Innovative synthesis and molecular modeling of actinomycetes-derived silver nanoparticles for biomedical applications

The rising demand for innovative antimicrobial solutions has shifted focus towards silver nanoparticles (AgNPs), especially those produced through eco-friendly methods. This study introduces a novel approach utilizing actinomycetes strains-Streptomyces albus, Micromonospora maris, and Arthrobacter crystallopoietes-to biosynthesize AgNPs with remarkable antibacterial properties. Through molecular characterization, we identified unique features of these nanoparticles, and computational modeling suggested significant ion-ligand interactions with proteins 6REV and 3K07. Our research highlights the promise of these biogenically synthesized nanoparticles in advancing biomedical applications. Actinomycetes were sourced and screened for their ability to produce metallic nanoparticles, revealing that among 35 samples, only six showed this capability. Notably, Streptomyces albus strain smmdk14 (OR685674), Micromonospora maris strain smmdk13 (OR685672), and Arthrobacter crystallopoietes strain smmdk12 (OR685674) were identified as effective silver nanoparticle producers. The synthesized nanoparticles demonstrated potent antibacterial activity against common pathogens including E. coli, Pseudomonas aeruginosa, Klebsiella spp., Enterococcus faecalis, Staphylococcus aureus, and Acinetobacter spp. The data obtained from color change observation, UV-visible spectrophotometry, Zeta potential, FTIR spectroscopy, and transmission electron microscopy (TEM) characterized AgNPs potentiality. The nanoparticles were spherical, with sizes ranging from 6.46 nm to 24.7 nm. Optimization of production conditions, comparison of antimicrobial effects with antibiotics, evaluation of potential toxicity, and assessment of wound-healing capabilities were also conducted. The biosynthesized AgNPs exhibited superior antibacterial properties compared to traditional antibiotics and significantly accelerated wound healing by approximately 66.4 % in fibroblast cell cultures. Additionally, computational analysis predicted interactions between various metal ions and specific amino acid residues in proteins 6REV and 3K07. Overall, this study demonstrates the successful creation of AgNPs with notable antibacterial and wound-healing properties, underscoring their potential for medical applications.

Biotechnological advances in microbial synthesis of gold nanoparticles: Optimizations and applications

This review discusses the eco-friendly and cost-effective biosynthesis of gold nanoparticles (AuNPs) in viable microorganisms, focusing on microbes-mediated AuNP biosynthesis. This process suits agricultural, environmental, and biomedical applications, offering renewable, eco-friendly, non-toxic, sustainable, and time-efficient methods. Microorganisms are increasingly used in green technology, nanotechnology, and RNAi technology, but several microorganisms have not been fully identified and characterized. Bio-nanotechnology offers eco-friendly and sustainable solutions for nanomedicine, with microbe-mediated nanoparticle biosynthesis producing AuNPs with anti-oxidation activity, stability, and biocompatibility. Ultrasmall AuNPs offer rapid distribution, renal clearance, and enhanced permeability in biomedical applications. The review explores nano-size dependent biosynthesis of AuNPs by bacteria, fungi, and viruses revealing their non-toxic, non-genotoxic, and non-oxidative properties on human cells. AuNPs with varying sizes and shapes, from nitrate reductase enzymes, have shown potential as a promising nano-catalyst. The synthesized AuNPs, with negative charge capping molecules, have demonstrated antibacterial activity against drug-resistant Pseudomonas aeruginosa, and Acinetobacter baumannii strains, and were non-toxic to Vero cell lines, indicating potential antibiotic resistance treatments. A green chemical method for the biosynthesis of AuNPs using reducing chloroauric acid and Rhizopus oryzae protein extract has been described, demonstrating excellent stability and strong catalytic activity. AuNPs are eco-friendly, non-toxic, and time-efficient, making them ideal for biomedical applications due to their antioxidant, antidiabetic, and antibacterial properties. In addition to the biomedical application, the review also highlights the role of microbially synthesized AuNPs in sustainable management of plant diseases, and environmental bioremediation.

Assessing anticancer properties of PEGylated platinum nanoparticles on human breast cancer cell lines usingin-vitroassays

This study describes the in-vitro cytotoxic effects of PEG-400 (Polyethylene glycol-400)-capped platinum nanoparticles (PEGylated Pt NPs) on both normal and cancer cell lines. Structural characterization was carried out using x-ray diffraction and Raman spectroscopy with an average crystallite size 5.7 nm, and morphological assessment using Scanning electron microscopy (SEM) revealed the presence of spherical platinum nanoparticles. The results of energy-dispersive x-ray spectroscopy (EDX) showed a higher percentage fraction of platinum content by weight, along with carbon and oxygen, which are expected from the capping agent, confirming the purity of the platinum sample. The dynamic light scattering experiment revealed an average hydrodynamic diameter of 353.6 nm for the PEGylated Pt NPs. The cytotoxicity profile of PEGylated Pt NPs was assessed on a normal cell line (L929) and a breast cancer cell line (MCF-7) using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results revealed an IC50of 79.18 μg ml-1on the cancer cell line and non-toxic behaviour on the normal cell line. In the dual staining apoptosis assay, it was observed that the mortality of cells cultured in conjunction with platinum nanoparticles intensified and the proliferative activity of MCF-7 cells gradually diminished over time in correlation with the increasing concentration of the PEGylated Pt NPs sample. Thein vitroDCFH-DA assay for oxidative stress assessment in nanoparticle-treated cells unveiled the mechanistic background of the anticancer activity of PEGylated platinum nanoparticles as ROS-assisted mitochondrial dysfunction.

Long Noncoding RNA NR_030777 Alleviates Cobalt Nanoparticles-Induced Neurodegenerative Damage by Promoting Autophagosome-Lysosome Fusion

Potential exposure to cobalt nanoparticles (CoNPs) occurs in various fields, including hard alloy industrial production, the increasing use of new energy lithium-ion batteries, and millions of patients with metal-on-metal joint prostheses. Evidence from human, animal, and in vitro experiments suggests a close relationship between CoNPs and neurotoxicity. However, a systematic assessment of central nervous system (CNS) impairment due to CoNPs exposure and the underlying molecular mechanisms is lacking. In this study, we found that CoNPs induced neurodegenerative damage both in vivo and in vitro, including cognitive impairment, β-amyloid deposition and Tau hyperphosphorylation. CoNPs promoted the formation of autophagosomes and impeding autophagosomal-lysosomal fusion in vivo and in vitro, leading to toxic protein accumulation. Moreover, CoNPs exposure reduced the level of transcription factor EB (TFEB) and the abundance of lysosome, causing a blockage in autophagosomal-lysosomal fusion. Interestingly, overexpression of long noncoding RNA NR_030777 mitigated CoNPs-induced neurodegenerative damage in both in vivo and in vitro models. Fluorescence in situ hybridization assay revealed that NR_030777 directly binds and stabilizes TFEB mRNA, alleviating the blockage of autophagosomal-lysosomal fusion and ultimately restoring neurodegeneration induced by CoNPs in vivo and in vitro. In summary, our study demonstrates that autophagic dysfunction is the main toxic mechanism of neurodegeneration upon CoNPs exposure and NR_030777 plays a crucial role in CoNPs-induced autophagic dysfunction. Additionally, the proposed adverse outcome pathway contributes to a better understanding of CNS toxicity assessment of CoNPs.

Assessing inorganic nanoparticle toxicity through omics approaches

In the last two decades, the development of nanotechnology has resulted in inorganic nanoparticles playing crucial roles in key industries, ranging from healthcare to energy technologies. For instance, gold and silver nanoparticles are widely used in rapid COVID-19 and flu tests, titania and zinc oxide nanoparticles are commonly found in cosmetic products, and superparamagnetic iron oxide nanoparticles have been clinically exploited as contrast agents and anti-anemia medicines. As a result, human exposure to nanomaterials is continuously increasing, raising concerns about their potential adverse health effects. Historically, the study of nanoparticle toxicity has largely relied on macroscopic observations obtained in different in vitro and in vivo models, resulting in readouts such as median lethal dose, biodistribution profile, and/or histopathological assessment. In recent years, omics methodologies, including transcriptomics, epigenomics, proteomics, metabolomics, and lipidomics, are increasingly used to characterize the biological interactions of nanomaterials, providing a better and broader understanding of their impact and mechanisms of toxicity. These approaches have been able to identify important genes and gene products that mediate toxicological effects, as well as endogenous functions and pathways dysregulated by nanoparticles. Omics methods improve our understanding of nanoparticle biology, and unravel mechanistic insights into nanomedicine-based therapies. This review aims to provide a deeper understanding and new perspectives of omics approaches to characterize the toxicity and biological interactions of inorganic nanoparticles, and improve the safety of nanoparticle applications.

