Blood-triggered generation of platinum nanoparticle functions as an anti-cancer agent

Liquid exfoliation of molybdenum metallenes for non-inflammatory photothermal therapy of tumors

Tissue damage and cell death occurring during photothermal therapy (PTT) for tumors can induce an inflammatory response that is detrimental to tumor therapy. Herein, ultrathin Mo metallene nanosheets with a thickness of <5 nm prepared by liquid phase exfoliation were explored as functional hyperthermia agents for non-inflammatory ablation of tumors. The obtained Mo metallene nanosheets exhibited good photothermal conversion properties and significant reactive oxygen species (ROS) scavenging ability, thus achieving superior cancer cell ablation and anti-inflammatory effects in vitro. For in vivo experiments, 4T1 tumors were ablated while the inflammation-related cytokine levels did not obviously increase, demonstrating that the inflammatory response induced by PTT was inhibited by the anti-inflammatory properties of Mo metallene nanosheets. Moreover, Mo metallene nanosheets depicted good dispersibility and biocompatibility, beneficial for biomedical applications. This work introduces Mo metallenes as promising hyperthermia agents for non-inflammatory PTT of tumors.

Photo-induced Oriented Crystallization of Intracellular Nanocrystals Based on Phase Separation for Diagnostic Bioimaging and Analysis

Biomineral crystals form complex nonequilibrium structures based on the multistep nucleation theory, via transient amorphous precursors. However, the intricate nature of the biological system results in the inconsistent frequency of nucleation and crystallization, which making it problematic to obtain homogeneous nanocrystals, limits their application in biomedicine. Here, it is reported that homogeneous nanocrystals of photoinduced oriented crystallization with protein coronas are based on intracellular liquid-liquid phase separation for in situ analysis and mapping of surface-enhanced Raman spectroscopy (SERS). Near-infrared light promotes the formation of intracellular dense phases, accelerates the nucleation of gold atoms at secondary structure sites of proteins, and promotes the growth of crystals. Homogeneous gold nanocrystals with stable SERS signals can be used to analysis different cell cycles and acquire in situ molecular information of metastatic tumor cells. Of note are tag molecule is embedded in protein coronas of gold nanocrystals to enable the mapping of patient tumor tissue samples and the portable recognition of tumor cells. Thus, this study proposes a new strategy for biomineralization of intracellular homogeneous gold nanocrystals and its potential application.

Palladium Metal Nanocomposites Based on PEI-Functionalized Nitrogen-Doped Graphene Quantum Dots: Synthesis, Characterization, Density Functional Theory Modeling, and Cell Cycle Arrest Effects on Human Ovarian Cancer Cells

In this study, the synthesis, characterization, density functional theory calculations (DFT), and effect of polyethylenimine (PEI)-functionalized nitrogen-doped graphene quantum dots (PEI N-GQDs) and their palladium metal nanoparticles nanocomposites (PdNPs/PEI N-GQDs) on cancer cells were extensively investigated. The focus also includes investigating their cytotoxic and apoptotic effects on ovarian cancer cells, which pose a serious risk to women's health and have high death rates from delayed diagnosis, inadequate response to treatment, and decreased survival. Graphene quantum dots and their palladium nanocomposites were differentially effective against ovarian cancer cell lines. In particular, the smaller particle size and morphology of PdNPs/PEI N-GQDs nanocomposites compared with PEI N-GQDs probably enhance their activity through highly improved uptake by cells. These findings emphasize the importance of particle size in composite drugs for efficient cancer treatment. DFT results revealed that the Pd-containing nanocomposite, with a smaller highest occupied molecular orbital-lowest unoccupied molecular orbital gap, exhibited higher reactivity and anticancer effects in human ovarian cancer cell line, OVCAR-3. Significantly, the application of nanocomposites to ovarian cancer cells initiated apoptosis, offering valuable insights into the intricate interplay between nanomaterials and cancer biology.

Adjuvant Novel Nanocarrier-Based Targeted Therapy for Lung Cancer

Lung cancer has the lowest survival rate due to its late-stage diagnosis, poor prognosis, and intra-tumoral heterogeneity. These factors decrease the effectiveness of treatment. They release chemokines and cytokines from the tumor microenvironment (TME). To improve the effectiveness of treatment, researchers emphasize personalized adjuvant therapies along with conventional ones. Targeted chemotherapeutic drug delivery systems and specific pathway-blocking agents using nanocarriers are a few of them. This study explored the nanocarrier roles and strategies to improve the treatment profile's effectiveness by striving for TME. A biofunctionalized nanocarrier stimulates biosystem interaction, cellular uptake, immune system escape, and vascular changes for penetration into the TME. Inorganic metal compounds scavenge reactive oxygen species (ROS) through their photothermal effect. Stroma, hypoxia, pH, and immunity-modulating agents conjugated or modified nanocarriers co-administered with pathway-blocking or condition-modulating agents can regulate extracellular matrix (ECM), Cancer-associated fibroblasts (CAF),Tyro3, Axl, and Mertk receptors (TAM) regulation, regulatory T-cell (Treg) inhibition, and myeloid-derived suppressor cells (MDSC) inhibition. Again, biomimetic conjugation or the surface modification of nanocarriers using ligands can enhance active targeting efficacy by bypassing the TME. A carrier system with biofunctionalized inorganic metal compounds and organic compound complex-loaded drugs is convenient for NSCLC-targeted therapy.

Computational understanding of the coalescence of metallic nanoparticles: a mini review

Metallic nanoparticles exhibit extraordinary properties that differ from those of bulk materials due to their large surface area to volume ratios. Coalescence of metallic nanoparticles has a huge impact on their properties. Remarkable progress has been made by using computational methods for understanding nanoparticle coalescence. This work aims to provide a mini review on the state-of-the-art modelling and simulation of nanoparticle coalescence. First, we will discuss the outstanding performances and coalescence behaviors of metallic nanoparticles, and list some challenges in the coalescence of metallic nanoparticles. Next, we will introduce the applications of molecular dynamics and the Monte Carlo method in nanoparticle coalescence. Furthermore, we will discuss the coalescence kinetics and mechanisms of metal nanoparticles with the same element and different elements, alloy nanoparticles and metal oxide nanoparticles. Finally, we will present our perspective and conclusion.

Pt(IV) Complexes in the Search for Novel Platinum Prodrugs with Promising Activity

The kinetically inert, six coordinated, octahedral Pt(IV) complexes are termed dual-, triple-, or multi-action prodrugs based on the nature of the axially substituted ligands. These ligands are either inert or biologically active, where the nature of these axial ligands provides additional stability, synergistic biological activity or cell-targeting ability. There are many literature reports from each of these classes, mentioning the varied nature of these axial ligands. The ligands comprise drug molecules such as chlorambucil, doxorubicin, valproic acid, ethacrynic acid, biologically active chalcone, coumarin, combretastatin, non-steroidal anti-inflammatory drugs (NSAIDs) and many more, potentiating the anti-proliferative profile or reducing the side effects associated with cisplatin therapy. The targeting and non-targeting nature of these moieties exert additive or synergistic effects on the anti-cancer activity of Pt(II) moieties. Herein, we discuss the effects of these axially oriented ligands and the changes in the non-leaving am(m)ine groups and in the leaving groups on the biological activity. In this review, we have presented the latest developments in the field of Pt(IV) complexes that display promising activity with a reduced resistance profile. We have discussed the structure activity relationship (SAR) and the effects of the ligands on the biological activity of Pt(IV) complexes with cisplatin, oxaliplatin, carboplatin and the Pt core other than approved drugs. This literature work will help researchers to get an idea about Pt(IV) complexes that have been classified based on the aspects of their biological activity.

