Multifunctional magnetic nanoparticles for targeted imaging and therapy

Advanced Delivery Strategies of Nintedanib for Lung Disorders and Beyond: A Comprehensive Review

Nintedanib, a primary treatment for lung fibrosis, has gathered substantial attention due to its multifaceted potential. A tyrosine kinase inhibitor, nintedanib, inhibits multiple signalling receptors, including endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and fibroblast growth factor receptor (FGFR) and ultimately inhibits fibroblast proliferation and differentiation. Therefore, nintedanib has been studied widely for other ailments like cancers and hepatic fibrosis, apart from lung disorders. Commercially, nintedanib is available as soft gelatin capsules for treatment against idiopathic pulmonary fibrosis. Since it has very low oral bioavailability (4.7%), high doses of a drug, such as 100-150 mg, are administered, which can cause problems of gastrointestinal irritation and hepatotoxicity. The article begins with exploring the mechanism of action of nintedanib, elucidating its complex interactions within cellular pathways that govern fibrotic processes. It also emphasizes the pharmacokinetics of nintedanib, clinical trial insights, and the limitations of conventional formulations. The article mainly focuses on the emerging landscape of nanoparticle-based carriers such as hybrid liposome-exosome, nano liquid crystals, discoidal polymeric, and magnetic systems, offering promising avenues to optimize drug targeting, address its efficacy issues and minimise adverse effects. However, none of these delivery systems are commercialised, and further research is required to ensure safety and effectiveness in clinical settings. Yet, as research progresses, these advanced delivery systems promise to revolutionise the treatment landscape for various fibrotic disorders and cancers, potentially improving patient outcomes and quality of life.

A minimally invasive thrombotic stroke model to study circadian rhythm in awake mice

Experimental stroke models in rodents are essential for mechanistic studies and therapeutic development. However, these models have several limitations negatively impacting their translational relevance. Here we aimed to develop a minimally invasive thrombotic stroke model through magnetic particle delivery that does not require craniotomy, is amenable to reperfusion therapy, can be combined with in vivo imaging modalities, and can be performed in awake mice. We found that the model results in reproducible cortical infarcts within the middle cerebral artery (MCA) with cytologic and immune changes similar to that observed with more invasive distal MCA occlusion models. Importantly, the injury produced by the model was ameliorated by tissue plasminogen activator (tPA) administration. We also show that MCA occlusion in awake animals results in bigger ischemic lesions independent of day/night cycle. Magnetic particle delivery had no overt effects on physiologic parameters and systemic immune biomarkers. In conclusion, we developed a novel stroke model in mice that fulfills many requirements for modeling human stroke.

Synthesis, modifications, and applications of iron-based nanoparticles

Magnetic nanoparticles (MNPs) are appealing materials as assistant to resolve environmental pollution issues and as recyclable catalysts for the oxidative degradation of resistant contaminants. Moreover, they can significantly influence the advancement of medical applications for imaging, diagnostics, medication administration, and biosensing. On the other hand, due to unique features, excellent biocompatibility, high curie temperatures and low cytotoxicity of the Iron-based nanoparticles, they have received increasing attention in recent years. Using an external magnetic field, in which the ferrite magnetic nanoparticles (FMNPs) in the reaction mixtures can be easily removed, make them more efficient approach than the conventional method for separating the catalyst particles by centrifugation or filtration. Ferrite magnetic nanoparticles (FMNPs) provide various advantages in food processing, environmental issues, pharmaceutical industry, sample preparation, wastewater management, water purification, illness therapy, identification of disease, tissue engineering, and biosensor creation for healthcare monitoring. Modification of FMNPs with the proper functional groups and surface modification techniques play a significant role in boosting their capability. Due to flexibility of FMNPs in functionalization and synthesis, it is possible to make customized FMNPs that can be utilized in variety of applications. This review focuses on synthesis, modifications, and applications of Iron-based nanoparticles.

New Types of Magnetic Nanoparticles for Stimuli-Responsive Theranostic Nanoplatforms

Magnetic nanomaterials have played a crucial role in promoting the application of nanotechnology in the biomedical field. Although conventional magnetic nanomaterials such as iron oxide nanoparticles (NPs) are used as biosensors, drug delivery vehicles, diagnostic and treatment agents for several diseases, the persistent pursuit of high-performance technologies has prompted researchers to continuously develop new types of magnetic nanomaterials such as iron carbide NPs. Considering their potential application in biomedicine, magnetic NPs responsive to exogenous or endogenous stimuli are developed, thereby enhancing their applicability in more complex versatile scenarios. In this review, the synthesis and surface modification of magnetic NPs are focused, particularly iron carbide NPs. Subsequently, exogenous and endogenous stimuli-responsive magnetic NP-based theranostic platforms are introduced, particularly focusing on nanozyme-based technologies and magnetic NP-mediated immunotherapy, which are emerging stimuli-responsive treatments. Finally, the challenges and perspectives of magnetic NPs to accelerate future research in this field are discussed.

Nano-delivery systems as a promising therapeutic potential for epilepsy: Current status and future perspectives

Epilepsy is a common chronic neurological disorder caused by aberrant neuronal electrical activity. Antiseizure medications (ASMs) are the first line of treatment for people with epilepsy (PWE). However, their effectiveness may be limited by their inability to cross the blood-brain barrier (BBB), among many other potential underpinnings for drug resistance in epilepsy. Therefore, there is a need to overcome this issue and, hopefully, improve the effectiveness of ASMs. Recently, synthetic nanoparticle-based drug delivery systems have received attention for improving the effectiveness of ASMs due to their ability to cross the BBB. Furthermore, exosomes have emerged as a promising generation of drug delivery systems because of their potential benefits over synthetic nanoparticles. In this narrative review, we focus on various synthetic nanoparticles that have been studied to deliver ASMs. Furthermore, the benefits and limitations of each nano-delivery system have been discussed. Finally, we discuss exosomes as potentially promising delivery tools for treating epilepsy.

