tri-mode synergetic anticancer activity and superior biocompatibility of SN38&ICG/Gd&Yb-LDH. Therefore, this work demonstrates a paradigm for the synthesis of novel multifunctional 2D monolayer materials via a facile "bottom-up" route, which shows promising applications in cancer synergetic theranostics.

Accurate Monitoring of Renal Injury State through in Vivo Magnetic Resonance Imaging with Ferric Coordination Polymer Nanodots

It is highly challenging to detect the pathophysiology of the diseased kidneys and achieve precise diagnosis because there are few in vivo noninvasive imaging techniques to quantitatively assess kidney dysfunction. This longstanding challenge is normally attributed to the limited molecular contrast agents which can be addressed with renal clearable nanoprobes. In this report, we demonstrate the use of magnetic resonance imaging along with renal clearable ferric coordination polymer nanodots (Fe-CPNDs) for in vivo monitoring the kidney dysfunction effects following drug (daunomycin)-induced kidney injury. After intravenous injection of Fe-CPNDs, the change of the MR signal in the kidney can be precisely correlated with local pathological lesion which is demonstrated by renal anatomic details and biochemical examinations of urine and blood. This finding opens the door to the possibility of noninvasively assessing kidney dysfunction and local injuries.

Monolayer Nanosheets with an Extremely High Drug Loading toward Controlled Delivery and Cancer Theranostics

2D nanomaterials have attracted considerable research interest in drug delivery systems, owing to their intriguing quantum size and surface effect. Herein, Gd³⁺ -doped monolayered-double-hydroxide (MLDH) nanosheets are prepared via a facile bottom-up synthesis method, with a precisely controlled composition and uniform morphology. MLDH nanosheets as drug carrier are demonstrated in coloading of doxorubicin and indocyanine green (DOX&ICG), with an ultrahigh drug loading content (LC) of 797.36% and an encapsulation efficiency (EE) of 99.67%. This is, as far as it is known, the highest LC level at nearly 100% of EE among previously reported 2D drug delivery systems so far. Interestingly, the as-prepared DOX&ICG/MLDH composite material shows both pH-controlled and near-infrared-irradiation-induced DOX release, which holds a promise in stimulated drug release. An in vivo dual-mode imaging, including near-infrared fluorescence and magnetic resonance imaging, enables a noninvasive visualization of distribution profiles at the tumor site. In addition, in vitro and in vivo therapeutic evaluations demonstrate an excellent trimode synergetic anticancer activity and superior biocompatibility of DOX&ICG/MLDH. Therefore, MLDH nanosheets provide new perspectives in the design of multifunctional nanomedicine, which shows promising applications in controlled drug delivery and cancer theranostics.