Advancements in nanomaterials for nanosensors: a comprehensive review

Nanomaterials (NMs) exhibit unique properties that render them highly suitable for developing sensitive and selective nanosensors across various domains. This review aims to provide a comprehensive overview of nanomaterial-based nanosensors, highlighting their applications and the classification of frequently employed NMs to enhance sensitivity and selectivity. The review introduces various classifications of NMs commonly used in nanosensors, such as carbon-based NMs, metal-based NMs, and others, elucidating their exceptional properties, including high thermal and electrical conductivity, large surface area-to-volume ratio and good biocompatibility. A thorough examination of literature sources was conducted to gather information on NMs-based nanosensors' characteristics, properties, and fabrication methods and their application in diverse sectors such as healthcare, environmental monitoring, industrial processes, and security. Additionally, advanced applications incorporating machine learning techniques were analyzed to enhance the sensor's performance. This review advances the understanding and development of nanosensor technologies by providing insights into fabrication techniques, characterization methods, applications, and future outlook. Key challenges such as robustness, biocompatibility, and scalable manufacturing are also discussed, offering avenues for future research and development in this field.

An Outlook on Platinum-Based Active Ingredients for Dermatologic and Skincare Applications

Platinum-based materials exhibit a broad spectrum of biological activities, including antioxidant, anti-inflammatory, antimicrobial, and pro-collagen synthesis properties, making them particularly useful for various biomedical applications. This review summarizes the biological effects and therapeutic potential of platinum-based active ingredients in dermatological and skincare applications. We discuss their synthesis methods and their antioxidant, anti-inflammatory, antimicrobial, and collagen synthesis properties, which play essential roles in treating skin conditions including psoriasis and acne, as well as enhancing skin aesthetics in anti-aging products. Safety and sustainability concerns, including the need for green synthesis and comprehensive toxicological assessments to ensure safe topical applications, are also discussed. By providing an up-to-date overview of current research, we aim to highlight both the potential and the current challenges of platinum-based active ingredients in advancing dermatology and skincare solutions.

Recent Advances in Photodynamic Therapy: Metal-Based Nanoparticles as Tools to Improve Cancer Therapy

Cancer remains a significant global health challenge, with traditional therapies like surgery, chemotherapy, and radiation often accompanied by systemic toxicity and damage to healthy tissues. Despite progress in treatment, these approaches have limitations such as non-specific targeting, systemic toxicity, and resistance development in cancer cells. In recent years, nanotechnology has emerged as a revolutionary frontier in cancer therapy, offering potential solutions to these challenges. Nanoparticles, due to their unique physical and chemical properties, can carry therapeutic payloads, navigate biological barriers, and selectively target cancer cells. Metal-based nanoparticles, in particular, offer unique properties suitable for various therapeutic applications. Recent advancements have focused on the integration of metal-based nanoparticles to enhance the efficacy and precision of photodynamic therapy. Integrating nanotechnology into cancer therapy represents a paradigm shift, enabling the development of strategies with enhanced specificity and reduced off-target effects. This review aims to provide a comprehensive understanding of the pivotal role of metal-based nanoparticles in photodynamic therapy. We explore the mechanisms, biocompatibility, and applications of metal-based nanoparticles in photodynamic therapy, highlighting the challenges and the limitations in their use, as well as the combining of metal-based nanoparticles/photodynamic therapy with other strategies as a synergistic therapeutic approach for cancer treatment.

A review on gold nanoparticles as an innovative therapeutic cue in bone tissue engineering: Prospects and future clinical applications

Bone damage is a complex orthopedic problem primarily caused by trauma, cancer, or bacterial infection of bone tissue. Clinical care management for bone damage remains a significant clinical challenge and there is a growing need for more advanced bone therapy options. Nanotechnology has been widely explored in the field of orthopedic therapy for the treatment of a severe bone disease. Among nanomaterials, gold nanoparticles (GNPs) along with other biomaterials are emerging as a new paradigm for treatment with excellent potential for bone tissue engineering and regenerative medicine applications. In recent years, a great deal of research has focused on demonstrating the potential for GNPs to provide for enhancement of osteogenesis, reduction of osteoclastogenesis/osteomyelitis, and treatment of bone cancer. This review details the latest understandings in regards to GNPs based therapeutic systems, mechanisms, and the applications of GNPs against various bone disorders. The present review aims to summarize i) the mechanisms of GNPs in bone tissue remodeling, ii) preparation methods of GNPs, and iii) functionalization of GNPs and its decoration on biomaterials as a delivery vehicle in a specific bone tissue engineering for future clinical application.

Supported of gold nanoparticles on carboxymethyl lignin modified magnetic nanoparticles as an efficient catalyst for reduction of nitroarenes and treatment of human melanoma

This article represents the synthesis and characterizations of Au NPs immobilized and carboxymethyl lignin (CML) modified Fe3O4 nanoparticles (Fe3O4@CML/Au NPs) following a bio-inspired protocol without the participation of any toxic and harmful reductant or stabilizers. Following various physicochemical methodologies, such as FT-IR, FE-SEM, TEM, EDX, XRD, VSM, and ICP-OES, the textural characteristics and different structural aspects were evaluated. The Fe3O4@CML/Au NPs nanocomposite was subsequently explored towards the catalytic reduction of diverse aromatic nitro functions using green conditions. An excellent yield were achieved within very short reaction time. Nine recycling runs of the nanocatalyst were completed without a discernible loss of catalytic activity, thanks to its easy magnetic recovery. The DPPH assay was carried out to examine the antioxidant effectiveness. The Fe3O4@CML/Au NPs nanocomposite inhibited half of the DPPH in a 250 μg/mL solution. To measure the anti-human melanoma efficacy of Fe3O4@CML/Au NPs nanocomposite, MTT assay was applied on HT144, MUM2C, IPC-298 and SKMEL24 cell lines. Fe3O4@CML/Au NPs nanocomposite had high anti-human melanoma efficacy on above tumor cells. The best finding of anti-human melanoma properties of Fe3O4@CML/Au NPs nanocomposite was seen in the case of the SKMEL24 cell line. The IC50 of Fe3O4@CML/Au NPs nanocomposite was 137, 145, 185, and 125 μg/mL against HT144, MUM2C, IPC-298 and SKMEL24 cells, respectively. This research exhibited remarkable anti-human melanoma and antioxidant efficacies of Fe3O4@CML/Au NPs nanocomposite in the in vitro condition.

Fabrication of CuNPs Using Schiff Base Ligand and Their Catalytic Reduction of Pharmaceutical Drugs, Fluorescence Selective Detection of Cd2+, Antimicrobial, and Antioxidant Activities

Here, we have approached the synthesis of copper nanoparticles (CuNPs) Schiff base (5-trifluoromethoxy-2-(((2chloro-5-(methyl)phenyl)imino)methyl)phenol)). The synthesized CuNPs were characterized by UV-vis spectroscopy, PL, FTIR, powder XRD, and TEM analysis. From the UV-vis absorption spectroscopy, an absorption peak was observed at 585 nm. As a result of the powder XRD and TEM studies, spherical particle sizes ranged between 4 and 10 nm. FT-IR analysis confirmed the presence of functional groups ‒OH, C=C, -C=N-, and C‒H triggers the synthesis of CuNPs. Further, the catalytic property of the CuNPs were revealed by the degradation of pharmaceutical drugs such as Capecitabine (CAP) and Ciprofloxacin (CIP) in 90 min of reaction time in the presence of NaBH4. The reaction kinetics followed pseudo-first-order with k-values (rate constant) 0.248 min-1 and 0.307 min-1. In addition, the synthesized CuNPs have exhibited selective sensing detection of Cd2+ metal ions in different range of concentration (10-100 µM) by spectrofluorometrically with the limit of detection (LOD) is 0.0284 nM and limit of quantification (LOQ) is 0.0586 nM. The CuNPs revealed significant antioxidant activities against DPPH as a common free radical at 50 µg/mL with 71.24% of scavenging activity. The maximum antimicrobial potential and zone of inhibition of P. Aeruginosa is 17.25±0.8 mm and A. niger is 12.1 mm by using CuNPs.