Photo-Driven In Situ Solidification of Whole Cells through Inhibition of Trogocytosis for Immunotherapy

Achieving antitumor immunotherapy based on hybridization of multiple types of inactivated cells has attracted a lot of attention. However, the hybridized cells of disordered structure could result in the shedding of antigens and their transfer to immune cells, which suppresses tumor immunity through trogocytosis. Here, we report a strategy for in situ solidification of tumor whole cell by biomineralization for sustained stimulation of antitumor immunity. The near-infrared light was used to accelerate the breaking of Au=P bonds in auranofin, and the exposed Au atoms biomineralize at the secondary structure (β-corner) of the protein to form Au nanocrystals with in situ protein coronas in tumor cells. Au nanocrystals are anchored to the tumor cells through protein coronas, which fixes the morphology and antigens of whole tumor cells, rendering them physiologically inactive. Interestingly, this solidified tumor cell prevents immune cells from undergoing trogocytosis, which inhibits proximal and distal tumor growth. Thus, this study presents the strategy of solidified cells and its potential application in tumor immunotherapy.

Use of Albumin for Drug Delivery as a Diagnostic and Therapeutic Tool

Drug delivery is an important topic that has attracted the attention of researchers in recent years. Albumin nanoparticles play a significant role in drug delivery as a carrier due to their unique characteristics. Albumin is non-toxic, biocompatible, and biodegradable. Its structure is such that it can interact with different drugs, which makes the treatment of the disease faster and also reduces the side effects of the drug. Albumin nanoparticles can be used in the diagnosis and treatment of many diseases, including cancer, diabetes, Alzheimer's, etc. These nanoparticles can connect to some compounds, such as metal nanoparticles, antibodies, folate, etc. and create a powerful nanostructure for drug delivery. In this paper, we aim to investigate albumin nanoparticles in carrier format for drug delivery application. In the beginning, different types of albumin and their preparation methods were discussed, and then albumin nanoparticles were discussed in detail in diagnosing and treating various diseases.

Deep Insight of Design, Mechanism, and Cancer Theranostic Strategy of Nanozymes

Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007, nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity, low cost, mild reaction conditions, good stability, and suitable for large-scale production. Recently, with the cross fusion of nanomedicine and nanocatalysis, nanozyme-based theranostic strategies attract great attention, since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects. Thus, various nanozymes have been developed and used for tumor therapy. In this review, more than 270 research articles are discussed systematically to present progress in the past five years. First, the discovery and development of nanozymes are summarized. Second, classification and catalytic mechanism of nanozymes are discussed. Third, activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory, machine learning, biomimetic and chemical design. Then, synergistic theranostic strategy of nanozymes are introduced. Finally, current challenges and future prospects of nanozymes used for tumor theranostic are outlined, including selectivity, biosafety, repeatability and stability, in-depth catalytic mechanism, predicting and evaluating activities.

Intelligent nanomaterials for cancer therapy: recent progresses and future possibilities

Intelligent nanomedicine is currently one of the most active frontiers in cancer therapy development. Empowered by the recent progresses of nanobiotechnology, a new generation of multifunctional nanotherapeutics and imaging platforms has remarkably improved our capability to cope with the highly heterogeneous and complicated nature of cancer. With rationally designed multifunctionality and programmable assembly of functional subunits, the in vivo behaviors of intelligent nanosystems have become increasingly tunable, making them more efficient in performing sophisticated actions in physiological and pathological microenvironments. In recent years, intelligent nanomaterial-based theranostic platforms have showed great potential in tumor-targeted delivery, biological barrier circumvention, multi-responsive tumor sensing and drug release, as well as convergence with precise medication approaches such as personalized tumor vaccines. On the other hand, the increasing system complexity of anti-cancer nanomedicines also pose significant challenges in characterization, monitoring and clinical use, requesting a more comprehensive and dynamic understanding of nano-bio interactions. This review aims to briefly summarize the recent progresses achieved by intelligent nanomaterials in tumor-targeted drug delivery, tumor immunotherapy and temporospatially specific tumor imaging, as well as important advances of our knowledge on their interaction with biological systems. In the perspective of clinical translation, we have further discussed the major possibilities provided by disease-oriented development of anti-cancer nanomaterials, highlighting the critical importance clinically-oriented system design.

Biogenic Copper Selenide Nanoparticles for Near-Infrared Photothermal Therapy Application

Near-infrared (NIR) photothermal therapy (PTT) is attractive for cancer treatment but is currently restricted by limited availability and insufficient NIR-II photoactivity of photothermal agents, for which artificial nanomaterials are usually used. Here, we report the first use of biogenic nanomaterials for PTT application. A fine-controlled extracellular biosynthesis of copper selenide nanoparticles (bio-Cu_2-xSe) by Shewanella oneidensis MR-1 was realized. The resulting bio-Cu_2-xSe, with fine sizes (∼35.5 nm) and high product purity, exhibited 76.9% photothermal conversion efficiency under 1064 nm laser irradiation, outperforming almost all the existing counterparts. The protein capping also imparted good biocompatibility to bio-Cu_2-xSe to favor a safe PTT application. The in vivo PTT with injected bio-Cu_2-xSe in mice (without extraction nor further modification) showed 87% tumor ablation without impairing the normal organisms. Our work not only opens a green route to synthesize the NIR-II photothermal nanomaterial but may also lay a basis for the development of bacteria-nanomaterial hybrid therapy technologies.

Nanomaterial-Based Antivascular Therapy in the Multimodal Treatment of Cancer

Abnormal tumor vasculature and a hypoxic tumor microenvironment (TME) limit the effectiveness of conventional cancer treatment. Recent studies have shown that antivascular strategies that focus on antagonizing the hypoxic TME and promoting vessel normalization effectively synergize to increase the antitumor efficacy of conventional therapeutic regimens. By integrating multiple therapeutic agents, well-designed nanomaterials exhibit great advantages in achieving higher drug delivery efficiency and can be used as multimodal therapy with reduced systemic toxicity. In this review, strategies for the nanomaterial-based administration of antivascular therapy combined with other common tumor treatments, including immunotherapy, chemotherapy, phototherapy, radiotherapy, and interventional therapy, are summarized. In particular, the administration of intravascular therapy and other therapies with the use of versatile nanodrugs is also described. This review provides a reference for the development of multifunctional nanotheranostic platforms for effective antivascular therapy in combined anticancer treatments.