Vascular endothelial growth factor (VEGF) delivery approaches in regenerative medicine

The utilization of growth factors in the process of tissue regeneration has garnered significant interest and has been the subject of extensive research. However, despite the fervent efforts invested in recent clinical trials, a considerable number of these studies have produced outcomes that are deemed unsatisfactory. It is noteworthy that the trials that have yielded the most satisfactory outcomes have exhibited a shared characteristic, namely, the existence of a mechanism for the regulated administration of growth factors. Despite the extensive exploration of drug delivery vehicles and their efficacy in delivering certain growth factors, the development of a reliable predictive approach for the delivery of delicate growth factors like Vascular Endothelial Growth Factor (VEGF) remains elusive. VEGF plays a crucial role in promoting angiogenesis; however, the administration of VEGF demands a meticulous approach as it necessitates precise localization and transportation to a specific target tissue. This process requires prolonged and sustained exposure to a low concentration of VEGF. Inaccurate administration of drugs, either through off-target effects or inadequate delivery, may heighten the risk of adverse reactions and potentially result in tumorigenesis. At present, there is a scarcity of technologies available for the accurate encapsulation of VEGF and its subsequent sustained and controlled release. The objective of this review is to present and assess diverse categories of VEGF administration mechanisms. This paper examines various systems, including polymeric, liposomal, hydrogel, inorganic, polyplexes, and microfluidic, and evaluates the appropriate dosage of VEGF for multiple applications.

Copper ferrite nanoparticles catalyzed the challenging Diels-Alder reaction of aromatic chalcones with cyclopentadiene

Copper ferrite nanoparticles efficiently transformed the unreactive aromatic chalcones into activated dienophiles for a Diels-Alder reaction with cyclopentadiene/isoprene as dienes. The best results in terms of rate of reaction and product yields were obtained in an eco-friendly solvent i.e. ethanol using 5 mol% catalytic loading. Substrate scope was also investigated for a number of chalcone derivatives, and all the reactions proceeded smoothly to provide the corresponding DA adducts in high yields (up to 89%) and good diastereoselectivities (up to >99%) with endo-preference.

Size dependence of the surface spin disorder and surface anisotropy constant in ferrite nanoparticles

The magnetic properties of nanoscale magnets are greatly influenced by surface anisotropy. So far, its quantification is based on the examination of the blocking temperature shift within a series of nanoparticles of varying sizes. In this scenario, the surface anisotropy is assumed to be a particle size-independent quantity. However, there is no solid experimental proof to support this simplified picture. On the contrary, our work unravels the size-dependent magnetic morphology and surface anisotropy in highly uniform magnetic nanoparticles using small-angle polarized neutron scattering. We observed that the surface anisotropy constant does not depend on the nanoparticle's size in the range of 3-9 nm. Furthermore, our results demonstrate that the surface spins are less prone to polarization with increasing nanoparticle size. Our study thus proves the size dependence of the surface spin disorder and the surface anisotropy constant in fine nanomagnets. These findings open new routes in materials based on a controlled surface spin disorder, which is essential for future applications of nanomagnets in biomedicine and magnonics.

Multifunctional Properties of Polyhedral Oligomeric Silsesquioxanes (POSS)-Based Epoxy Nanocomposites

In this study, a tetrafunctional epoxy resin was loaded with 5 wt% of three different types of polyhedral oligomeric silsesquioxane (POSS) compounds, namely, DodecaPhenyl POSS (DPHPOSS), Epoxycyclohexyl POSS (ECPOSS), Glycidyl POSS (GPOSS), and 0.5 wt% of multi-walled carbon nanotubes (CNTs) in order to formulate multifunctional structural nanocomposites tailored for aeronautic and aerospace applications. This work aims to demonstrate how the skillful combination of desired properties, such as good electrical, flame-retardant, mechanical, and thermal properties, is obtainable thanks to the advantages connected with nanoscale incorporations of nanosized CNTs with POSS. The special hydrogen bonding-based intermolecular interactions between the nanofillers have proved to be strategic in imparting multifunctionality to the nanohybrids. All multifunctional formulations are characterized by a Tg centered at values close to 260 °C, fully satisfying structural requirements. Infrared spectroscopy and thermal analysis confirm the presence of a cross-linked structure characterized by a high curing degree of up to 94% and high thermal stability. Tunneling atomic force microscopy (TUNA) allows to detect the map of the electrical pathways at the nanoscale of the multifunctional samples, highlighting a good dispersion of the carbon nanotubes within the epoxy resin. The combined action of POSS with CNTs has allowed to obtain the highest values of self-healing efficiency if compared to those measured for samples containing only POSS in the absence of CNTs.

Nanoparticles for MRI-guided radiation therapy: a review

The development of nanoparticle agents for MRI-guided radiotherapy is growing at an increasing pace, with clinical trials now underway and many pre-clinical evaluation studies ongoing. Gadolinium and iron-oxide-based nanoparticles remain the most clinically advanced nanoparticles to date, although several promising candidates are currently under varying stages of development. Goals of current and future generation nanoparticle-based contrast agents for MRI-guided radiotherapy include achieving positive signal contrast on T1-weighted MRI scans, local radiation enhancement at clinically relevant concentrations and, where applicable, avoidance of uptake by the reticuloendothelial system. Exploiting the enhanced permeability and retention effect or the use of active targeting ligands on nanoparticle surfaces is utilised to promote tumour uptake. This review outlines the current status of promising nanoparticle agents for MRI-guided radiation therapy, including several platforms currently undergoing clinical evaluation or at various stages of the pre-clinical development process. Challenges facing nanoparticle agents and possible avenues for current and future development are discussed.

Synthesis of Carbon-Encapsulated Magnetic Iron Oxide Nanocomposites for Bioapplication

Carbon-encapsulated Fe3O4 nanoparticles (NPs) were successfully synthesized from a single precursor using one-step solvothermal methods. X-ray diffraction and transmission electron microscopy were used to characterize the as-prepared NPs, and UV-visible absorbance spectroscopy was used to check their optical properties. The morphological results revealed that Fe3O4@C, quasi-spherical Fe3O4 particles encapsulated by carbon. In addition, the carbon-encapsulated Fe3O4 NPs were conjugated with folic acid (FA) to be used as biomarkers in the diagnosis and treatment of tumour cells. Fourier transform infrared spectroscopy and UV-visible spectroscopic techniques were used to confirm the conjugation process.