Determination of Aminophylline in Human Serum Using Hydrogel Microspheres for Coupled Surface-Enhanced Raman Spectroscopy (SERS) and Solid-Phase Extraction

Aminophylline (AMP) is a bronchodilator. The therapeutic and toxic doses are very close. Therefore, therapeutic drug monitoring (TDM) of AMP is essential in clinical practice. Microgels were synthesized by free radical precipitation polymerization. Silver@poly(N-isopropyl acrylamide) (Ag@PNIPAM) hybrid microgels were obtained by loading silver (Ag) nanoparticles into the three-dimensional network of the microgels by in situ reduction. The microgel is a three-dimensional reticular structure with tunable pore size, large specific surface area, and good biocompatibility, which can be used as a sorbent for solid-phase extraction (SPE) of target molecules in complex matrices and as a surface-enhanced Raman spectroscopy (SERS) substrate. We optimized the conditions affecting SERS enhancement, such as silver nitrate (AgNO3) concentration and SPE time, according to the SERS strategy of Ag@PNIPAM hybrid microgels to achieve label-free TDM for trace AMP in human serum. The results showed good linearity between the logarithmic concentration of AMP and its SERS intensity in the range of 1-1.1 × 102 µg/mL, with a correlation coefficient (R2) of 0.9947 and a low detection limit of 0.61 µg/mL. The assay accuracy was demonstrated by spiking experiments, with recoveries ranging from 93.0 to 101.8%. The method is rapid, sensitive, reproducible, requires simple sample pretreatment, and has good potential for use in clinical treatment drug monitoring.

Green synthesis of silver nanoparticles employing hamdard joshanda extract: putative antimicrobial potential against gram positive and gram negative bacteria

The bio-mediated synthesis of nanoparticles offers a sustainable and eco-friendly approach. In the present study, silver nanoparticles (AgNPs) were synthesized using Joshanda extract, a commercially available herbal formulation derived from a traditional medicinal plant, as a reducing and stabilizing agent. The as-synthesized AgNPs were characterized using UV-Vis spectroscopy, dynamic light scattering (DLS), X-ray Diffraction (XRD) study, and Fourier-transform infrared (FTIR) analysis. UV-Vis spectroscopy exhibited a prominent absorption peak at 430 nm, confirming the formation of AgNPs. DLS analysis revealed the size distribution of the nanoparticles, ranging from 80 to 100 nm, and zeta potential measurements indicated a surface charge of - 14.4 mV. The XRD analysis provide evidence for the presence of a face-centered cubic structure within the silver nanoparticles. FTIR analysis further elucidated the interaction of bioactive compounds from the Joshanda extract with the AgNPs' surface. Strong peaks at 765-829 cm-1 indicated C-Cl stretching vibrations of alkyl halides, while the stretching of alkenes C=C was observed at 1641 cm-1. Moreover, the presence of alcohols and phenol (OH) groups was identified at 3448 cm-1, suggesting their involvement in nanoparticle stabilization. The antimicrobial potential of the synthesized AgNPs was evaluated against both gram-negative Pseudomonas aeruginosa and gram-positive Streptococcus mutans using zone of inhibition assays. The AgNPs exhibited remarkable inhibitory effects against both types of bacteria. Additionally, AgNPs-treated groups demonstrated a significant increase in reactive oxygen species (ROS) levels, indicating potential of as-synthesized AgNPs in disruption of the target microbial membranes. Furthermore, the as-synthesized AgNPs exhibited notable anti-biofilm properties by effectively hindering the development of mature biofilms. This study highlights the efficient green synthesis of AgNPs using Joshanda extract and also provides insights into their physico-chemical properties of as-synthesized nanoparticles. The demonstrated antimicrobial activity against both gram-negative and gram-positive bacteria, along with biofilm inhibition potential, underscores the promising applications of the as-synthesized AgNPs in the field of biomedical and environmental sciences. The study bridges traditional knowledge with contemporary nanotechnology, offering a novel avenue for the development of eco-friendly antimicrobial agents.

Amino acid-mediated amorphous copper sulphide with enhanced photothermal conversion efficiency for antibacterial application

Pathogenic bacteria in daily life, such as Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), often seriously affect human life and health. The extensive use of antibiotics has led to the emergence of drug-resistant bacteria, so it is urgent to develop efficient and non-drug-resistant sterilization methods. Here, we use small-molecule cysteine (Cys) as an auxiliary agent to synthesize spherical porous amorphous CuS-Cysteine (CuS-C) nanoparticles, which have good dispersion in aqueous solutions, and explore the reaction mechanism of Cys-induced CuS synthesis. The synthesized composite nanomaterials have strong near-infrared light absorption ability and efficient photothermal conversion ability and can effectively ablate pathogenic bacteria under the irradiation of an 808 nm laser. In addition, antibacterial experiments showed that CuS-C composites had no bactericidal effect without near-infrared light, but they had a good photothermal bactericidal effect on S. aureus and E. coli under radiation conditions. Considering the simple synthesis process, strong photothermal conversion ability, low cost, and suitability for large-scale production, CuS-C nanocomposites, as a promising antibacterial material, will provide a feasible scheme for the treatment of drug-resistant pathogens.

Rapid Synthesis of Noble Metal Colloids by Plasma-Liquid Interactions

The interactions between plasma and liquids cause complex physical and chemical reactions at the gas-liquid contact surface, producing numerous chemically active particles that can rapidly reduce noble metal ions. This study uses atmospheric-pressure surface dielectric barrier discharge (DBD) plasma to treat ethanol aqueous solutions containing noble metal precursors, and stable gold, platinum, and palladium colloids are obtained within a few minutes. To evaluate the mechanism of the reduction of noble metal precursors by atmospheric-pressure surface DBD plasma, the corresponding metal colloids are prepared first by activating an ethanol aqueous solution with plasma and then adding noble metal precursors. It is found that the long-lived active species hydrogen peroxide (H2O2) plays a dominant role in the synthesis process, which has distinct effects on different metal ions. When HAuCl4 and H2PdCl4 are used as precursors, H2O2 acts as a reducing agent, and AuCl4- and PdCl42- ions can be reduced to metallic Au and Pd. However, when AgNO3 is the precursor, H2O2 acts as an oxidising agent, and Ag+ ions cannot be reduced to obtain metal colloids because metallic Ag can be dissolved in H2O2 under acidic conditions. A similar phenomenon was also observed for the preparation of Pd colloid-PA with a plasma-activated ethanol aqueous solution using Pd(NO3)2 as a Pd precursor.

Emerging Trends in Zinc Ferrite Nanoparticles for Biomedical and Environmental Applications

Over the last few decades, the application of nanoparticles (NPs) gained immense attention towards environmental and biomedical applications. NPs are ultra-small particles having size ranges from 1 to 100 nm. NPs loaded with therapeutic or imaging compounds have proved a versatile approach towards healthcare improvements. Among various inorganic NPs, zinc ferrite (ZnFe2O4) NPs are considered as non-toxic and having an improved drug delivery characteristics . Several studies have reported broader applications of ZnFe2O4 NPs for treating carcinoma and various infectious diseases. Additionally, these NPs are beneficial for reducing organic and inorganic environmental pollutants. This review discusses about various methods to fabricate ZnFe2O4 NPs and their physicochemical properties. Further, their biomedical and environmental applications have also been explored comprehensively.

Effects of Spherical and Rod-like Gold Nanoparticles on the Reactivity of Human Peripheral Blood Leukocytes

Gold nanoparticles (GNPs) are widely used in the technological and biomedical industries, which is a major driver of research on these nanoparticles. The main goal of this study was to determine the influence of GNPs (at 20, 100, and 200 μg/mL concentrations) on the reactivity of human peripheral blood leukocytes. Flow cytometry was used to evaluate the respiratory burst activity and pyroptosis in monocytes and granulocytes following incubation with GNPs for 30 and 60 min. Furthermore, the concentration of interleukin-1β (IL-1β) in human blood samples was assessed using enzyme-linked immunosorbent assay (ELISA) after their incubation with GNPs for 24 h. Under the conditions tested in the study, the GNPs did not significantly affect the production of reactive oxygen species in the granulocytes and monocytes that were not stimulated using phorbol 12-myristate 13-acetate (PMA) in comparison to the samples exposed to PMA (p < 0.05). Compared to the control sample, the greatest significant increase in the mean fluorescence intensity of the granulocytes occurred in the samples incubated with CGNPs = 100 and 200 µg/mL for tinc = 30 and 60 min (p < 0.05). From our results, we conclude that the physicochemical properties of the nanoparticles, chemical composition, and the type of nanoparticles used in the unit, along with the unit and incubation time, influence the induced toxicity.