Self-Therapeutic Nanomaterials: Applications in Biology and Medicine

Over past decades, nanotechnology has contributed to the biomedical field in areas including detection, diagnosis, and drug delivery via opto-electronic properties or enhancement of biological effects. Though generally considered inert delivery vehicles, a plethora of past and present evidence demonstrates that nanomaterials also exude unique intrinsic biological activity based on composition, shape, and surface functionalization. These intrinsic biological activities, termed self-therapeutic properties, take several forms, including mediation of cell-cell interactions, modulation of interactions between biomolecules, catalytic amplification of biochemical reactions, and alteration of biological signal transduction events. Moreover, study of biomolecule-nanomaterial interactions offers a promising avenue for uncovering the molecular mechanisms of biology and the evolution of disease. In this review, we observe the historical development, synthesis, and characterization of self-therapeutic nanomaterials. Next, we discuss nanomaterial interactions with biological systems, starting with administration and concluding with elimination. Finally, we apply this materials perspective to advances in intrinsic nanotherapies across the biomedical field, from cancer therapy to treatment of microbial infections and tissue regeneration. We conclude with a description of self-therapeutic nanomaterials in clinical trials and share our perspective on the direction of the field in upcoming years.

Mechanical Stability of Nano-Coatings on Clinically Applicable Electrodes, Generated by Electrophoretic Deposition

The mechanical stability of implant coatings is crucial for medical approval and transfer to clinical applications. Here, electrophoretic deposition (EPD) is a versatile coating technique, previously shown to cause significant post-surgery impedance reduction of brain stimulation platinum electrodes. However, the mechanical stability of the resulting coating has been rarely systematically investigated. In this work, pulsed-DC EPD of laser-generated platinum nanoparticles (PtNPs) on Pt-based, 3D neural electrodes is performed and the in vitro mechanical stability is examined using agarose gel, adhesive tape, and ultrasonication-based stress tests. EPD-generated coatings are highly stable inside simulated brain environments represented by agarose gel tests as well as after in vivo stimulation experiments. Electrochemical stability of the NP-modified surfaces is tested via cyclic voltammetry and that multiple scans may improve coating stability could be verified, indicated by higher signal stability following highly invasive adhesive tape stress tests. The brain sections post neural stimulation in rats are analyzed via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Measurements reveal higher levels of Pt near the region stimulated with coated electrodes, in comparison to uncoated controls. Even though local concentrations in the vicinity of the implanted electrode are elevated, the total Pt mass found is below systemic toxicologically relevant concentrations.

A nuclease-mimetic platinum nanozyme induces concurrent DNA platination and oxidative cleavage to overcome cancer drug resistance

Platinum (Pt) resistance in cancer almost inevitably occurs during clinical Pt-based chemotherapy. The spontaneous nucleotide-excision repair of cancer cells is a representative process that leads to Pt resistance, which involves the local DNA bending to facilitate the recruitment of nucleotide-excision repair proteins and subsequent elimination of Pt-DNA adducts. By exploiting the structural vulnerability of this process, we herein report a nuclease-mimetic Pt nanozyme that can target cancer cell nuclei and induce concurrent DNA platination and oxidative cleavage to overcome Pt drug resistance. We show that the Pt nanozyme, unlike cisplatin and conventional Pt nanoparticles, specifically induces the nanozyme-catalyzed cleavage of the formed Pt-DNA adducts by generating in situ reactive oxygen species, which impairs the damage recognition factors-induced DNA bending prerequisite for nucleotide-excision repair. The recruitment of downstream effectors of nucleotide-excision repair to DNA lesion sites, including xeroderma pigmentosum groups A and F, is disrupted by the Pt nanozyme in cisplatin-resistant cancer cells, allowing excessive accumulation of the Pt-DNA adducts for highly efficient cancer therapy. Our study highlights the potential benefits of applying enzymatic activities to the use of the Pt nanomedicines, providing a paradigm shift in DNA damaging chemotherapy.

Sustainable Bioengineering of Gold Structured Wide-Area Supported Catalysts for Hand-Recyclable Ultra-Efficient Heterogeneous Catalysis

Metal nanoparticles grafted within inert and porous wide-area supports are emerging as recyclable, sustainable catalysts for modern industry applications. Here, we bioengineered gold nanoparticle-based supported catalysts by utilizing the innate metal binding and reductive potential of eggshell as a sustainable strategy. Variable hand-recyclable wide-area three-dimensional catalysts between ∼80 ± 7 and 0.5 ± 0.1 cm² are generated simply by controlling the size of the support. The catalyst possessed high-temperature stability (300 °C) and compatibility toward polar and nonpolar solvents, electrolytes, acids, and bases facilitating ultra-efficient catalysis of accordingly suspended substrates. Validation was done by large-volume (2.8 liters) dye detoxification, gram-scale hydrogenation of nitroarene, and the synthesis of propargylamine. Moreover, persistent recyclability, monitoring of reaction kinetics, and product intermediates are possible due to physical retrievability and interchangeability of the catalyst. Finally, the bionature of the support permits ∼76.9 ± 8% recovery of noble gold simply by immersing in a royal solution. Our naturally created, low-cost, scalable, hand-recyclable, and resilient supported mega-catalyst dwarfs most challenges for large-scale metal-based heterogeneous catalysis.

Green Synthesis of Platinum Nanoparticles for Biomedical Applications

The diverse biological properties of platinum nanoparticles (PtNPs) make them ideal for use in the development of new tools in therapy, diagnostics, and other biomedical purposes. "Green" PtNPs synthesis is of great interest as it is eco-friendly, less energy-consuming and minimizes the amount of toxic by-products. This review is devoted to the biosynthesis properties of platinum nanoparticles based on living organisms (bacteria, fungi, algae, and plants) use. The participation of various biological compounds in PtNPs synthesis is highlighted. The biological activities of "green" platinum nanoparticles (antimicrobial, anticancer, antioxidant, etc.), the proposed mechanisms of influence on target cells and the potential for their further biomedical application are discussed.

Exosomes loaded with ultrasmall Pt nanoparticles: a novel low-toxicity alternative to cisplatin

Background

Platinum nanoparticles have been demonstrated to have excellent anticancer properties. However, because of the lack of specificity they must be delivered to the tumor in amounts sufficient to reach the desired therapeutic objectives. Interestingly, exosomes are considered as excellent natural selective delivery nanotools, but until know their targeting properties have not being combined with the anticancer properties of platinum nanoparticles.

Results

In this work we combine the targeting capabilities of exosomes and the antitumoral properties of ultrasmall (< 2 nm) platinum nanoparticles as a novel, low toxicity alternative to the use of cisplatin. A mild methodology based on the room temperature CO-assisted in situ reduction of Pt2+ precursor was employed to preserve the integrity of exosomes, while generating ultrasmall therapeutic PtNPs directly inside the vesicles. The resulting PtNPs-loaded exosomes constitute a novel hybrid bioartificial system that was readily internalized by the target cells inducing antiproliferative response, as shown by flow cytometry and microscopy experiments in vitro. In vivo Pt-Exos showed antitumoral properties similar to that of cisplatin but with a strongly reduced or in some cases no toxic effect, highlighting the advantages of this approach and its potential for translation to the clinic.

Conclusions

In this study, a nanoscale vector based on ultrasmall PtNPs and exosomes has been created exhibiting antitumoral properties comparable or higher to those of the FDA approved cisplatin. The preferential uptake of PtNPs mediated by exosomal transfer between certain cell types has been exploited to create a selective antitumoral novel bioartificial system. We have demonstrated their anticancer properties both in vitro and in vivo comparing the results obtained with the administration of equivalent amounts of cisplatin, and showing a spectacular reduction of toxicity.