Facets of ICP-MS and their potential in the medical sciences—Part 2: nanomedicine, immunochemistry, mass cytometry, and bioassays

Inductively coupled–plasma mass spectrometry (ICP-MS) has transformed our knowledge on the role of trace and major elements in biology and has emerged as the most versatile technique in elemental mass spectrometry. The scope of ICP-MS has dramatically changed since its inception, and nowadays, it is a mature platform technology that is compatible with chromatographic and laser ablation (LA) systems. Over the last decades, it kept pace with various technological advances and was inspired by interdisciplinary approaches which endorsed new areas of applications. While the first part of this review was dedicated to fundamentals in ICP-MS, its hyphenated techniques and the application in biomonitoring, isotope ratio analysis, elemental speciation analysis, and elemental bioimaging, this second part will introduce relatively current directions in ICP-MS and their potential to provide novel perspectives in the medical sciences. In this context, current directions for the characterisation of novel nanomaterials which are considered for biomedical applications like drug delivery and imaging platforms will be discussed while considering different facets of ICP-MS including single event analysis and dedicated hyphenated techniques. Subsequently, immunochemistry techniques will be reviewed in their capability to expand the scope of ICP-MS enabling analysis of a large range of biomolecules alongside elements. These methods inspired mass cytometry and imaging mass cytometry and have the potential to transform diagnostics and treatment by offering new paradigms for personalised medicine. Finally, the interlacing of immunochemistry methods, single event analysis, and functional nanomaterials has opened new horizons to design novel bioassays which promise potential as assets for clinical applications and larger screening programs and will be discussed in their capabilities to detect low-level proteins and nucleic acids.

Synthesis and preclinical application of a Prussian blue-based dual fluorescent and magnetic contrast agent (CA)

The aim of this study was to develop and characterize a Prussian Blue based biocompatible and chemically stable T1 magnetic resonance imaging (MRI) contrast agent with near infrared (NIR) optical contrast for preclinical application. The physical properties of the Prussian blue nanoparticles (PBNPs) (iron (II); iron (III);octadecacyanide) were characterized with dynamic light scattering (DLS), zeta potential measurement, atomic force microscopy (AFM), and transmission electron microscopy (TEM). In vitro contrast enhancement properties of PBNPs were determined by MRI. In vivo T1-weighted contrast of the prepared PBNPs was investigated by MRI and optical imaging modality after intravenous administration into NMRI-Foxn1 nu/nu mice. The biodistribution studies showed the presence of PBNPs predominantly in the cardiovascular system. Briefly, in this paper we show a novel approach for the synthesis of PBNPs with enhanced iron content for T1 MRI contrast. This newly synthetized PBNP platform could lead to a new diagnostic agent, replacing the currently used Gadolinium based substances.

Molecular imaging nanoprobes for theranostic applications

As a non-invasive imaging monitoring method, molecular imaging can provide the location and expression level of disease signature biomolecules in vivo, leading to early diagnosis of relevant diseases, improved treatment strategies, and accurate assessment of treating efficacy. In recent years, a variety of nanosized imaging probes have been developed and intensively investigated in fundamental/translational research and clinical practice. Meanwhile, as an interdisciplinary discipline, this field combines many subjects of chemistry, medicine, biology, radiology, and material science, etc. The successful molecular imaging not only requires advanced imaging equipment, but also the synthesis of efficient imaging probes. However, limited summary has been reported for recent advances of nanoprobes. In this paper, we summarized the recent progress of three common and main types of nanosized molecular imaging probes, including ultrasound (US) imaging nanoprobes, magnetic resonance imaging (MRI) nanoprobes, and computed tomography (CT) imaging nanoprobes. The applications of molecular imaging nanoprobes were discussed in details. Finally, we provided an outlook on the development of next generation molecular imaging nanoprobes.

Endothelial Cell Adhesion Molecules- (un)Attainable Targets for Nanomedicines

Endothelial cell adhesion molecules have long been proposed as promising targets in many pathologies. Despite promising preclinical data, several efforts to develop small molecule inhibitors or monoclonal antibodies (mAbs) against cell adhesion molecules (CAMs) ended in clinical-stage failure. In parallel, many well-validated approaches for targeting CAMs with nanomedicine (NM) were reported over the years. A wide range of potential applications has been demonstrated in various preclinical studies, from drug delivery to the tumor vasculature, imaging of the inflamed endothelium, or blocking immune cells infiltration. However, no NM drug candidate emerged further into clinical development. In this review, we will summarize the most advanced examples of CAM-targeted NMs and juxtapose them with known traditional drugs against CAMs, in an attempt to identify important translational hurdles. Most importantly, we will summarize the proposed strategies to enhance endothelial CAM targeting by NMs, in an attempt to offer a catalog of tools for further development.

Biomedical applications of polysaccharide nanoparticles for chronic inflammatory disorders: Focus on rheumatoid arthritis, diabetes and organ fibrosis

Polysaccharides are biopolymers distinguished by their complex secondary structures executing various roles in microorganisms, plants, and animals. They are made up of long monomers of similar type or as a combination of other monomeric chains. Polysaccharides are considered superior as compared to other polymers due to their diversity in charge and size, biodegradability, abundance, bio-compatibility, and less toxicity. These natural polymers are widely used in designing of nanoparticles (NPs) which possess wide applications in therapeutics, diagnostics, delivery and protection of bioactive compounds or drugs. The side chain reactive groups of polysaccharides are advantageous for functionalization with nanoparticle-based conjugates or therapeutic agents such as small molecules, proteins, peptides and nucleic acids. Polysaccharide NPs show excellent pharmacokinetic and drug delivery properties, facilitate improved oral absorption, control the release of drugs, increases in vivo retention capability, targeted delivery, and exert synergistic effects. This review updates the usage of polysaccharides based NPs particularly cellulose, chitosan, hyaluronic acid, alginate, dextran, starch, cyclodextrins, pullulan, and their combinations with promising applications in diabetes, organ fibrosis and arthritis.

PLGA-Gold Nanocomposite: Preparation and Biomedical Applications

A composite system consisting of both organic and inorganic nanoparticles is an approach to prepare a new material exhibiting “the best of both worlds”. In this review, we highlight the recent advances in the preparation and applications of poly(lactic-co-glycolic acid)-gold nanoparticles (PLGA-GNP). With its current clinically use, PLGA-based nanocarriers have promising pharmaceutical applications and can “extract and utilize” the fascinating optical and photothermal properties of encapsulated GNP. The resulting “golden polymeric nanocarrier” can be tracked, analyzed, and visualized using the encapsulated gold nanoprobes which facilitate a better understanding of the hosting nanocarrier’s pharmacokinetics and biological fate. In addition, the “golden polymeric nanocarrier” can reveal superior nanotherapeutics that combine both the photothermal effect of the encapsulated gold nanoparticles and co-loaded chemotherapeutics. To help stimulate more research on the development of nanomaterials with hybrid and exceptional properties, functionalities, and applications, this review provides recent examples with a focus on the available chemistries and the rationale behind encapsulating GNP into PLGA nanocarriers that has the potential to be translated into innovative, clinically applicable nanomedicine.