Copper-Based Single-Atom Nanozyme System Mimicking Platelet Cells for Enhancing the Outcome of Radioimmunotherapy

Background

Radiotherapy is an indispensable part of the multidisciplinary treatment of breast cancer (BC). Due to the potential for serious side effects from ionizing radiation in the treatment of breast cancer, which can adversely affect the patient's quality of life, the radiation dose is often limited. This limitation can result in an incomplete eradication of tumors.

Methods

In this study, biomimetic copper single-atom catalysts (platelet cell membrane camouflaging, PC) were synthesized with the aim of improving the therapeutic outcomes of radiotherapy for BC. Following guidance to the tumor site facilitated by the platelet cell membrane coating, PC releases a copper single-atom nanozyme (SAzyme). This SAzyme enhances therapeutic effects by generating reactive oxygen species from H2O2 and concurrently inhibiting the self-repair mechanisms of cancer cells through the consumption of intracellular glutathione (GSH) within the tumor microenvironment. PC-augmented radiotherapy induces immunogenic cell death, which triggers an immune response to eradicate tumors.

Results

With the excellent biocompatibility, PC exhibited precise tumor-targeting capabilities. Furthermore, when employed in conjunction with radiotherapy, PC showed impressive tumor elimination results through immunological activation. Remarkably, the tumor suppression rate achieved with PC-enhanced radiotherapy reached an impressive 93.6%.

Conclusion

Therefore, PC presents an innovative approach for designing radiosensitizers with tumor-specific targeting capabilities, aiming to enhance the therapeutic impact of radiotherapy on BC.

DNA nanostructures as biomolecular scaffolds for antigen display

Nanoparticle-based vaccines offer a multivalent approach for antigen display, efficiently activating T and B cells in the lymph nodes. Among various nanoparticle design strategies, DNA nanotechnology offers an innovative alternative platform, featuring high modularity, spatial addressing, nanoscale regulation, high functional group density, and lower self-antigenicity. This review delves into the potential of DNA nanostructures as biomolecular scaffolds for antigen display, addressing: (1) immunological mechanisms behind nanovaccines and commonly used nanoparticles in their design, (2) techniques for characterizing protein NP-antigen complexes, (3) advancements in DNA nanotechnology and DNA-protein assembly approach, (4) strategies for precise antigen presentation on DNA scaffolds, and (5) current applications and future possibilities of DNA scaffolds in antigen display. This analysis aims to highlight the transformative potential of DNA nanoscaffolds in immunology and vaccinology. This article is categorized under: Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Biology-Inspired Nanomaterials > Protein and Virus-Based Structures.

Structural and optical properties of the Agn-tyrosine complexes (n = 3-12): a density functional theory study

We study the optical properties of Agn (n = 3-12) neutral clusters and their coordination with a tyrosine (Tyr) molecule. A global search strategy coupled with density functional theory (DFT) computations explored the potential energy surface. Adsorption energy calculations predicted that Tyr coordination stabilizes the metal clusters, favouring the Agn-Tyr complexes with an even number of silver atoms. For the Agn low-lying isomers, the general shape and the major transitions of the calculated time dependent-DFT (TD-DFT) absorption spectra align with those of previous reports measured in an argon environment. We use the analysis of non-covalent interactions to identify the specific interactions between each silver cluster and functional groups of Tyr. The TD-DFT absorption spectra for the Agn-Tyr complexes showed that Tyr significantly modifies the optical properties of the coordinated silver clusters and affects the smaller systems to a greater extent. The optical absorption results of the bare Agn clusters and the Agn-Tyr complexes are compared and discussed in detail.

Multifunctional mesoporous silica nanoparticles for biomedical applications

Mesoporous silica nanoparticles (MSNs) are recognized as a prime example of nanotechnology applied in the biomedical field, due to their easily tunable structure and composition, diverse surface functionalization properties, and excellent biocompatibility. Over the past two decades, researchers have developed a wide variety of MSNs-based nanoplatforms through careful design and controlled preparation techniques, demonstrating their adaptability to various biomedical application scenarios. With the continuous breakthroughs of MSNs in the fields of biosensing, disease diagnosis and treatment, tissue engineering, etc., MSNs are gradually moving from basic research to clinical trials. In this review, we provide a detailed summary of MSNs in the biomedical field, beginning with a comprehensive overview of their development history. We then discuss the types of MSNs-based nanostructured architectures, as well as the classification of MSNs-based nanocomposites according to the elements existed in various inorganic functional components. Subsequently, we summarize the primary purposes of surface-functionalized modifications of MSNs. In the following, we discuss the biomedical applications of MSNs, and highlight the MSNs-based targeted therapeutic modalities currently developed. Given the importance of clinical translation, we also summarize the progress of MSNs in clinical trials. Finally, we take a perspective on the future direction and remaining challenges of MSNs in the biomedical field.

Metal-Phenolic Networks for Chronic Wounds Therapy

Chronic wounds are recalcitrant complications of a variety of diseases, with pathologic features including bacterial infection, persistent inflammation, and proliferation of reactive oxygen species (ROS) levels in the wound microenvironment. Currently, the use of antimicrobial drugs, debridement, hyperbaric oxygen therapy, and other methods in clinical for chronic wound treatment is prone to problems such as bacterial resistance, wound expansion, and even exacerbation. In recent years, researchers have proposed many novel materials for the treatment of chronic wounds targeting the disease characteristics, among which metal-phenolic networks (MPNs) are supramolecular network structures that utilize multivalent metal ions and natural polyphenols complexed through ligand bonds. They have a flexible and versatile combination of structural forms and a variety of formations (nanoparticles, coatings, hydrogels, etc.) that can be constructed. Functionally, MPNs combine the chemocatalytic and bactericidal properties of metal ions as well as the anti-inflammatory and antioxidant properties of polyphenol compounds. Together with the excellent properties of rapid synthesis and negligible cytotoxicity, MPNs have attracted researchers' great attention in biomedical fields such as anti-tumor, anti-bacterial, and anti-inflammatory. This paper will focus on the composition of MPNs, the mechanisms of MPNs for the treatment of chronic wounds, and the application of MPNs in novel chronic wound therapies.

One-pot green bio-assisted synthesis of highly active catalytic palladium nanoparticles in porcine gastric mucin for environmental applications

In this work, palladium nanoparticles were synthesized using one-pot synthesis utilizing porcine gastric mucin glycoproteins as reducing and capping agents. It is shown that the particles exhibited noticeable catalytic activity through both nitrophenol reduction and Suzuki-Miyaura coupling reactions. The catalytic performance was demonstrated with exceptionally high product yield, a fast reaction rate, and low catalyst use. The palladium-mucin composites obtained could be used in particle solution and as hydrogel catalysts to increase their reusability for at least ten reaction cycles with minimum loss in their catalytic effectiveness.

Current Trends on the Effects of Metal-Based Nanoparticles on Microbial Ecology

The growing field of nanotechnology and its many applications have led to the irregular release of nanoparticles (NPs), with unintended effects on the environment and continued contamination of water bodies. Metallic NPs are used more frequently in extreme environmental conditions due to their higher efficiency, which attracts more attention in various applications. Due to improper pre-treatment of biosolids, inefficient wastewater treatment practices, and other unregulated agricultural practices continue to contaminate the environment. In particular, the uncontrolled use of NPs in various industrial applications has led to damage to the microbial flora and caused irreplaceable damage to animals and plants. This study focuses on the effect of different doses, types, and compositions of NP on the ecosystem. The review also mentions the impact of various metallic NPs on microbial ecology, their interactions with microorganisms, ecotoxicity studies, and dosage evaluation of the NPs, mainly focused on the review article. However, further research is still needed to understand the complexity of interactions between NPs and microbes in soil and aquatic ecosystems.