Biosynthesized Gold, Silver, Palladium, Platinum, Copper, and Other Transition Metal Nanoparticles

Nanomedicine is a potential provider of novel therapeutic and diagnostic routes of treatment. Considering the development of multidrug resistance in pathogenic bacteria and the commonness of cancer, novel approaches are being sought for the safe and efficient synthesis of new nanoparticles, which have multifaceted applications in medicine. Unfortunately, the chemical synthesis of nanoparticles raises justified environmental concerns. A significant problem in their widespread use is also the toxicity of compounds that maintain nanoparticle stability, which significantly limits their clinical use. An opportunity for their more extensive application is the utilization of plants, fungi, and bacteria for nanoparticle biosynthesis. Extracts from natural sources can reduce metal ions in nanoparticles and stabilize them with non-toxic extract components.

Combining confocal microscopy, dSTORM, and mass spectroscopy to unveil the evolution of the protein corona associated with nanostructured lipid carriers during blood-brain barrier crossing

Upon coming into contact with the biological environment, nanostructures are immediately covered by biomolecules, particularly by proteins forming the so-called "protein corona" (PC). The phenomenon of PC formation has gained great attention in recent years due to its implication in the use of nanostructures in biomedicine. In fact, it has been shown that the formation of the PC can impact the performance of nanostructures by reducing their stability, causing aggregation, increasing their toxicity, and providing unexpected and undesired nanostructure-cell interactions. In this work, we decided to study for the first time the formation and the evolution of PC on the surface of nanostructured lipid carriers loaded with superparamagnetic iron oxide nanoparticles, before and after the crossing of an in vitro model of the blood-brain barrier (BBB). Combining confocal microscopy, direct STochastic Optical Reconstruction Microscopy (dSTORM), and proteomic analysis, we were able to carry out a complete analysis of the PC formation and evolution. In particular, we highlighted that PC formation is a fast process, being formed around particles even after just 1 min of exposure to fetal bovine serum. Moreover, PC formed around particles is extremely heterogeneous: while some particles have no associated PC at all, others are completely covered by proteins. Lastly, the interaction with an in vitro BBB model strongly affects the PC composition: in particular, a large amount of the proteins forming the initial PC is lost after the BBB passage and they are partially replaced by new proteins derived from both the brain endothelial cells and the cell culture medium. Altogether, the obtained data could potentially provide new insights into the design and fabrication of lipid nanostructures for the treatment of central nervous system disorders.

The Yin and Yang of the protein corona on the delivery journey of nanoparticles

Nanoparticles-based drug delivery systems have attracted significant attention in biomedical fields because they can deliver loaded cargoes to the target site in a controlled manner. However, tremendous challenges must still be overcome to reach the expected targeting and therapeutic efficacy in vivo. These challenges mainly arise because the interaction between nanoparticles and biological systems is complex and dynamic and is influenced by the physicochemical properties of the nanoparticles and the heterogeneity of biological systems. Importantly, once the nanoparticles are injected into the blood, a protein corona will inevitably form on the surface. The protein corona creates a new biological identity which plays a vital role in mediating the bio-nano interaction and determining the ultimate results. Thus, it is essential to understand how the protein corona affects the delivery journey of nanoparticles in vivo and what we can do to exploit the protein corona for better delivery efficiency. In this review, we first summarize the fundamental impact of the protein corona on the delivery journey of nanoparticles. Next, we emphasize the strategies that have been developed for tailoring and exploiting the protein corona to improve the transportation behavior of nanoparticles in vivo. Finally, we highlight what we need to do as a next step towards better understanding and exploitation of the protein corona. We hope these insights into the "Yin and Yang" effect of the protein corona will have profound implications for understanding the role of the protein corona in a wide range of nanoparticles.

Rhodium-Tellurium Nanorod Synthesis Using Galvanic Replacement-Polyol Regrowth for Thermo-Dynamic Dual-Modal Cancer Phototherapy

Rh is a noble metal introduced in bioapplications, including diagnosis and therapy, in addition to its consolidated utilization in organic catalysis and electrocatalysis. Herein, we designed the synthesis of highly crystalline Rh nanocrystal-decorated Rh-Te nanorods (RhTeNRs) through galvanic replacement of sacrificial Te nanorod (TeNR) templates and subsequent polyol regrowth. The obtained RhTeNRs showed excellent colloidal stability and efficient heat dissipation and photocatalytic activity under various laser irradiation wavelengths. Based on the confirmed biocompatibility, RhTeNRs were introduced into in vitro and in vivo cancer phototherapies. The results confirmed the selective physical death of cancer cells in the local area through laser irradiation. While chemotherapy does not guarantee successful treatment due to side effects and resistance, phototherapy using heat and reactive oxygen species generation of RhTeNRs induces physical death.

Influence of protein corona on the interaction of glycogen-siRNA constructs with ex vivo human blood immune cells

Glycogen-nucleic acid constructs i.e., glycoplexes are emerging promising platforms for the alteration of gene expression and transcription. Understanding the interaction of glycoplexes with human blood components, such as serum proteins and peripheral blood mononuclear cells (PBMCs), is important to overcome immune cell activation and control biodistribution upon administration of the glycoplexes in vivo. Herein, we investigated the interactions of polyethylene glycol (PEG)ylated and non-PEGylated glycoplexes carrying siRNA molecules with PBMCs isolated from the blood of healthy donors. We found that both types of glycoplexes were non-toxic and were primarily phagocytosed by monocytes without triggering a pro-inflammatory interleukin 6 cytokine production. Furthermore, we investigated the role of the protein corona on controlling the internalization efficiency in immune cells - we found that the adsorption of serum proteins, in particular haptoglobin, alpha-1-antitrypsin and apolipoprotein A-II, onto the non-PEGylated glycoplexes, significantly reduced the uptake of the glycoplexes by PBMCs. Moreover, the non-PEGylated glycoplexes were efficient in the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) knockdown in monocytic THP-1 cell line. This study provides an insight into the rational design of glycogen-based nanocarriers for the safe delivery of siRNA without eliciting unwanted immune cell activation and efficient siRNA activity upon its delivery.

Platinum nanoplatforms: classic catalysts claiming a prominent role in cancer therapy

Platinum nanoparticles (Pt NPs) have a well-established role as a classic heterogeneous catalyst. Also, Pt has traditionally been employed as a component of organometallic drug formulations for chemotherapy. However, a new role in cancer therapy is emerging thanks to its outstanding catalytic properties, enabling novel approaches that are surveyed in this review. Herein, we critically discuss results already obtained and attempt to ascertain future perspectives for Pt NPs as catalysts able to modify key processes taking place in the tumour microenvironment (TME). In addition, we explore relevant parameters affecting the cytotoxicity, biodistribution and clearance of Pt nanosystems. We also analyze pros and cons in terms of biocompatibility and potential synergies that emerge from combining the catalytic capabilities of Pt with other agents such as co-catalysts, external energy sources (near-infrared light, X-ray, electric currents) and conventional therapies.