Enhanced thermodynamic, pharmacokinetic and theranostic properties of polymeric micelles via hydrophobic core-clustering of superparamagnetic iron oxide nanoparticles

Background

Superparamagnetic iron oxide nanoparticles (SPIO) have been applied for decades to design theranostic polymeric micelles for targeted cancer therapy and diagnostic MR imaging. However, the effects of SPIO on the physicochemical, and biological properties of polymeric micelles have not yet been fully elucidated. Therefore, we investigated potential effect of SPIO on the physical and biological properties of theranostic polymeric micelles using representative cancer drug (doxorubicin; Doxo) and polymer carrier (i.e., poly (ethylene glycol)-co-poly(D,L-lactide), PEG-PLA).

Methods

SPIO were synthesized from Fe(acetyl acetonate)₃ in an aryl ether. SPIO and Doxo were loaded into the polymeric micelles by a solvent-evaporation method. We observed the effect of SPIO-clustering on drug loading, micelle size, thermodynamic stability, and theranostic property of PEG-PLA polymeric micelles. In addition, cellular uptake behaviors, pharmacokinetic and biodistribution study were performed.

Results

SPIO formed hydrophobic geometric cavity in the micelle core and significantly affected the integrity of micelles in terms of micelle size, Doxo loading, critical micelle concentration (CMC) and in vitro dissociation. In vivo pharmacokinetic studies also showed the enhanced Area Under Curve (AUC) and elongated the half-life of Doxo.

Conclusions

Clustered SPIO in micelles largely affects not only MR imaging properties but also biological and physical properties of polymeric micelles.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40824-022-00255-9.

Poly(2-oxazoline)-magnetite NanoFerrogels: Magnetic field responsive theranostic platform for cancer drug delivery and imaging

Combining diagnosis and treatment approaches in one entity is the goal of theranostics for cancer therapy. Magnetic nanoparticles have been extensively used as contrast agents for nuclear magnetic resonance imaging as well as drug carriers and remote actuation agents. Poly(2-oxazoline)-based polymeric micelles, which have been shown to efficiently solubilize hydrophobic drugs and drug combinations, have high loading capacity (above 40% w/w) for paclitaxel. In this study, we report the development of novel theranostic system, NanoFerrogels, which is designed to capitalize on the magnetic nanoparticle properties as imaging agents and the poly(2-oxazoline)-based micelles as drug loading compartment. We developed six formulations with magnetic nanoparticle content of 0.3%-12% (w/w), with the z-average sizes of 85-130 nm and ξ-potential of 2.7-28.3 mV. The release profiles of paclitaxel from NanoFerrogels were notably dependent on the degree of dopamine grafting on poly(2-oxazoline)-based micelles. Paclitaxel loaded NanoFerrogels showed efficacy against three breast cancer lines which was comparable to free paclitaxel. They also showed improved tumor and lymph node accumulation and signal reduction in vivo (2.7% in tumor; 8.5% in lymph node) compared to clinically approved imaging agent ferumoxytol (FERAHEME®) 24 h after administration. NanoFerrogels responded to super-low frequency alternating current magnetic field (50 kA m-1, 50 Hz) which accelerated drug release from paclitaxel-loaded NanoFerrogels or caused death of cells loaded with NanoFerrogels. These proof-of-concept experiments demonstrate that NanoFerrogels have potential as remotely actuated theranostic platform for cancer diagnosis and treatment.

Hepatic and renal cellular cytotoxic effects of heparin-coated superparamagnetic Iron oxide nanoparticles

Background

Superparamagnetic iron oxide (SPIO) nanoparticles have been widely used in several biomedical engineering in vivo. Although various surface modifications have been made to these non-biodegradable nanoparticles to make them more biocompatible, their toxic potential still remains a major concern.

Method

In this study, we newly developed unfractionated heparin (UFH)-coated and low molecular weight heparin (LMWH)-coated SPIO nanoparticles through surface modification engineering, which was compared with commercially available dextran-coated SPIO nanoparticles. Their toxicity such as cytotoxicity, single cell gel electrophoresis (SCGE) comet assay, intracellular reactive oxygen species (ROS) content and cellular apoptosis was evaluated to hepatic HepG2 and renal HK-2 cells.

Results

When UFH-, LMWH- or dextran-coated SPIO nanoparticles were applied, they did not affect the viability of HepG2 cell. However, HK-2 cells were more sensitive to dextran-coated SPIO nanoparticles than others. In genotoxicity assay using SCGE comet, DNA tail moment values in the groups treated with dextran- and LMWH-coated SPIO nanoparticles significantly increased. However, UFH-coated SPIO nanoparticles was only significantly lowing DNA tail moment value. In addition, UFH-coated SPIO nanoparticles had lower cytotoxicity in HepG2 and HK-2 cells compared to dextran-coated SPIO nanoparticles, especially in terms of apoptosis and intracellular ROS production.

Conclusions

Collectively, it is possible that UFH- coated SPIO nanoparticles can be used as alternative negative contrast agents.

Deep Learned Super Resolution of System Matrices for Magnetic Particle Imaging

Magnetic Particle Imaging (MPI) is a new imaging technique that allows high resolution & high frame-rate imaging of magnetic nanoparticles (MNP). It relies on the nonlinear response of MNPs under a magnetic field. The imaging process can be modeled linearly, and then image reconstruction can be case as an inverse problem using a measured system matrix (SM). However, this calibration measurement is time consuming so it reduces practicality. In this study, we proposed a novel method for accelerating the SM calibration based on joint super-resolution (SR) and denoising of sensitivty maps (i.e., rows of SM). The proposed method is based on a deep convolutional neural network (CNN) architecture with residual-dense blocks. Model training was performed using noisy SM measurements simulated for varying MNP size and gradient strengths. Comparisons were performed against conventional low-resolution SM calibration, noisy high-resolution SM calibration, and bicubic upsampling of low-resolution SM. We show that the proposed method improves high-resolution SM recovery, and in turn leads to improved resolution and quality in subsequently reconstructed MPI images.

Recent Advances in Gadolinium Based Contrast Agents for Bioimaging Applications

Gadolinium (Gd) based contrast agents (CAs) (Gd-CAs) represent one of the most advanced developments in the application of Gd for magnetic resonance imaging (MRI). Current challenges with existing CAs generated an urgent requirement to develop multimodal CAs with good biocompatibility, low toxicity, and prolonged circulation time. This review discussed the Gd-CAs used in bioimaging applications, addressing their advantages and limitations. Future research is required to establish the safety, efficacy and theragnostic capabilities of Gd-CAs. Nevertheless, these Gd-CAs offer extraordinary potential as imaging CAs and promise to benefit bioimaging applications significantly.