Fabrication of silver nanoparticles immobilized on magnetic lignosulfonate: Evaluation of its catalytic activity in the N-acetylation reactions and investigation of its anti-cutaneous squamous cell carcinoma effects

Due to the non-optimal response of most types of cancer to various treatment methods and their rapid progress, research continues in the field of producing drugs with less toxicity and greater efficiency. There are many nanocomposites with diverse biological activities that include part of anticancer drugs in new pharmacological science. The present investigation describes a green procedure for the in situ support of Ag nanoparticles (NPs) over sodium lignosulfonate (NaLS) modified magnetic nanoparticles (Fe3O4@NaLS/Ag) and its subsequent biological and chemical performance. FT-IR, TEM, FE-SEM, EDS, ICP, VSM and XRD techniques were used to characterize the synthesized Fe3O4@NaLS/Ag. The catalytic efficacy of the desired composite was applied in the N-acetylation of various amines in the presence of Ac2O under solvent-free conditions. The Fe3O4@NaLS/Ag catalyst was recovered by an external magnet and reused for nine runs without a significant decrease in the activity. The cytotoxic and anti-cutaneous squamous cell carcinoma potentials of biologically synthesized Fe3O4@NaLS/Ag nanocomposite against PM1 and MET1 cells were determined. The anti-cutaneous squamous cell carcinoma properties of the Fe3O4@NaLS/Ag nanocomposite could significantly remove PM1 and MET1 cells. The IC50 of Fe3O4@NaLS/Ag nanocomposite was 288 and 270 μg/mL against PM1 and MET1 cells, respectively. Also, Fe3O4@NaLS/Ag nanocomposite presented a high antioxidant potential according to the IC50 value. According to the above results, the recent nanocomposite can be used in treating cutaneous squamous cell carcinoma after doing clinical trial studies.

Biosynthesis of copper oxide nanoparticles using Caesalpinia sappan extract: In vitro evaluation of antifungal and antibiofilm activities against Candida albicans

Synthesis of nanoparticles using natural organic substances has attracted more attention due to avoiding inorganic toxicity. This work aimed to synthesize copper oxide nanoparticles (CuONPs) using Caesalpinia sappan heartwood extract as a reducing agent. The effects of pH of synthesis reaction were investigated. The obtained CuONPs were characterized using UV-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Their particle size, size distribution, and zeta potential were determined using photon correlation spectrophotometry. Candida albicans is a major cause of chronic fungal infections due to its biofilms leading to severe drug resistance problems. In this study, in vitro antifungal and antibiofilm activities as well as killing kinetics of the synthesized CuONPs against C. albicans were investigated. Additionally, fungal biofilm was observed by using confocal laser scanning microscopy. The results showed that the pH of the synthesis reaction played an important role in the physicochemical properties and antifungal activities of the obtained CuONPs. CuONPs synthesized at pH 10 and 12 showed the relatively small and narrow size distribution with high negative zeta potential and time-dependent killing kinetics. Confocal laser scanning microscopy confirms obvious fungal biofilm reduction and increased fungal cell death after exposure to CuONPs. These findings suggest the optimal pH of CuONPs synthesis using C. sappan extract as a reducing agent. The results on antifungal and antibiofilm activities indicate that the obtained CuONPs can be a promising agent for treating fungal infection.

Hybrid Nanoparticle/DNAzyme Electrochemical Biosensor for the Detection of Divalent Heavy Metal Ions and Cr3

A hybrid noble nanoparticle/DNAzyme electrochemical biosensor is proposed for the detection of Pb2+, Cd2+, and Cr3+. The sensor takes advantage of a well-studied material that is known for its selective interaction with heavy metal ions (i.e., DNAzymes), which is combined with metallic nanoparticles. The double-helix structure of DNAzymes is known to dissociate into smaller fragments in the presence of specific heavy metal ions; this results in a measurable change in device resistance due to the collapse of conductive inter-nanoparticle DNAzyme bridging. The paper discusses the effect of DNAzyme anchoring groups (i.e., thiol and amino functionalization groups) on device performance and reports on the successful detection of all three target ions in concentrations that are well below their maximum permitted levels in tap water. While the use of DNAzymes for the detection of lead in particular and, to some extent, cadmium has been studied extensively, this is one of the few reports on the successful detection of chromium (III) via a sensor incorporating DNAzymes. The sensor showed great potential for its future integration in autonomous and remote sensing systems due to its low power characteristics, simple and cost-effective fabrication, and easy automation and measurement.

Pd nanoparticles decorated ultrathin 2D metal-organic framework nanosheets with enhanced peroxidase-mimic activity and colorimetric assay of glucose

In addition to size, shape and morphology, enzyme-mimetic property could be efficiently regulated by controlling composition, forming complexes or hybrids, and surface modification. Herein, Pd nanoparticles with an average diameter of 2.52 nm were decorated on ultrathin 2D copper(ii)-porphyrin derived metal-organic framework (MOF) nanosheets by a simple reduction method for catalytic activity regulation. In comparison with other nanozymes, the as-synthesized Pd modified 2D MOF hybrid nanosheets (Pd@Cu-TCPP(Fe)) presented excellent peroxidase-mimic activity, exhibiting an even superior catalytic ability towards H2O2 with a Michaelis-Menten constant as low as 2.33 mM. Based on a cascade reaction between glucose oxidase and Pd@Cu-TCPP(Fe), a colorimetric method for the detection of glucose was established and validated with a wide linear range (0.2-8.0 mM), good recovery (89.5-94.2%) and nice reproducibility (3.65%). All these features guaranteed its excellent ability for glucose determination in human cerebrospinal fluids. This study could offer a valuable reference for constructing novel optical biosensors.

Exploring the Biomedical Applications of Biosynthesized Silver Nanoparticles Using Perilla frutescens Flavonoid Extract: Antibacterial, Antioxidant, and Cell Toxicity Properties against Colon Cancer Cells

The present study reports the biomimetic synthesis of silver nanoparticles (AgNPs) using a simple, cost effective and eco-friendly method. In this method, the flavonoid extract of Perilla frutescens (PFFE) was used as a bioreduction agent for the reduction of metallic silver into nanosilver, called P. frutescens flavonoid extract silver nanoparticles (PFFE-AgNPs). The Ultraviolet-Visible (UV-Vis) spectrum showed a characteristic absorption peak at 440 nm that confirmed the synthesis of PFFE-AgNPs. A Fourier transform infrared spectroscopic (FTIR) analysis of the PFFE-AgNPs revealed that flavonoids are involved in the bioreduction and capping processes. X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns confirmed the face-centered cubic (FCC) crystal structure of PFFE-AgNPs. A transmission electron microscopic (TEM) analysis indicated that the synthesized PFFE-AgNPs are 20 to 70 nm in size with spherical morphology and without any aggregation. Dynamic light scattering (DLS) studies showed that the average hydrodynamic size was 44 nm. A polydispersity index (PDI) of 0.321 denotes the monodispersed nature of PFFE-AgNPs. Further, a highly negative surface charge or zeta potential value (-30 mV) indicates the repulsion, non-aggregation, and stability of PFFE-AgNPs. PFFE-AgNPs showed cytotoxic effects against cancer cell lines, including human colon carcinoma (COLO205) and mouse melanoma (B16F10), with IC50 concentrations of 59.57 and 69.33 μg/mL, respectively. PFFE-AgNPs showed a significant inhibition of both Gram-positive (Listeria monocytogens and Enterococcus faecalis) and Gram-negative (Salmonella typhi and Acinetobacter baumannii) bacteria pathogens. PFFE-AgNPs exhibited in vitro antioxidant activity by quenching 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) free radicals with IC50 values of 72.81 and 92.48 µg/mL, respectively. In this study, we also explained the plausible mechanisms of the biosynthesis, anticancer, and antibacterial effects of PFFE-AgNPs. Overall, these findings suggest that PFFE-AgNPs have potential as a multi-functional nanomaterial for biomedical applications, particularly in cancer therapy and infection control. However, it is important to note that further research is needed to determine the safety and efficacy of these nanoparticles in vivo, as well as to explore their potential in other areas of medicine.

Down-Regulation of HSP by Pd-Cu Nanozymes for NIR Light Triggered Mild-Temperature Photothermal Therapy Against Wound Bacterial Infection: In vitro and in vivo Assessments

Purpose

We aimed to develop an oxidative-stress-activated palladium-copper nanozyme to reduce bacterial's heat sensitivity by down-regulating heat shock proteins to overcome the shortcomings of conventional photothermal antimicrobial therapy and achieve mild photothermal bactericidal efficacy.