Ultraprecise Real-Time Monitoring of Single Cells in Tumors in Response to Metal Ion-Mediated RNA Delivery

With the deepening of cancer clinical research, miRNAs provide new ideas for molecular diagnosis and treatment of tumors. Improving the molecular delivery efficiency of miRNA is the key to the success of miRNA therapy. We have established self-assembly diagnosis and treatment technologies that can be used to achieve accurate targeting and "cargo" delivery at the cellular level. This technology builds a miRNA (let-7a) delivery system based on metal precursor [Au(III) and Fe(II)]-mediated tumor microenvironmental response to realize the self-assembly of Au&Fe-miRNA complexes for precise real-time imaging of tumor cells and targeted therapy. To accurately measure the changes in reactive oxygen species during complex formation in real time at the single-cell level, we employed small-size nanoscale devices as analytical tools. This study proposes an electrochemical sensor based on carbon fiber electrodes for ultraprecise and multiple monitoring of metal-ion-mediated miRNA delivery systems, precisely realizing targeted tracking of tumors and effective intervention inhibition.

Brain Co-Delivery of Temozolomide and Cisplatin for Combinatorial Glioblastoma Chemotherapy

Glioblastoma (GBM) is an intractable malignancy with high recurrence and mortality. Combinatorial therapy based on temozolomide (TMZ) and cisplatin (CDDP) shows promising potential for GBM therapy in clinical trials. However, significant challenges include limited blood-brain-barrier (BBB) penetration, poor targeting of GBM tissue/cells, and systemic side effects, which hinder its efficacy in GBM therapy. To surmount these challenges, new GBM-cell membrane camouflaged and pH-sensitive biomimetic nanoparticles (MNPs) inspired by the fact that cancer cells readily pass the BBB and localize with homologous cells, are developed. This study's results show that MNPs can efficiently co-load TMZ and CDDP, transport these across the BBB to specifically target GBM. Incorporation of pH-sensitive polymer then allows for controlled release of drug cargos at GBM sites for combination drug therapy. Mice bearing orthotopic U87MG or drug-resistant U251^R GBM tumor and treated with MNPs@TMZ+CDDP show a potent anti-GBM effect, greatly extending the survival time relative to mice receiving single-drug loaded nanoparticles. No obvious side effects are apparent in histological analyses or blood routine studies. Considering these results, the study's new nanoparticle formulation overcomes multiple challenges currently limiting the efficacy of combined TMZ and CDDP GBM drug therapy and appears to be a promising strategy for future GBM combinatorial chemotherapy.

An Overview of the Importance of Transition-Metal Nanoparticles in Cancer Research

Several authorities have implied that nanotechnology has a significant future in the development of advanced cancer therapies. Nanotechnology makes it possible to simultaneously administer drug combinations and engage the immune system to fight cancer. Nanoparticles can locate metastases in different organs and deliver medications to them. Using them allows for the effective reduction of tumors with minimal toxicity to healthy tissue. Transition-metal nanoparticles, through Fenton-type or Haber-Weiss-type reactions, generate reactive oxygen species. Through oxidative stress, the particles induce cell death via different pathways. The main limitation of the particles is their toxicity. Certain factors can control toxicity, such as route of administration, size, aggregation state, surface functionalization, or oxidation state. In this review, we attempt to discuss the effects and toxicity of transition-metal nanoparticles.

Nanoparticle therapy for head and neck cancers

PURPOSE OF REVIEW

The current review focuses on the therapeutic use of nanoparticles in head and neck cancer (HNC), highlighting nanoparticles at the most advanced clinical development stages.

RECENT FINDINGS

Literature review covers the three main approaches for therapeutic use of nanoparticles in HNC: first, enhancing radiotherapy effect; second, performing targeted delivery of chemotherapy, immunotherapy, or genome editing molecules; third, photothermal therapy.

SUMMARY

Nanoparticles are spherical nanoscale objects that have application in cancer therapies. Nanoparticles have diverse and often composite structure composition to ensure their function, increase their bioavailability in tumor tissues, and decrease off-target effects, sometimes by means of activating internal or external stimuli. Hafnium oxide nanoparticles are being tested in phase I to III trials for radiotherapy enhancement. Nanoparticle-based delivery of paclitaxel, cisplatin, and of the immune activator CpG-A DNA is being evaluated in phase II trials. No nanoparticle is currently approved for HNC treatment.

Platinum Nanoparticles in Biomedicine: Preparation, Anti-Cancer Activity, and Drug Delivery Vehicles

Cancer is the main cause of morbidity and mortality worldwide, excluding infectious disease. Because of their lack of specificity in chemotherapy agents are used for cancer treatment, these agents have severe systemic side effects, and gradually lose their therapeutic effects because most cancers become multidrug resistant. Platinum nanoparticles (PtNPs) are relatively new agents that are being tested in cancer therapy. This review covers the various methods for the preparation and physicochemical characterization of PtNPs. PtNPs have been shown to possess some intrinsic anticancer activity, probably due to their antioxidant action, which slows tumor growth. Targeting ligands can be attached to functionalized metal PtNPs to improve their tumor targeting ability. PtNPs-based therapeutic systems can enable the controlled release of drugs, to improve the efficiency and reduce the side effects of cancer therapy. Pt-based materials play a key role in clinical research. Thus, the diagnostic and medical industries are exploring the possibility of using PtNPs as a next-generation anticancer therapeutic agent. Although, biologically prepared nanomaterials exhibit high efficacy with low concentrations, several factors still need to be considered for clinical use of PtNPs such as the source of raw materials, stability, solubility, the method of production, biodistribution, accumulation, controlled release, cell-specific targeting, and toxicological issues to human beings. The development of PtNPs as an anticancer agent is one of the most valuable approaches for cancer treatment. The future of PtNPs in biomedical applications holds great promise, especially in the area of disease diagnosis, early detection, cellular and deep tissue imaging, drug/gene delivery, as well as multifunctional therapeutics.

Metallodrugs in cancer nanomedicine

Metal complexes are extensively used for cancer therapy. The multiple variables available for tuning (metal, ligand, and metal-ligand interaction) offer unique opportunities for drug design, and have led to a vast portfolio of metallodrugs that can display a higher diversity of functions and mechanisms of action with respect to pure organic structures. Clinically approved metallodrugs, such as cisplatin, carboplatin and oxaliplatin, are used to treat many types of cancer and play prominent roles in combination regimens, including with immunotherapy. However, metallodrugs generally suffer from poor pharmacokinetics, low levels of target site accumulation, metal-mediated off-target reactivity and development of drug resistance, which can all limit their efficacy and clinical translation. Nanomedicine has arisen as a powerful tool to help overcome these shortcomings. Several nanoformulations have already significantly improved the efficacy and reduced the toxicity of (chemo-)therapeutic drugs, including some promising metallodrug-containing nanomedicines currently in clinical trials. In this critical review, we analyse the opportunities and clinical challenges of metallodrugs, and we assess the advantages and limitations of metallodrug delivery, both from a nanocarrier and from a metal-nano interaction perspective. We describe the latest and most relevant nanomedicine formulations developed for metal complexes, and we discuss how the rational combination of coordination chemistry with nanomedicine technology can assist in promoting the clinical translation of metallodrugs.