Iron Oxide Nanoparticles in Regenerative Medicine and Tissue Engineering

In recent years, many promising nanotechnological approaches to biomedical research have been developed in order to increase implementation of regenerative medicine and tissue engineering in clinical practice. In the meantime, the use of nanomaterials for the regeneration of diseased or injured tissues is considered advantageous in most areas of medicine. In particular, for the treatment of cardiovascular, osteochondral and neurological defects, but also for the recovery of functions of other organs such as kidney, liver, pancreas, bladder, urethra and for wound healing, nanomaterials are increasingly being developed that serve as scaffolds, mimic the extracellular matrix and promote adhesion or differentiation of cells. This review focuses on the latest developments in regenerative medicine, in which iron oxide nanoparticles (IONPs) play a crucial role for tissue engineering and cell therapy. IONPs are not only enabling the use of non-invasive observation methods to monitor the therapy, but can also accelerate and enhance regeneration, either thanks to their inherent magnetic properties or by functionalization with bioactive or therapeutic compounds, such as drugs, enzymes and growth factors. In addition, the presence of magnetic fields can direct IONP-labeled cells specifically to the site of action or induce cell differentiation into a specific cell type through mechanotransduction.

Interaction between Filler and Polymeric Matrix in Nanocomposites: Magnetic Approach and Applications

In recent years, polymer nanocomposites produced by combining nanofillers and a polymeric matrix are emerging as interesting materials. Polymeric composites have a wide range of applications due to the outstanding and enhanced properties that are obtained thanks to the introduction of nanoparticles. Therefore, understanding the filler-matrix relationship is an important factor in the continued growth of this scientific area and the development of new materials with desired properties and specific applications. Due to their performance in response to a magnetic field magnetic nanocomposites represent an important class of functional nanocomposites. Due to their properties, magnetic nanocomposites have found numerous applications in biomedical applications such as drug delivery, theranostics, etc. This article aims to provide an overview of the filler-polymeric matrix relationship, with a special focus on magnetic nanocomposites and their potential applications in the biomedical field.

Synthesis and ex vivo evaluation of PLGA chitosan surface modulated double walled transdermal Pluronic nanogel for the controlled delivery of Temozolomide

A surface modulated biodegradable transdermal strategy has been exploited for improving the biopharmaceutical properties of Temozolomide augmented in Poly Lactic-co-glycolic acid (PLGA) chitosan double walled nanogel (PCNGL). The PCNGL was synthesized by dual approach methodology showing consistent nanosize particle range of 210 nm and PDI 0.325 ± 0.43 with cationic zeta potential values +29.34 ± 0.79 mV. The PCNGL showed qualitative endothermic & exothermic temperature dependent degradation peaks by thermogravimetry analysis. Blood hemolysis and coagulation assay showed 3.37 ± 0.19 as hemolytic ratio, validating biologically safe margin for transdermal delivery. The in vitro drug release showed 85% transdermal release at slightly acidic pH mimicking skin microenvironment. The ex vivo studies displayed noteworthy penetration potential validated by concentration depth assay and confocal laser scanning microscopy, exhibiting 80% Temozolomide uptake in porcine epidermal tissue. The current research demonstrated the biodegradable controlled delivery of chemotherapeutic Temozolomide leading to biologically safe transdermal therapy.

Peptide-based supramolecular hydrogels for local drug delivery

Peptide-based supramolecular hydrogels have shown great promise as drug delivery systems (DDSs) because of their excellent biocompatibility, biodegradability, biological function, synthetic feasibility, and responsiveness to external stimuli. Self-assembling peptide molecules are able rationally designed into specific nanoarchitectures in response to the different environmental factors under different circumstances. Among all stimuli that have been investigated, utilizing inherent biological microenvironment, such as metal ions, enzymes and endogenous redox species, to trigger self-assembly endows such systems spatiotemporal controllability to transport therapeutics more accurately. Materials formed by weak non-covalent interactions result in the shear-thinning and immediate recovery behavior. Thus, they are injectable via a syringe or catheter, making them the ideal vehicles to deliver drugs. Based on the above merits, self-assembling peptide-based DDSs have been applied to treat various diseases via direct administration at the lesion site. Herein, in this review, we outline the triggers for inducing peptide-based hydrogels formation and serving as DDSs. We also described the advancements of peptide-based supramolecular hydrogels for local drug delivery, including intratumoral, subcutaneous, ischemia-related tissue (intramyocardial, intrarenal, and ischemic hind limb), and ocular administration. Finally, we give a brief perspective about the prospects and challenges in this field.

Biocompatibility, uptake and subcellular localization of bacterial magnetosomes in mammalian cells

Magnetosomes represent biogenic, magnetic nanoparticles biosynthesized by magnetotactic bacteria. Subtle biological control on each step of biomineralization generates core-shell nanoparticles of high crystallinity, strong magnetization and uniform shape and size. These features make magnetosomes a promising alternative to chemically synthesized nanoparticles for many applications in the biotechnological and biomedical field, such as their usage as biosensors in medical diagnostics, as drug-delivery agents, or as contrast agents for magnetic imaging techniques. Thereby, the particles are directly applied to mammalian cells or even injected into the body. In the present work, we provide a comprehensive characterization of isolated magnetosomes as potential cytotoxic effects and particle uptake have not been well studied so far. Different cell lines including cancer cells and primary cells are incubated with increasing particle amounts, and effects on cell viability are investigated. Obtained data suggest a concentration-dependent biocompatibility of isolated magnetosomes for all tested cell lines. Furthermore, magnetosome accumulation in endolysosomal structures around the nuclei is observed. Proliferation rates are affected in the presence of increasing particle amounts; however, viability is not affected and doubling times can be restored by reducing the magnetosome concentration. In addition, we evidence magnetosome-cell interactions that are strong enough to allow for magnetic cell sorting. Overall, our study not only assesses the biocompatibility of isolated magnetosomes, but also evaluates effects on cell proliferation and the fate of internalized magnetosomes, thereby providing prerequisites for their future in vivo application as biomedical agents.