Methods

We first synthesized palladium-copper nanozymes (PC-NPs) by hydration and used transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy to demonstrate their successful preparation. Their photothermal therapy (PTT) and chemo-dynamic therapy (CDT) activities were then determined by a series of photothermal performance tests and peroxidase-like performance tests, and the destruction of heat shock proteins by reactive oxygen species (ROS) was verified at the protein level by Western Blotting tests, providing a basis for the effective bacteria-killing by the mild-temperature photothermal treatment subsequently applied. We also validated this promising programmed and controlled antimicrobial treatment with palladium-copper nanozymes by in vivo/in vitro antimicrobial assays. A hemolysis assay, MTT cytotoxicity test and histopathological analysis were also performed to assess the in vivo safety of PC-NPs.

Results

In the micro-acidic environment of bacterial infection, PC-NPs showed peroxidase-like activity that broke down the H2O2 at the wound into hydroxyl radicals and down-regulated bacterial heat shock proteins. The application of PC-NPs increased bacteria's sensitivity to subsequent photothermal treatment, enabling the elimination of bacteria via mild photothermal treatment.

Conclusion

The programmed synergistic catalytic enhancement of CDT and mild photothermal therapy achieves the most efficient killing of bacteria and their biofilms, which brings future thinking in the relationship between heat shock proteins and oxidative stress damage in bacteria.

Antioxidant and Prooxidant Nanozymes: From Cellular Redox Regulation to Next-Generation Therapeutics

Nanozymes, nanomaterials with enzyme-mimicking activity, have attracted tremendous interest in recent years owing to their ability to replace natural enzymes in various biomedical applications, such as biosensing, therapeutics, drug delivery, and bioimaging. In particular, the nanozymes capable of regulating the cellular redox status by mimicking the antioxidant enzymes in mammalian cells are of great therapeutic significance in oxidative-stress-mediated disorders. As the distinction of physiological oxidative stress (oxidative eustress) and pathological oxidative stress (oxidative distress) occurs at a fine borderline, it is a great challenge to design nanozymes that can differentially sense the two extremes in cells, tissues and organs and mediate appropriate redox chemical reactions. In this Review, we summarize the advances in the development of redox-active nanozymes and their biomedical applications. We primarily highlight the therapeutic significance of the antioxidant and prooxidant nanozymes in various disease model systems, such as cancer, neurodegeneration, and cardiovascular diseases. The future perspectives of this emerging area of research and the challenges associated with the biomedical applications of nanozymes are described.

Iridium-Based Nanohybrids: Synthesis, Characterization, Optical Limiting, and Nonlinear Optical Properties

The present work reports on the synthesis and characterization of iridium (Ir)-based nanohybrids with variable chemical compositions. More specifically, highly stable polyvinylpyrrolidone (PVP) nanohybrids of the PVP-IrO₂ and PVP-Ir/IrO₂ types, as well as non-coated Ir/IrO₂ nanoparticles, are synthesized using different synthetic protocols and characterized in terms of their chemical composition and morphology via X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM), respectively. Furthermore, their nonlinear optical (NLO) response and optical limiting (OL) efficiency are studied by means of the Z-scan technique, employing 4 ns laser pulses at 532 and 1064 nm. The results demonstrate that the PVP-Ir/IrO₂ and Ir/IrO₂ systems exhibit exceptional OL performance, while PVP-IrO₂ presents very strong saturable absorption (SA) behavior, indicating that the present Ir-based nanohybrids could be strong competitors to other nanostructured materials for photonic and optoelectronic applications. In addition, the findings denote that the variation in the content of IrO₂ nanoparticles by using different synthetic pathways significantly affects the NLO response of the studied Ir-based nanohybrids, suggesting that the choice of the appropriate synthetic method could lead to tailor-made NLO properties for specific applications in photonics and optoelectronics.

Unveiling the Role of Precursors in the Byproduct Formation of AgCl-Replicated Bimetallic Nanostructures and Their Stability-Dependent Photothermal Properties

AgCl nanomaterials recently attracted scientific interest as useful structural building blocks for producing metallic nanomaterials owing to their facile synthesis, controllable morphology, and ease of removal under ambient conditions. However, their complex chemical reactivity has primarily been studied in association with water solubility or reducibility. This study investigates the pivotal role of precursor ligands in the photochemical synthesis of metallic cubic mesh nanostructures on the AgCl templates. The side reactions between AgCl and Au precursors with different ligands are thoroughly discussed along with their influence on the byproduct formation and the structural stability of the resulting metallic nanostructures. Importantly, we introduce for the first time the partial destruction of AgCl and the formation of undesirable byproducts caused by the presence of highly oxidizing and Cl-containing AuCl₄^-. In addition, a synthetic route for producing highly pure and stable metallic nanostructures using a halogen-free Au precursor or Pt-priming is proposed. Further, the photothermal properties of these replicated metallic nanostructures are presented as a new evaluation tool for analyzing their overall structural stability. Discovering the role of precursor ligands in the reaction system will prove useful as a guide for the synthesis of functional noble metal nanomaterials using silver halide templates.

Characterization, catalytic, and recyclability studies of nano-sized spherical palladium particles synthesized using aqueous poly-extract (turmeric, neem, and tulasi)

Green synthesis of noble metal nanoparticles (NPs) has gained immense significance compared to other metal ions owing to their unique properties. Among them, palladium 'Pd' has been in the spotlight for its stable and superior catalytic activity. This work focuses on the synthesis of Pd NPs using the combined aqueous extract (poly-extract) of turmeric (rhizome), neem (leaves), and tulasi (leaves). The bio-synthesized Pd NPs were characterized to study its physicochemical and morphological features using several analytical techniques. Role of Pd NPs as nano-catalysts in the degradation of dyes (1 mg/2 mL stock solution) was evaluated in the presence of a strong reducing agent (sodium borohydride; SBH). In the presence of Pd NPs and SBH, maximum reduction of methylene blue (MB), methyl orange (MO), and rhodamine-B (Rh-B) dyes was observed under 20nullmin (96.55 ± 2.11%), 36nullmin (96.96 ± 2.24%), and 27nullmin (98.12 ± 1.33%), with degradation rate of 0.1789 ± 0.0273 min^-1, 0.0926 ± 0.0102 min^-1, and 0.1557 ± 0.0200 min^-1, respectively. In combination of dyes (MB + MO + Rh-B), maximum degradation was observed under 50nullmin (95.49 ± 2.56%) with degradation rate of 0.0694 ± 0.0087 min^-1. It was observed that degradation was following pseudo-first order reaction kinetics. Furthermore, Pd NPs showed good recyclability up to cycle 5 (72.88 ± 2.32%), cycle 9 (69.11 ± 2.19%) and cycle 6 (66.21 ± 2.72%) for MB, MO and Rh-B dyes, respectively. Whereas, up to cycle 4 (74.67 ± 0.66%) during combination of dyes. As Pd NPs showed good recyclability, they can be used for several cycles thus influencing the overall economics of the process.

Gold nanoparticles and gold nanorods in the landscape of cancer therapy

Cancer is a grievous disease whose treatment requires a more efficient, non-invasive therapy, associated with minimal side effects. Gold nanoparticles possessing greatly impressive optical properties have been a forerunner in bioengineered cancer therapy. This theranostic system has gained immense popularity and finds its application in the field of molecular detection, biological imaging, cancer cell targeting, etc. The photothermal property of nanoparticles, especially of gold nanorods, causes absorption of the light incident by the light source, and transforms it into heat, resulting in tumor cell destruction. This review describes the different optical features of gold nanoparticles and summarizes the advance research done for the application of gold nanoparticles and precisely gold nanorods for combating various cancers including breast, lung, colon, oral, prostate, and pancreatic cancer.

Smart Nanocarriers for the Targeted Delivery of Therapeutic Nucleic Acid for Cancer Immunotherapy

A wide variety of therapeutic approaches and technologies for delivering therapeutic agents have been investigated for treating cancer. Recently, immunotherapy has achieved success in cancer treatment. Successful clinical results of immunotherapeutic approaches for cancer treatment were led by antibodies targeting immune checkpoints, and many have advanced through clinical trials and obtained FDA approval. A major opportunity remains for the development of nucleic acid technology for cancer immunotherapy in the form of cancer vaccines, adoptive T-cell therapies, and gene regulation. However, these therapeutic approaches face many challenges related to their delivery to target cells, including their in vivo decay, the limited uptake by target cells, the requirements for nuclear penetration (in some cases), and the damage caused to healthy cells. These barriers can be avoided and resolved by utilizing advanced smart nanocarriers (e.g., lipids, polymers, spherical nucleic acids, metallic nanoparticles) that enable the efficient and selective delivery of nucleic acids to the target cells and/or tissues. Here, we review studies that have developed nanoparticle-mediated cancer immunotherapy as a technology for cancer patients. Moreover, we also investigate the crosstalk between the function of nucleic acid therapeutics in cancer immunotherapy, and we discuss how nanoparticles can be functionalized and designed to target the delivery and thus improve the efficacy, toxicity, and stability of these therapeutics.