The Treatment of Human Colon Xenografts Tumor in Mice with Platinum Nanosphere-5-Fluorouracil-Bovine Albumin

Because 5-fluorouracil (FLU) has side effects in cancer treatment, the use of FLU in therapeutic activities is limited. To overcome this challenge, the use of nano-platforms for its targeting is f great interest in biomedical fields. For this purpose, to reduce the FLU toxicity and improve the its efficacy, platinum nanospheres (PtNS) with anti-cancer properties were used. After producing PtNS by hydrothermal method and loading FLU and bovine albumin (bAL) (PtNS-FLU-bAL), its physicochemical properties were investigated. After evaluating the drug release capability, the toxicity of PtNS-FLU-bAL on HCT-116 cells was assessed by MTT and flow-cytometry. Also, the effects of the nanospheres on tumor status, liver and kidney tissues were evaluated. The results indicate uniform size of the PtNS-FLU-bAL (79±2.04 nm) with spherical shape, loading of more than 50% of the FLU (in the ratio of 2:1 FLU to PtNS-bAL), optimal release of the FLU from the PtNS-FLU-bAL (83.1% in pH = 6), and the high toxicity of the PtNS-FLU-bAL on HCT-116 cells. Also, the toxicity mechanism indicated more apoptosis induction by increasing the expression of TNF-α, Bax, Fas, and Caspase-3 genes for PtNS-FLU-bAL compared to the free FLU. Moreover, the results showed a higher FLU concentration in cancerous tissue and a 1.5-fold reduction in tumor growth by the PtNS-FLU-bAL compared to the free FLU. Overall, the results show that the PtNS-FLU-bAL can enhance the success of colorectal cancer treatment effectively and safely.

Biocompatibility of Platinum Nanoparticles in Brain ex vivo Models in Physiological and Pathological Conditions

Platinum nanoparticles (PtNPs) have unique physico-chemical properties that led to their use in many branches of medicine. Recently, PtNPs gathered growing interest as delivery vectors for drugs, biosensors and as surface coating on chronically implanted biomedical devices for improving electrochemical properties. However, there are contradictory statements about their biocompatibility and impact on target organs such as the brain tissue, where these NPs are finding many applications. Furthermore, many of the reported studies are conducted in homeostasis conditions and, consequently, neglect the impact of the pathologic conditions on the tissue response. To expand our knowledge on the effects of PtNPs on neuronal and glial cells, we investigated the acute effects of monodisperse sodium citrate-coated PtNPs on rat organotypic hippocampal cultures in physiological or neuronal excitotoxic conditions induced by kainic acid (KA). The cellular responses of the PtNPs were evaluated through cytotoxic assays and confocal microscopy analysis. To mimic a pathologic scenario, 7-day organotypic hippocampal cultures were exposed to KA for 24 h. Subsequently, PtNPs were added to each slice. We show that incubation of the slices with PtNPs for 24 h, does not severely impact cell viability in normal conditions, with no significant differences when comparing the dentate gyrus (DG), as well as CA3 and CA1 pyramidal cell layers. Such effects are not exacerbated in KA-treated slices, where the presence of PtNPs does not cause additional neuronal propidium iodide (PI) uptake in CA3 and CA1 pyramidal cell layers. However, PtNPs cause microglial cell activation and morphological alterations in CA3 and DG regions indicating the establishment of an inflammatory reaction. Morphological analysis revealed that microglia acquire activated ameboid morphology with loss of ramifications, as a result of their response to PtNPs contact. Surprisingly, this effect is not increased in pathological conditions. Taken together, these results show that PtNPs cause microglia alterations in short-term studies. Additionally, there is no worsening of the tissue response in a neuropathological induced scenario. This work highlights the need of further research to allow for the safe use of PtNPs. Also, it supports the demand of the development of novel and more biocompatible NPs to be applied in the brain.

Exosome-based drug delivery systems and their therapeutic applications

In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses.

A Hybrid Nanogel to Preserve Lysosome Integrity for Fluorescence Imaging

Fluorescence imaging of lysosomes provides a powerful tool to probe the lysosome physiology in living cells, yet the continuous light exposure inevitably causes lysosome damage and phototoxicity, which remains a formidable challenge. Here the long-term lysosome tracking with minimized photodamage was realized using a multifunctional nanoprobe, a platinum nanoparticle, and a quinacrine co-loaded nanogel. To construct the hybrid nanogel, cisplatin first functioned as cross-linker to withhold all components and then was reduced to a platinum nanoparticle in situ by ethanol. The platinum nanoparticle enabled a long-term quinacrine fluorescence imaging of lysosome by scavenging the light induced reactive oxygen species which could damage lysosomal membranes.

Manganese-based advanced nanoparticles for biomedical applications: future opportunity and challenges

Nanotechnology is the most promising technology to evolve in the last decade. Recent research has shown that transition metal nanoparticles especially manganese (Mn)-based nanoparticles have great potential for various biomedical applications due to their unique fundamental properties. Therefore, globally, scientists are concentrating on the development of various new manganese-based nanoparticles (size and shape dependent) due to their indispensable utilities. Although numerous reports are available regarding the use of manganese nanoparticles, there is no comprehensive review highlighting the recent development of manganese-based nanomaterials and their potential applications in the area of biomedical sciences. The present review article provides an overall survey on the recent advancement of manganese nanomaterials in biomedical nanotechnology and other fields. Further, the future perspectives and challenges are also discussed to explore the wider application of manganese nanoparticles in the near future. Overall, this review presents a fundamental understanding and the role of manganese in various fields, which will attract a wider spectrum of the scientific community.

Ruthenium Complexes: An Alternative to Platinum Drugs in Colorectal Cancer Treatment

Colorectal cancer (CRC) is one of the intimidating causes of death around the world. CRC originated from mutations of tumor suppressor genes, proto-oncogenes and DNA repair genes. Though platinum (Pt)-based anticancer drugs have been widely used in the treatment of cancer, their toxicity and CRC cells' resistance to Pt drugs has piqued interest in the search for alternative metal-based drugs. Ruthenium (Ru)-based compounds displayed promising anticancer activity due to their unique chemical properties. Ru-complexes are reported to exert their anticancer activities in CRC cells by regulating different cell signaling pathways that are either directly or indirectly associated with cell growth, division, proliferation, and migration. Additionally, some Ru-based drug candidates showed higher potency compared to commercially available Pt-based anticancer drugs in CRC cell line models. Meanwhile Ru nanoparticles coupled with photosensitizers or anticancer agents have also shown theranostic potential towards CRC. Ru-nanoformulations improve drug efficacy, targeted drug delivery, immune activation, and biocompatibility, and therefore may be capable of overcoming some of the existing chemotherapeutic limitations. Among the potential Ru-based compounds, only Ru (III)-based drug NKP-1339 has undergone phase-Ib clinical trials in CRC treatment.