Resveratrol-Loaded Lipid-Core Nanocapsules Modulate Acute Lung Inflammation and Oxidative Imbalance Induced by LPS in Mice

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are inflammatory and oxidative imbalance lung conditions with no successful pharmacological therapy and a high mortality rate. Resveratrol (RSV) is a plant-derived stilbene that presents anti-inflammatory and antioxidant effects. However, its therapeutic application remains limited due to its poor bioavailability, which can be solved by the use of nanocarriers. Previously, we demonstrated that nanoencapsulated RSV (RSV-LNC) pre-treatment, performed 4 h before lipopolysaccharide (LPS) stimulation in mice, increased its anti-inflammatory properties. In this study, we evaluated the anti-inflammatory and antioxidant effects, and lung distribution of RSV-LNCs administered therapeutically (6 h post LPS exposure) in a lung injury mouse model. The results showed that RSV-LNCs posttreatment improved lung function and diminished pulmonary inflammation. Moreover, RSV-LNC treatment enhanced the antioxidant catalase level together with a decrease in the oxidative biomarker in mouse lungs, which was accompanied by an increase in pulmonary Nrf2 antioxidant expression. Finally, the presence of RSV in lung tissue was significantly detected when mice received RSV-LNCs but not when they received RSV in its free form. Together, our results confirm that RSV nanoencapsulation promotes an increase in RSV bioavailability, enhancing its therapeutic effects in an LPS-induced lung injury model.

Comparative Study of Specific Loss Power and Transverse Relaxivity of Spinel Ferrite Nanoensembles Coated With Chitosan and Polyethylene Glycol

We synthesized spinel ferrite nanoensembles (MnFe2O4, CoFe2O4, and Fe3O4) using the chemical co-precipitation method and characterized their physical, chemical, and magnetic properties by X-ray diffraction (XRD), transmission electron microscopy (TEM), physical properties measurement system (PPMS), Mössbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and Raman spectroscopy. Their relaxation properties and potential for hyperthermia therapy were determined using nuclear magnetic resonance (NMR) and cell viability assay, respectively. XRD and TEM data confirmed that the particle core sizes were 6–9 nm before coating while their sizes increased to 10–14 nm and 14–20 nm after coating with chitosan and polyethylene glycol (PEG), respectively. Mössbauer spectroscopy showed superparamagnetic behavior for MnFe2O4 nanoparticles and ferrimagnetic behavior for the CoFe2O4 and Fe3O4 nanoparticles. A detailed studies of MH loops of all three ferrites before and after coating showed surface functionalization by a large reduction of coercivity and anisotropy. The successful coating was further confirmed by the peak shifts in the FTIR spectra of the particles whereas Raman spectra of coated ferrites also displayed the characteristic absorption patterns and suppression of the ferrite peaks suggesting successful coating. The induced heating profile of the nanoparticles in stable suspension was tested with a radio frequency magnetic field of 76 mT and a frequency of 400 kHz. High mortality (>98%) of 9 L gliosarcoma cancer cells by hyperthermia suggested that these nanoparticles could be used for cancer therapy. Transverse relaxivities (r2) determined by NMR for chitosan-coated MnFe2O4, CoFe2O4, and Fe3O4 nanoparticles were 297 (±22), 353 (±26), and 345 (±13), mM−1S−1, while for PEG-coated nanoparticles are 165 (±22), 146 (±14), and 159 (±07) mM−1S−1, respectively. Overall these spinel ferrite nanoensembles show great promise for cancer theranostics research applications.

Thermal Traits of MNPs under High-Frequency Magnetic Fields: Disentangling the Effect of Size and Coating

We investigated the heating abilities of magnetic nanoparticles (MNPs) in a high-frequency magnetic field (MF) as a function of surface coating and size. The cobalt ferrite MNPs were obtained by a hydrothermal method in a water–oleic acid–ethanol system, yielding MNPs with mean diameter of about 5 nm, functionalized with the oleic acid. By applying another cycle of hydrothermal synthesis, we obtained MNPs with about one nm larger diameter. In the next step, the oleic acid was exchanged for 11-maleimidoundecanoic acid or 11-(furfurylureido)undecanoic acid. For the heating experiments, all samples were dispersed in the same solvent (dichloroethane) in the same concentration and the heating performance was studied in a broad interval of MF frequencies (346–782 kHz). The obtained results enabled us to disentangle the impact of the hydrodynamic, structural, and magnetic parameters on the overall heating capabilities. We also demonstrated that the specific power absorption does not show a monotonous trend within the series in the investigated interval of temperatures, pointing to temperature-dependent competition of the Brownian and Néel contributions in heat release.

APTES monolayer coverage on self-assembled magnetic nanospheres for controlled release of anticancer drug Nintedanib

The use of an appropriate delivery system capable of protecting, translocating, and selectively releasing therapeutic moieties to desired sites can promote the efficacy of an active compound. In this work, we have developed a nanoformulation which preserves its magnetization to load a model anticancerous drug and to explore the controlled release of the drug in a cancerous environment. For the preparation of the nanoformulation, self-assembled magnetic nanospheres (MNS) made of superparamagnetic iron oxide nanoparticles were grafted with a monolayer of (3-aminopropyl)triethoxysilane (APTES). A direct functionalization strategy was used to avoid the loss of the MNS magnetization. The successful preparation of the nanoformulation was validated by structural, microstructural, and magnetic investigations. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were used to establish the presence of APTES on the MNS surface. The amine content quantified by a ninhydrin assay revealed the monolayer coverage of APTES over MNS. The monolayer coverage of APTES reduced only negligibly the saturation magnetization from 77 emu/g (for MNS) to 74 emu/g (for MNS-APTES). Detailed investigations of the thermoremanent magnetization were carried out to assess the superparamagnetism in the MNS. To make the nanoformulation pH-responsive, the anticancerous drug Nintedanib (NTD) was conjugated with MNS-APTES through the acid liable imine bond. At pH 5.5, which mimics a cancerous environment, a controlled release of 85% in 48 h was observed. On the other hand, prolonged release of NTD was found at physiological conditions (i.e., pH 7.4). In vitro cytotoxicity study showed dose-dependent activity of MNS-APTES-NTD for human lung cancer cells L-132. About 75% reduction in cellular viability for a 100 μg/mL concentration of nanoformulation was observed. The nanoformulation designed using MNS and monolayer coverage of APTES has potential in cancer therapy as well as in other nanobiological applications.

Stimuli-Responsive Iron Oxide Nanotheranostics: A Versatile and Powerful Approach for Cancer Therapy

Recent advancements in unravelling elements of cancer biology involved in disease progression and treatment resistance have highlighted the need for a holistic approach to effectively tackle cancer. Stimuli-responsive nanotheranostics based on iron oxide nanoparticles are an emerging class of versatile nanomedicines with powerful capabilities to "seek, sense, and attack" multiple components of solid tumors. In this work, the rationale for using iron oxide nanoparticles and the basic physical principles that impact their function in biomedical applications are reviewed. Subsequently, recent advances in the integration of iron oxide nanoparticles with various stimulus mechanisms to facilitate the development of stimuli-responsive nanotheranostics for application in cancer therapy are summarized. The integration of an iron oxide core with various surface coating mechanisms results in the generation of hybrid nanoconstructs with capabilities to codeliver a wide variety of highly potent anticancer therapeutics and immune modulators. Finally, emerging future directions and considerations for their clinical translation are touched upon.