In Situ Redox Synthesis of Highly Stable Au/Electroactive Polyimide Composite and Its Application on 4-Nitrophenol Reduction

In this study, we developed a series of Au/electroactive polyimide (Au/EPI-5) composite for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) using NaBH₄ as a reducing agent at room temperature. The electroactive polyimide (EPI-5) synthesis was performed by chemical imidization of its 4,4'-(4.4'-isopropylidene-diphenoxy) bis (phthalic anhydride) (BSAA) and amino-capped aniline pentamer (ACAP). In addition, prepare different concentrations of Au ions through the in-situ redox reaction of EPI-5 to obtain Au nanoparticles (AuNPs) and anchored on the surface of EPI-5 to form series of Au/EPI-5 composite. Using SEM and HR-TEM confirm the particle size (23-113 nm) of the reduced AuNPs increases with the increase of the concentration. Based on CV studies, the redox capability of as-prepared electroactive materials was found to show an increase trend: 1Au/EPI-5 < 3Au/EPI-5 < 5Au/EPI-5. The series of Au/EPI-5 composites showed good stability and catalytic activity for the reaction of 4-NP to 4-AP. Especially, the 5Au/EPI-5 composite shows the highest catalytic activity when applied for the reduction of 4-NP to 4-AP within 17 min. The rate constant and kinetic activity energy were calculated to be 1.1 × 10^-3 s^-1 and 38.9 kJ/mol, respectively. Following a reusability test repeated 10 times, the 5Au/EPI-5 composite maintained a conversion rate higher than 95%. Finally, this study elaborates the mechanism of the catalytic reduction of 4-NP to 4-AP.

A novel S,N-rich MOF for efficient recovery of Au(III): Performance and mechanism

A novel S,N-rich MOF with adenine and 4,4'-thiodiphenol as organic ligands was synthesized via the one-step solvothermal method, and used for gold recovery. The pH impact, adsorption kinetics, isotherms, thermodynamics, selectivity, and reusability were investigated accordingly. The adsorption and desorption mechanism were also explored comprehensively. The electronic attraction, coordination, and in situ redox account for the Au(III) adsorption. The Au(III) adsorption is affected strongly by the pH of solutions, and best at pH of 2.57. The MOF exhibits exceptional adsorption capacity as high as 3680 mg/g at 55 °C, fast kinetics with 8 min for 9.6 mg/L Au(III), and excellent selectivity for gold ion in real e-waste leachates. The adsorption process of gold on the adsorbent is endothermic and spontaneous, and influenced visibly by temperature. The adsorption ratio still maintained 99% after seven adsorption-desorption cycles. The column adsorption experiments show that the MOF has outstanding selectivity for Au(III) with 100% of removal efficiency in a complex solution containing Au, Ni, Cu, Cd, Co, and Zn ions. A glorious adsorption with a breakthrough time of 532 mins was obtained for the breakthrough curve. This study not only provides an efficient adsorbent for gold recovery, but also guidance for designing new materials.

Biosynthesis of Co3O4 nanomedicine by using Mollugo oppositifolia L. aqueous leaf extract and its antimicrobial, mosquito larvicidal activities

Nanotechnology is a relatively revolutionary area that generates day-to-day advancement. It makes a significant impact on our daily life. For example, in parasitology, catalysis and cosmetics, nanoparticles possess distinctive possessions that make it possible for them in a broad range of areas. We utilized Mollugo oppositifolia L. aqueous leaf extract assisted chemical reduction method to synthesize Co₃O₄ nanoparticles. Biosynthesized Co₃O₄ Nps were confirmed via UV-Vis spectroscopy, scanning electron microscope, X-ray diffraction, EDX, Fourier-transform infrared, and HR-TEM analysis. The crystallite size from XRD studies revealed around 22.7 nm. The biosynthesized Co₃O₄ nanoparticle was further assessed for mosquito larvicidal activity against south-urban mosquito larvae Culex quinquefasciatus, and antimicrobial activities. The synthesized Co₃O₄ particle (2) displayed significant larvicidal activity towards mosquito larvae Culex quinquefasciatus with the LD₅₀ value of 34.96 µg/mL than aqueous plant extract (1) and control Permethrin with the LD₅₀ value of 82.41 and 72.44 µg/mL. When compared to the standard antibacterial treatment, Ciprofloxacin, the Co₃O₄ nanoparticle (2) produced demonstrates significantly enhanced antibacterial action against the pathogens E. coli and B. cereus. The MIC for Co₃O₄ nanoparticles 2 against C. albicans was under 1 μg/mL, which was much lower than the MIC for the control drug, clotrimale, which was 2 µg per milliliter. Co₃O₄ nanoparticles 2, with a MIC of 2 μg/mL, has much higher antifungal activity than clotrimale, whose MIC is 4 μg/mL, against M. audouinii.

A Systemic Review on the Synthesis, Characterization, and Applications of Palladium Nanoparticles in Biomedicine

Palladium nanoparticles (Pd NPs) have been considered as a potential candidate in the field of biomedical applications due to its unique properties such as huge catalytic, hydrogen storage, and sensing behavior. Therefore, Pd NPs have shown to have a significant potential for the development of antimicrobials, wound healing, antioxidant, and anticancer property in recent days. There are plenty of reports that showed superior properties of noble metals. However, only very few studies have been undertaken to explore the advantage of Pd NPs in the field of biomedical applications. This review reports detailed and comprehensive studies comprising of the synthesis, characterization, and potential applications of Pd NPs in biomedicine. This report provides evidences in the literature documented by early researchers to understand the potential applications of Pd NPs to be explored in various fields.

Electrochemical Biosensors for Whole Blood Analysis: Recent Progress, Challenges, and Future Perspectives

Whole blood, as one of the most significant biological fluids, provides critical information for health management and disease monitoring. Over the past 10 years, advances in nanotechnology, microfluidics, and biomarker research have spurred the development of powerful miniaturized diagnostic systems for whole blood testing toward the goal of disease monitoring and treatment. Among the techniques employed for whole-blood diagnostics, electrochemical biosensors, as known to be rapid, sensitive, capable of miniaturization, reagentless and washing free, become a class of emerging technology to achieve the target detection specifically and directly in complex media, e.g., whole blood or even in the living body. Here we are aiming to provide a comprehensive review to summarize advances over the past decade in the development of electrochemical sensors for whole blood analysis. Further, we address the remaining challenges and opportunities to integrate electrochemical sensing platforms.

Green Nanoformulations of Polyvinylpyrrolidone-Capped Metal Nanoparticles: A Study at the Hybrid Interface with Biomimetic Cell Membranes and In Vitro Cell Models

Noble metal nanoparticles (NP) with intrinsic antiangiogenic, antibacterial, and anti-inflammatory properties have great potential as potent chemotherapeutics, due to their unique features, including plasmonic properties for application in photothermal therapy, and their capability to slow down the migration/invasion speed of cancer cells and then suppress metastasis. In this work, gold (Au), silver (Ag), and palladium (Pd) NP were synthesized by a green redox chemistry method with the reduction of the metal salt precursor with glucose in the presence of polyvinylpyrrolidone (PVP) as stabilizing and capping agent. The physicochemical properties of the PVP-capped NP were investigated by UV-visible (UV-vis) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopies, dynamic light scattering (DLS), and atomic force microscopy (AFM), to scrutinize the optical features and the interface between the metal surface and the capping polymer, the hydrodynamic size, and the morphology, respectively. Biophysical studies with model cell membranes were carried out by using laser scanning confocal microscopy (LSM) with fluorescence recovery after photobleaching (FRAP) and fluorescence resonance energy transfer (FRET) techniques. To this purpose, artificial cell membranes of supported lipid bilayers (SLBs) made with 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine (POPC) dye-labeled with 7-nitro-2-1,3-benzoxadiazol-4-yl (NBD, FRET donor) and/or lissamine rhodamine B sulfonyl (Rh, FRET acceptor) were prepared. Proof-of-work in vitro cellular experiments were carried out with prostate cancer cells (PC-3 line) in terms of cytotoxicity, cell migration (wound scratch assay), NP cellular uptake, and cytoskeleton actin perturbation.