Metal-Coordinated Supramolecular Self-Assemblies for Cancer Theranostics

Metal-coordinated supramolecular nanoassemblies have recently attracted extensive attention as materials for cancer theranostics. Owing to their unique physicochemical properties, metal-coordinated supramolecular self-assemblies can bridge the boundary between traditional inorganic and organic materials. By tailoring the structural components of the metal ions and binding ligands, numerous multifunctional theranostic nanomedicines can be constructed. Metal-coordinated supramolecular nanoassemblies can modulate the tumor microenvironment (TME), thus facilitating the development of TME-responsive nanomedicines. More importantly, TME-responsive organic-inorganic hybrid nanomaterials can be constructed in vivo by exploiting the metal-coordinated self-assembly of a variety of functional ligands, which is a promising strategy for enhancing the tumor accumulation of theranostic molecules. In this review, recent advancements in the design and fabrication of metal-coordinated supramolecular nanomedicines for cancer theranostics are highlighted. These supramolecular compounds are classified according to the order in which the coordinated metal ions appear in the periodic table. Furthermore, the prospects and challenges of metal-coordinated supramolecular self-assemblies for both technical advances and clinical translation are discussed. In particular, the superiority of TME-responsive nanomedicines for in vivo coordinated self-assembly is elaborated, with an emphasis on strategies that enhance the accumulation of functional components in tumors for an ideal theranostic outcome.

Endogenous Conjugation of Biomimetic Dinitrosyl Iron Complex with Protein Vehicles for Oral Delivery of Nitric Oxide to Brain and Activation of Hippocampal Neurogenesis

Nitric oxide (NO), a pro-neurogenic and antineuroinflammatory gasotransmitter, features the potential to develop a translational medicine against neuropathological conditions. Despite the extensive efforts made on the controlled delivery of therapeutic NO, however, an orally active NO prodrug for a treatment of chronic neuropathy was not reported yet. Inspired by the natural dinitrosyl iron unit (DNIU) [Fe(NO)₂], in this study, a reversible and dynamic interaction between the biomimetic [(NO)₂Fe(μ-SCH₂CH₂OH)₂Fe(NO)₂] (DNIC-1) and serum albumin (or gastrointestinal mucin) was explored to discover endogenous proteins as a vehicle for an oral delivery of NO to the brain after an oral administration of DNIC-1. On the basis of the in vitro and in vivo study, a rapid binding of DNIC-1 toward gastrointestinal mucin yielding the mucin-bound dinitrosyl iron complex (DNIC) discovers the mucoadhesive nature of DNIC-1. A reversible interconversion between mucin-bound DNIC and DNIC-1 facilitates the mucus-penetrating migration of DNIC-1 shielded in the gastrointestinal tract of the stomach and small intestine. Moreover, the NO-release reactivity of DNIC-1 induces the transient opening of the cellular tight junction and enhances its paracellular permeability across the intestinal epithelial barrier. During circulation in the bloodstream, a stoichiometric binding of DNIC-1 to the serum albumin, as another endogenous protein vehicle, stabilizes the DNIU [Fe(NO)₂] for a subsequent transfer into the brain. With aging mice under a Western diet as a disease model for metabolic syndrome and cognitive impairment, an oral administration of DNIC-1 in a daily manner for 16 weeks activates the hippocampal neurogenesis and ameliorates the impaired cognitive ability. Taken together, these findings disclose the synergy between biomimetic DNIC-1 and endogenous protein vehicles for an oral delivery of therapeutic NO to the brain against chronic neuropathy.

Bioconjugated nanometals and cancer therapy: a pharmaceutical perspective

Conventional cancer chemotherapies are associated with challenges like delivering sub-therapeutic doses to target cells, lack of bioavailability, drug insolubility and nonspecific toxicity to healthy cells. Nanomedicine, an advanced process, can contribute to the development of personalized medicine for diagnosis, therapy and monitoring of cancer. The nanometals enhance drug dissolution and adhesion to targeted tumor surfaces, resulting in rapid onset of effective therapeutic action. Moreover, nanometals can be conjugated with ligands or polymers through a conjugation process, which further leads to enhanced efficiency, target specificity, improved pharmacokinetics and pharmacodynamics of the drug. This review focuses on the applications of conjugated nanometals in cancer therapy, with a special focus on noble and magnetic nanometals.

Influence of Poly(ethylene glycol) Molecular Architecture on Particle Assembly and Ex Vivo Particle-Immune Cell Interactions in Human Blood

Poly(ethylene glycol) (PEG) is widely used in particle assembly to impart biocompatibility and stealth-like properties in vivo for diverse biomedical applications. Previous studies have examined the effect of PEG molecular weight and PEG coating density on the biological fate of various particles; however, there are few studies that detail the fundamental role of PEG molecular architecture in particle engineering and bio-nano interactions. Herein, we engineered PEG particles using a mesoporous silica (MS) templating method and investigated how the PEG building block architecture impacted the physicochemical properties (e.g., surface chemistry and mechanical characteristics) of the PEG particles and subsequently modulated particle-immune cell interactions in human blood. Varying the PEG architecture from 3-arm to 4-arm, 6-arm, and 8-arm generated PEG particles with a denser, stiffer structure, with increasing elastic modulus from 1.5 to 14.9 kPa, inducing an increasing level of immune cell association (from 15% for 3-arm to 45% for 8-arm) with monocytes. In contrast, the precursor PEG particles with the template intact (MS@PEG) were stiffer and generally displayed higher levels of immune cell association but showed the opposite trend-immune cell association decreased with increasing PEG arm numbers. Proteomics analysis demonstrated that the biomolecular corona that formed on the PEG particles minimally influenced particle-immune cell interactions, whereas the MS@PEG particle-cell interactions correlated with the composition of the corona that was abundant in histidine-rich glycoproteins. Our work highlights the role of PEG architecture in the design of stealth PEG-based particles, thus providing a link between the synthetic nature of particles and their biological behavior in blood.

Rollover Cyclometalation vs Nitrogen Coordination in Tetrapyridyl Anticancer Gold(III) Complexes: Effect on Protein Interaction and Toxicity

In this work, a pair of gold(III) complexes derived from the analogous tetrapyridyl ligands H₂biqbpy1 and H₂biqbpy2 was prepared: the rollover, bis-cyclometalated [Au(biqbpy1)Cl ([1]Cl) and its isomer [Au(biqbpy2)Cl ([2]Cl). In [1]⁺, two pyridyl rings coordinate to the metal via a Au-C bond (C^∧N^∧N^∧C coordination) and the two noncoordinated amine bridges of the ligand remain protonated, while in [2]⁺ all four pyridyl rings of the ligand coordinate to the metal via a Au-N bond (N^∧N^∧N^∧N coordination), but both amine bridges are deprotonated. As a result, both complexes are monocationic, which allowed comparison of the sole effect of cyclometalation on the chemistry, protein interaction, and anticancer properties of the gold(III) compounds. Due to their identical monocationic charge and similar molecular shape, both complexes [1]Cl and [2]Cl displaced reference radioligand [³H]dofetilide equally well from cell membranes expressing the K_v11.1 (hERG) potassium channel, and more so than the tetrapyridyl ligands H₂biqbpy1 and H₂biqbpy2. By contrast, cyclometalation rendered [1]Cl coordinatively stable in the presence of biological thiols, while [2]Cl was reduced by a millimolar concentration of glutathione into metastable Au(I) species releasing the free ligand H₂biqbpy2 and TrxR-inhibiting Au⁺ ions. The redox stability of [1]Cl dramatically decreased its thioredoxin reductase (TrxR) inhibition properties, compared to [2]Cl. On the other hand, unlike [2]Cl, [1]Cl aggregated into nanoparticles in FCS-containing medium, which resulted in much more efficient gold cellular uptake. [1]Cl had much more selective anticancer properties than [2]Cl and cisplatin, as it was almost 10 times more cytotoxic to human cancer cells (A549, A431, A375, and MCF7) than to noncancerous cells (MRC5). Mechanistic studies highlight the strikingly different mode of action of the two compounds: while for [1]Cl high gold cellular uptake, nuclear DNA damage, and interaction with hERG may contribute to cell killing, for [2]Cl extracellular reduction released TrxR-inhibiting Au⁺ ions that were taken up in minute amounts in the cytosol, and a toxic tetrapyridyl ligand also capable of binding to hERG. These results demonstrate that bis-cyclometalation is an appealing method to improve the redox stability of Au(III) compounds and to develop gold-based cytotoxic compounds that do not rely on TrxR inhibition to kill cancer cells.