Improvement of Magnetic Particle Hyperthermia: Healthy Tissues Sparing by Reduction in Eddy Currents

Attenuation of the unwanted heating of normal tissues due to eddy currents presents a major challenge in magnetic particle hyperthermia for cancer treatment. Eddy currents are a direct consequence of the applied alternating magnetic field, which is used to excite the nanoparticles in the tumor and have been shown to limit treatment efficacy in clinical trials. To overcome these challenges, this paper presents simple, clinically applicable, numerical approaches which reduce the temperature increase due to eddy currents in normal tissue and simultaneously retain magnetic nanoparticles heating efficiency within the tumor. More specifically, two protocols are examined which involve moving the heating source, an electromagnetic coil, relative to a tumor-bearing phantom tissue during the exposure. In the first protocol, the linear motion of the coil on one side with respect to the hypothesized tumor location inside the phantom is simulated. The estimated maximum temperature increase in the healthy tissue and tumor is reduced by 12% and 9%, respectively, compared to a non-moving coil, which is the control protocol. The second technique involves a symmetrical variation of the first one, where the coil is moving left and right of the phantom in a bidirectional fashion. This protocol is considered as the optimum one, since the estimated maximum temperature rise of the healthy tissue and tumor is reduced by 25% and 1%, respectively, compared to the control protocol. Thus, the advantages of a linearly moving coil are assessed through tissue sparing, rendering this technique suitable for magnetic particle hyperthermia treatment.

Cadmium selenide (CdSe) quantum dots cause genotoxicity and oxidative stress in Allium cepa plants

Quantum Dots (QDs), are considered as promising tools for biomedical applications. They have potential applications in agricultural industries, novel pesticide formulations, use in bio-labels and devices to aid genetic manipulation and post-harvest management. Since interactions with higher plants are of important environmental and ecological concern we investigated the cytotoxicity and genotoxicity of CdSe QDs in a model plant (Allium cepa) and established relationships between QDs genotoxic activity and oxidative stress. Allium cepa bulbs with intact roots were exposed to three concentrations of CdSe QDs (12.5, 25 and 50 nM). Cell viability and mitotic frequencies was measured for cytotoxicity, and to assess the genotoxicity DNA lesions, chromosome aberrations and micronuclei were evaluated. We report that QDs exerted significant genotoxic effects, associated with oxidative stress. This could be correlated with the retention of Cd in Allium roots as a dose-dependent increase with the highest uptake at 50 nM of CdSe QD. Oxidative stress induced by CdSe QD treatment activated both, antioxidant (SOD, CAT) scavengers and antioxidant (GPOD, GSH) enzymes. Concentrations as low as 25 nM CdSe QDs were cytotoxic and 50 nM CdSe QDs was found to be genotoxic to the plant. These findings enable to determine the concentrations to be used when practical applications using nanodevices of this type on plants are being considered.

The Use of Alternative Strategies for Enhanced Nanoparticle Delivery to Solid Tumors

Nanomaterial (NM) delivery to solid tumors has been the focus of intense research for over a decade. Classically, scientists have tried to improve NM delivery by employing passive or active targeting strategies, making use of the so-called enhanced permeability and retention (EPR) effect. This phenomenon is made possible due to the leaky tumor vasculature through which NMs can leave the bloodstream, traverse through the gaps in the endothelial lining of the vessels, and enter the tumor. Recent studies have shown that despite many efforts to employ the EPR effect, this process remains very poor. Furthermore, the role of the EPR effect has been called into question, where it has been suggested that NMs enter the tumor via active mechanisms and not through the endothelial gaps. In this review, we provide a short overview of the EPR and mechanisms to enhance it, after which we focus on alternative delivery strategies that do not solely rely on EPR in itself but can offer interesting pharmacological, physical, and biological solutions for enhanced delivery. We discuss the strengths and shortcomings of these different strategies and suggest combinatorial approaches as the ideal path forward.

Effect of engineered superparamagnetic iron oxide nanoparticles in targeted cardiac precursor cell delivery by MRI

A scientific approach is presented describing the fabrication of nanoprobe (GloTrack) that can act as cardiac precursor label to segregate cells from cardiac/non cardiac origins and traced by magnetic resonance imaging (MRI). Signal regulatory protein alpha (SIRPA) and kinase domain receptor (KDR) recognizing antibodies, form a layer on super paramagnetic iron oxide nanoparticle - poly-ethylene glycol (SPION-PEG) complex, and bind to protein expressed on the surface of cardiac muscle cells. Physical attributes size, distribution, labelling efficiency, echocardiogram (ECG) changes and bio-distribution by MRI were analysed. The results indicate that GloTrack has an average size of 471 nm, exhibits negative potential and promotes labelling efficiency. The bio-distribution of GloTrack in in vivo experiments was traceable in 7T MRI showing high accumulation of GloTrack in cardiac muscles as compared to the liver and spleen. ECG data revealed that GloTrack segregated cardiac precursors has the potential benefit in treating heart failure, thereby paving way in the development of minimal cell manipulation with targeted cell delivery approaches.

Charging Organic Liquids by Static Charge

Aqueous liquids can be charged effectively by a number of methods for many important applications. Organic liquids, however, cannot be charged effectively by existing methods due to their low conductivities, especially the insulating nonpolar organic liquids; hence, there has not been any significant application developed based on charged organic liquids. This study describes an effective fundamental strategy for charging organic liquids, including nonpolar organic liquids: static charge is simply mixed into the liquid. Analyses suggested that the charged species are molecular ions that reside in the bulk of the liquid after charging. This method is simple and general, and the amount and polarity of charge can be flexibly tunable. The effectiveness of this method gives rise to opportunities for the development of novel applications. Charged organic droplets are manipulated for the first time by an electric field for controlling organic reactions. Particles with charge embedded in their bulk matrices are fabricated for the first time (i.e., via polymerizing the liquid monomers mixed with static charge). The charge in this novel class of bulk-charged particles is stable and permanent, especially when compared to the typical surface-charged particles. Simultaneous bulk-charged and bulk-magnetic particles are fabricated for the first time via simply mixing both the static charge and magnetic nanoparticles into the liquid monomers. These highly versatile particles are responsive to both electric and magnetic fields for practical applications.