Immunotoxicity of metal and metal oxide nanoparticles: from toxic mechanisms to metabolism and outcomes

The influence of metal and metal oxide nanomaterials on various fields since their discovery has been remarkable. They have unique properties, and therefore, have been employed in specific applications, including biomedicine. However, their potential health risks cannot be ignored. Several studies have shown that exposure to metal and metal oxide nanoparticles can lead to immunotoxicity. Different types of metals and metal oxide nanoparticles may have a negative impact on the immune system through various mechanisms, such as inflammation, oxidative stress, autophagy, and apoptosis. As an essential factor in determining the function and fate of immune cells, immunometabolism may also be an essential target for these nanoparticles to exert immunotoxic effects in vivo. In addition, the biodegradation and metabolic outcomes of metal and metal oxide nanoparticles are also important considerations in assessing their immunotoxic effects. Herein, we focus on the cellular mechanism of the immunotoxic effects and toxic effects of different types of metal and metal oxide nanoparticles, as well as the metabolism and outcomes of these nanoparticles in vivo. Also, we discuss the relationship between the possible regulatory effect of nanoparticles on immunometabolism and their immunotoxic effects. Finally, we present perspectives on the future research and development direction of metal and metal oxide nanomaterials to promote scientific research on the health risks of nanomaterials and reduce their adverse effects on human health.

Synthesis Methods and Optical Sensing Applications of Plasmonic Metal Nanoparticles Made from Rhodium, Platinum, Gold, or Silver

The purpose of this paper is to provide an in-depth review of plasmonic metal nanoparticles made from rhodium, platinum, gold, or silver. We describe fundamental concepts, synthesis methods, and optical sensing applications of these nanoparticles. Plasmonic metal nanoparticles have received a lot of interest due to various applications, such as optical sensors, single-molecule detection, single-cell detection, pathogen detection, environmental contaminant monitoring, cancer diagnostics, biomedicine, and food and health safety monitoring. They provide a promising platform for highly sensitive detection of various analytes. Due to strongly localized optical fields in the hot-spot region near metal nanoparticles, they have the potential for plasmon-enhanced optical sensing applications, including metal-enhanced fluorescence (MEF), surface-enhanced Raman scattering (SERS), and biomedical imaging. We explain the plasmonic enhancement through electromagnetic theory and confirm it with finite-difference time-domain numerical simulations. Moreover, we examine how the localized surface plasmon resonance effects of gold and silver nanoparticles have been utilized for the detection and biosensing of various analytes. Specifically, we discuss the syntheses and applications of rhodium and platinum nanoparticles for the UV plasmonics such as UV-MEF and UV-SERS. Finally, we provide an overview of chemical, physical, and green methods for synthesizing these nanoparticles. We hope that this paper will promote further interest in the optical sensing applications of plasmonic metal nanoparticles in the UV and visible ranges.

Research Progress on Biomimetic Nanomaterials for Electrochemical Glucose Sensors

Diabetes has become a chronic disease that necessitates timely and accurate detection. Among various detection methods, electrochemical glucose sensors have attracted much attention because of low cost, real-time detection, and simple and easy operation. Nonenzymatic biomimetic nanomaterials are the vital part in electrochemical glucose sensors. This review article summarizes the methods to enhance the glucose sensing performance of noble metal, transition metal oxides, and carbon-based materials and introduces biomimetic nanomaterials used in noninvasive glucose detection in sweat, tear, urine, and saliva. Based on these, this review provides the foundation for noninvasive determination of trace glucose for diabetic patients in the future.

Feasibility of Coacervate-Like Nanostructure for Instant Drug Nanoformulation

Despite the enormous advancements in nanomedicine research, a limited number of nanoformulations are available on the market, and few have been translated to clinics. An easily scalable, sustainable, and cost-effective manufacturing strategy and long-term stability for storage are crucial for successful translation. Here, we report a system and method to instantly formulate NF achieved with a nanoscale polyelectrolyte coacervate-like system, consisting of anionic pseudopeptide poly(l-lysine isophthalamide) derivatives, polyethylenimine, and doxorubicin (Dox) via simple "mix-and-go" addition of precursor solutions in seconds. The coacervate-like nanosystem shows enhanced intracellular delivery of Dox to patient-derived multidrug-resistant (MDR) cells in 3D tumor spheroids. The results demonstrate the feasibility of an instant drug formulation using a coacervate-like nanosystem. We envisage that this technique can be widely utilized in the nanomedicine field to bypass the special requirement of large-scale production and elongated shelf life of nanomaterials.

Shape-Controlled Synthesis of Platinum-Based Nanocrystals and Their Electrocatalytic Applications in Fuel Cells

To achieve environmentally benign energy conversion with the carbon neutrality target via electrochemical reactions, the innovation of electrocatalysts plays a vital role in the enablement of renewable resources. Nowadays, Pt-based nanocrystals (NCs) have been identified as one class of the most promising candidates to efficiently catalyze both the half-reactions in hydrogen- and hydrocarbon-based fuel cells. Here, we thoroughly discuss the key achievement in developing shape-controlled Pt and Pt-based NCs, and their electrochemical applications in fuel cells. We begin with a mechanistic discussion on how the morphology can be precisely controlled in a colloidal system, followed by highlighting the advanced development of shape-controlled Pt, Pt-alloy, Pt-based core@shell NCs, Pt-based nanocages, and Pt-based intermetallic compounds. We then select some case studies on models of typical reactions (oxygen reduction reaction at the cathode and small molecular oxidation reaction at the anode) that are enhanced by the shape-controlled Pt-based nanocatalysts. Finally, we provide an outlook on the potential challenges of shape-controlled nanocatalysts and envision their perspective with suggestions.

Metal-Organic Frameworks as Sensors for Human Amyloid Diseases

Metal-organic frameworks (MOFs) are versatile compounds with emergent applications in the fabrication of biosensors for amyloid diseases. They hold great potential in biospecimen protection and unprecedented probing capabilities for optical and redox receptors. In this Review, we summarize the main methodologies employed in the fabrication of MOF-based sensors for amyloid diseases and collect all available data in the literature related to their performance (detection range, limit of detection, recovery, time of analysis, among other parameters). Nowadays, MOF sensors have evolved to a point where they can, in some cases, outperform technologies employed in the detection of several amyloid biomarkers (amyloid β peptide, α-synuclein, insulin, procalcitonin, and prolactin) present in biological fluids, such as cerebrospinal fluid and blood. A special emphasis has been given by researchers on Alzheimer's disease monitoring to the detriment of other amyloidosis that are underexploited despite their societal relevance (e.g., Parkinson's disease). There are still important obstacles to overcome in order to selectively detect the various peptide isoforms and soluble amyloid species associated with Alzheimer's disease. Furthermore, MOF contrast agents for imaging peptide soluble oligomers in living humans are also scarce (if not nonexistent), and action in this direction is unquestionably required to clarify the contentious link between the amyloidogenic species and the disease, guiding research toward the most promising therapeutic strategies.

Oxygen-generating biocatalytic nanomaterials for tumor hypoxia relief in cancer radiotherapy

Radiotherapy (RT), the most commonly used treatment method in clinics, shows unique advantages such as strong penetration, high energy intensity, and low systemic side effects. However, in vivo tumor hypoxia seriously hinders the therapeutic effect of RT. Hypoxia is a common characteristic of locally advanced solid tumor microenvironments, which leads to the proliferation, invasion and metastasis of tumor cells. In addition, oxygen consumption during RT will further aggravate tumor hypoxia, causing a variety of adverse side effects. In recent years, various biocatalytic nanomaterials (BCNs) have been explored to regulate and reverse tumor hypoxia microenvironments during RT. In this review, the most recent efforts toward developing oxygen-generating BCNs in relieving tumor hypoxia in RT are focused upon. The classification, engineering nanocatalytical activity of oxygen-generating BCNs and combined therapy based on these BCNs are systematically introduced and discussed. The challenges and prospects of these oxygen-generating BCNs in RT applications are also summarized.