Role of macrophage in nanomedicine-based disease treatment

Macrophages are a major component of the immunoresponse. Diversity and plasticity are two of the hallmarks of macrophages, which allow them to act as proinflammatory, anti-inflammatory, and homeostatic agents. Research has found that cancer and many inflammatory or autoimmune disorders are correlated with activation and tissue infiltration of macrophages. Recent developments in macrophage nanomedicine-based disease treatment are proving to be timely owing to the increasing inadequacy of traditional treatment. Here, we review the role of macrophages in nanomedicine-based disease treatment. First, we present a brief background on macrophages and nanomedicine. Then, we delve into applications of macrophages as a target for disease treatment and delivery systems and summarize the applications of macrophage-derived extracellular vesicles. Finally, we provide an outlook on the clinical utility of macrophages in nanomedicine-based disease treatment.

Lichens-A Potential Source for Nanoparticles Fabrication: A Review on Nanoparticles Biosynthesis and Their Prospective Applications

Green synthesis of nanoparticles (NPs) is a safe, eco-friendly, and relatively inexpensive alternative to conventional routes of NPs production. These methods require natural resources such as cyanobacteria, algae, plants, fungi, lichens, and naturally extracted biomolecules such as pigments, vitamins, polysaccharides, proteins, and enzymes to reduce bulk materials (the target metal salts) into a nanoscale product. Synthesis of nanomaterials (NMs) using lichen extracts is a promising eco-friendly, simple, low-cost biological synthesis process. Lichens are groups of organisms including multiple types of fungi and algae that live in symbiosis. Until now, the fabrication of NPs using lichens has remained largely unexplored, although the role of lichens as natural factories for synthesizing NPs has been reported. Lichens have a potential reducible activity to fabricate different types of NMs, including metal and metal oxide NPs and bimetallic alloys and nanocomposites. These NPs exhibit promising catalytic and antidiabetic, antioxidant, and antimicrobial activities. To the best of our knowledge, this review provides, for the first time, an overview of the main published studies concerning the use of lichen for nanofabrication and the applications of these NMs in different sectors. Moreover, the possible mechanisms of biosynthesis are discussed, together with the various optimization factors influencing the biological synthesis and toxicity of NPs.

Green Synthesis of Platinum and Palladium Nanoparticles Using Peganum harmala L. Seed Alkaloids: Biological and Computational Studies

This study reports a facile and eco-friendly method for the green synthesis of platinum and palladium nanoparticles (Pt NPs and Pd NPs) using Peganum harmala seed alkaloid fraction. The ζ-potential of the synthesized Pt NPs, Pd NPs and Pt–Pd NPs were −11.2 ± 0.5, −9.7 ±1.2, and −12.7 ± 2.1 mV; respectively. Transmission electron microscopy (TEM) revealed the formation of spherical-shaped nanoparticles with smooth margins. The mean diameters of the synthesized Pt NPs, Pd NPs, and Pt–Pd NPs were determined using TEM analysis and were found to be 20.3 ± 1.9, 22.5 ± 5.7, and 33.5 ± 5.4 nm, respectively. The nanoparticles’ bioreduction was confirmed by ultraviolet–visible (UV–vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, and their organic contents were determined by thermal gravimetric analysis (TGA). The Pt–Pd NPs mixture showed more pronounced antioxidant activity of 843.0 ± 60 μM Trolox equivalent (TE)/mg NPs compared to the individual Pt NPs (277.3 ± 13.5 μM TE/mg NPs) and Pd NPs (167.6 ± 4.8 μM TE/mg NPs). Furthermore, the Pt–Pd NPs exhibited significant cytotoxic activities against lung cancer (A549) and breast adenocarcinoma (MCF-7) cells, IC₅₀ of 8.8 and 3.6 µg/mL, respectively; as compared to Pt NPs (IC₅₀ of 10.9 and 6.7 µg/mL, respectively) and Pd NPs (IC₅₀ of 31 and 10.8 µg/mL, respectively and compared to carboplatin (IC₅₀ of 23 and 9.5 µg/mL, respectively). Moreover, molecular docking studies were conducted to explore the possible anticancer and antioxidant mechanisms of the biogenic nanoparticles. Pt NPs, Pd NPs, and their mixture showed inhibitory activity against cysteine proteinase, which supports their high antitumor activity, but moderate antioxidant activity. In conclusion, Pd-Pt NPs mixture prepared using harmala seed alkaloid fraction showed potential as effective antineoplastic agents.

Biological effects of formation of protein corona onto nanoparticles

Administration of nanomaterials based medicinal and drug carrier systems into systemic circulation brings about interaction of blood components e.g. albumin and globulin proteins with these nanosystems. These blood or serum proteins either get loosely attached over these nanocarriers and form soft protein corona or are tightly adsorbed over nanoparticles and hard protein corona formation occurs. Formation of protein corona has significant implications over a wide array of physicochemical and medicinal attributes. Almost all pharmacological, toxicological and carrier characteristics of nanoparticles get prominently touched by the protein corona formation. It is this interaction of nanoparticle protein corona that decides and influences fate of nanomaterials-based systems. In this article, authors reviewed several diverse aspects of protein corona formation and its implications on various possible outcomes in vivo and in vitro. A brief description regarding formation and types of protein corona has been included along with mechanisms and pharmacokinetic, pharmacological behavior and toxicological profiles of nanoparticles has been described. Finally, significance of protein corona in context of its in vivo and in vitro behavior, involvement of biomolecules at nanoparticle plasma interface and other interfaces and effects of protein corona on biocompatibility characteristics have also been touched upon.

Brave new world revisited: Focus on nanomedicine

Nanomedicine is at a crossroads: with relatively few success stories in terms of clinical translation despite more and more research on increasingly sophisticated nanomaterials, it is important to consider whether we are on the right track. Indeed, it is crucial that we address the fact that while considerable efforts are being made to overcome barriers to translation from the bench to the clinic, scientists are still struggling to decipher fundamental aspects of nanomaterial interactions with biological systems. We believe that a key to the successful adoption of nanomedicines in oncology and beyond lies in a deeper understanding of underlying biological processes and in decoding interactions between engineered nanomaterials and biological systems. Here we provide an overview of progress in nanomedicine during the past 5 years.