Studies of nanoparticle delivery with in vitro bio-engineered microtissues

A variety of engineered nanoparticles, including lipid nanoparticles, polymer nanoparticles, gold nanoparticles, and biomimetic nanoparticles, have been studied as delivery vehicles for biomedical applications. When assessing the efficacy of a nanoparticle-based delivery system, in vitro testing with a model delivery system is crucial because it allows for real-time, in situ quantitative transport analysis, which is often difficult with in vivo animal models. The advent of tissue engineering has offered methods to create experimental models that can closely mimic the 3D microenvironment in the human body. This review paper overviews the types of nanoparticle vehicles, their application areas, and the design strategies to improve delivery efficiency, followed by the uses of engineered microtissues and methods of analysis. In particular, this review highlights studies on multicellular spheroids and other 3D tissue engineering approaches for cancer drug development. The use of bio-engineered tissues can potentially provide low-cost, high-throughput, and quantitative experimental platforms for the development of nanoparticle-based delivery systems.

Polymer Nanocomposite-based Coatings for Corrosion Protection

Corrosion of metals induces enormous loss of material performance and increase of cost, which has been a common and intractable issue that needs to be addressed urgently. Coating technology has been acknowledged to be the most economic and efficient approach to retard the metal corrosion. For several decades, polymers have been recognized as an effective anticorrosion coating material in both industries and scientific communities, as they demonstrate good barrier properties, ease of altering properties and massive production. Nanomaterials show distinctively different physical and chemical properties compared with their bulk counterparts, which have been considered as highly promising functional materials in various applications, impacting virtually all the fields of science and technologies. Recently, the introduction of nanomaterials with various properties into polymer matrix to form a polymer nanocomposite has been devoted to improve anticorrosive ability of polymer coatings. In this review article, we highlight the recent advances and synopsis of these high-performance polymer nanocomposites as anticorrosive coating materials. We expect that this work could be helpful for the researchers who are interested in the development of functional nanomaterials and advanced corrosion protection technology.

Preparation, characterization and in vitro antitumor activity evaluation of hyaluronic acid-alendronate-methotrexate nanoparticles

As an anti-metabolic drug, methotrexate (MTX) plays an important role in the treatment of various malignant tumors. However, several side effects such as low selectivity and high toxic of MTX limited its further applications. With aims to increase its accumulation in the tumor sites and reduce the toxicity of normal tissue nonspecific uptake, a self-assembled hyaluronic acid-alendronate-methotrexate nanoparticle (HA-ALN-MTX NPs) with a dual-tumor-targeted drug loaded system was designed and synthesized with an average particle size of 265.6 ± 13.3 nm. The advantage of this nanosystem is that the anticancer drug MTX can be used as a tumor-targeted ligand for folate acid receptors (FA), and hyaluronic acid (HA) can be used as another tumor targeted ligand for CD44 receptors. In vitro experiments confirmed that HA-ALN-MTX NPs has lower toxic effect on normal tissue cells HUVECs and has relatively high proliferation inhibition effect on tumor cells A549. Moreover, the inhibition effect could be adjusted by altering the dose of given drugs. All these results revealed that the prepared HA-ALN-MTX NPs could be selectively taken up by tumor cells by FA and CD44 receptor-mediated endocytosis. Therefore, self-assembled HA-ALN-MTX NPs targeted by these FA/CD44 receptors for anticancer drugs could act as effective antitumor drugs.

Rapid Assembly and Screening of Multivalent Immune Cell-Redirecting Therapies for Leukemia

Therapies that bind with immune cells and redirect their cytotoxic activity toward diseased cells represent a promising and versatile approach to immunotherapy with applications in cancer, lupus, and other diseases; traditional methods for discovering these therapies, however, are often time-intensive and lack the throughput of related target-based discovery approaches. Inspired by the observation that the cytokine, IL-12, can enhance antileukemic activity of the clinically approved T cell redirecting therapy, blinatumomab, here we describe the structure and assembly of a chimeric immune cell-redirecting agent which redirects the lytic activity of primary human T cells toward leukemic B cells and simultaneously cotargets the delivery of T cell-stimulating IL-12. We further describe a novel method for the parallel assembly of compositionally diverse libraries of these bispecific T cell engaging cytokines (BiTEokines) and their high-throughput phenotypic screening, requiring just days for hit identification and the analysis of composition-function relationships. Using this approach, we identified CD19 × CD3 × IL12 compounds that exhibit ex vivo lytic activity comparable to current FDA-approved therapies for leukemia and correlated drug treatment with specific cell–cell contact, cytokine delivery, and leukemia cell lysis. Given the modular nature of these multivalent compounds and their rapid assembly/screening, we anticipate facile extension of this therapeutic approach to a wide range of immune cells, diseased cells, and soluble protein combinations in the future.

Conjugated Photosensitizers for Imaging and PDT in Cancer Research

Early cancer detection and perfect understanding of the disease are imperative toward efficient treatments. It is straightforward that, for choosing a specific cancer treatment methodology, diagnostic agents undertake a critical role. Imaging is an extremely intriguing tool since it assumes a follow up to treatments to survey the accomplishment of the treatment and to recognize any conceivable repeating injuries. It also permits analysis of the disease, as well as to pursue treatment and monitor the possible changes that happen on the tumor. Likewise, it allows screening the adequacy of treatment and visualizing the state of the tumor. Additionally, when the treatment is finished, observing the patient is imperative to evaluate the treatment methodology and adjust the treatment if necessary. The goal of this review is to present an overview of conjugated photosensitizers for imaging and therapy.

Plasmonic Metallic Heteromeric Nanostructures

Binary, ternary, and other high-order plasmonic heteromers possess remarkable physical and chemical properties, enabling them to be used in numerous applications. The seed-mediated approach is one of the most promising and versatile routes to produce plasmonic heteromers. Selective growth of one or multiple domains on desired sites of noble metal, semiconductor, or magnetic seeds would form desired heteromeric nanostructures with multiple functionalities and synergistic effects. In this work, the challenges for the synthetic approaches are discussed with respect to tuning the thermodynamics, as well as the kinetic properties (e.g., pH, temperature, injection rate, among others). Then, plasmonic heteromers with their structure advantages displaying unique activities compared to other hybrid nanostructures (e.g., core-shell, alloy) are highlighted. Some of the main most recent applications of plasmonic heteromers are also presented. Finally, perspectives for further exploitation of plasmonic heteromers are demonstrated. The goal of this work is to provide the current know-how on the synthesis routes of plasmonic heteromers in a summarized manner, so as to achieve a better understanding of the resulting properties and to gain an improved control of their performances and extend their breadth of applications.