Nanoparticles for concurrent multimodality imaging and therapy: the dawn of new theragnostic synergies

Recent Biomedical Applications of Coupling Nanocomposite Polymeric Materials Reinforced with Variable Carbon Nanofillers

The hybridization between polymers and carbon materials is one of the most recent and crucial study areas which abstracted more concern from scientists in the past few years. Polymers could be classified into two classes according to the source materials synthetic and natural. Synthetic polymeric materials have been applied over a floppy zone of industrial fields including the field of biomedicine. Carbon nanomaterials including (fullerene, carbon nanotubes, and graphene) classified as one of the most significant sources of hybrid materials. Nanocarbons are improving significantly mechanical properties of polymers in nanocomposites in addition to physical and chemical properties of the new materials. In all varieties of proposed bio-nanocomposites, a considerable improvement in the microbiological performance of the materials has been explored. Various polymeric materials and carbon-course nanofillers were present, along with antibacterial, antifungal, and anticancer products. This review spots the light on the types of synthetic polymers-based carbon materials and presented state-of-art examples on their application in the area of biomedicine.

Review on Biomedical Advances of Hybrid Nanocomposite Biopolymeric Materials

Hybrid materials are classified as one of the most highly important topics that have been of great interest to many researchers in recent decades. There are many species that can fall under this category, one of the most important of which contain biopolymeric materials as a matrix and are additionally reinforced by different types of carbon sources. Such materials are characterized by many diverse properties in a variety industrial and applied fields but especially in the field of biomedical applications. The biopolymeric materials that fall under this label are divided into natural biopolymers, which include chitosan, cellulose, and gelatin, and industrial or synthetic polymers, which include polycaprolactone, polyurethane, and conducting polymers of variable chemical structures. Furthermore, there are many types of carbon nanomaterials that are used as enhancers in the chemical synthesis of these materials as reinforcement agents, which include carbon nanotubes, graphene, and fullerene. This research investigates natural biopolymers, which can be composed of carbon materials, and the educational and medical applications that have been developed for them in recent years. These applications include tissue engineering, scaffold bones, and drug delivery systems.

Theranostic liposomes as nanodelivered chemotherapeutics enhanced the microwave ablation of hepatocellular carcinoma

Aim: This study aimed to develop indocyanine green- and doxorubicin-loaded liposomes (DILPs) as theranostic nanoplatform for the detection of hepatocellular carcinoma (HCC) and as an efficient chemotherapeutic to enhance microwave ablation. Materials & methods: DILPs were synthesized and thoroughly characterized. Biocompatibility, tumor uptake and accumulation, and synergistic ablation-chemotherapeutic efficiency were systematically explored in them. In addition, human HCC surgical samples were used to test the affinity of DILPs for HCC. Results: The combination of microwave ablation and DILPs enhanced the ablation efficiency of HCC with apparent tumor inhibition. DILPs exhibited excellent diagnostic ability and could detect 2.5-mm HCC lesions via optoacoustic tomography imaging. DILPs had better affinity for human HCC surgical samples compared with normal liver tissue. Conclusion: Theranostic DILPs could serve as promising nanoparticles for treatment and management of HCC in the clinic.

Target induced reconstruction of DNAzymatic amplifier nanomachines in living cells for concurrent imaging and gene silencing

A novel DNAzymatic amplifier nanomachine that enables the functions of concurrent mRNA imaging and gene silencing in living cells has been reported.

PEG-PCL-based nanomedicines: A biodegradable drug delivery system and its application

The lack of efficient therapeutic options for many severe disorders including cancer spurs demand for improved drug delivery technologies. Nanoscale drug delivery systems based on poly(ethylene glycol)-poly(ε-caprolactone) copolymers (PEG-PCL) represent a strategy to implement therapies with enhanced drug accumulation at the site of action and decreased off-target effects. In this review, we discuss state-of-the-art nanomedicines based on PEG-PCL that have been investigated in a preclinical setting. We summarize the various synthesis routes and different preparation methods used for the production of PEG-PCL nanoparticles. Additionally, we review physico-chemical properties including biodegradability, biocompatibility, and drug loading. Finally, we highlight recent therapeutic applications investigated in vitro and in vivo using advanced systems such as triggered release, multi-component therapies, theranostics, or gene delivery systems.

Dual-modality imaging with 99mTc and fluorescent indocyanine green using surface-modified silica nanoparticles for biopsy of the sentinel lymph node: an animal study

Background

We propose a new approach to facilitate sentinel node biopsy examination by multimodality imaging in which radioactive and near-infrared (NIR) fluorescent nanoparticles depict deeply situated sentinel nodes and fluorescent nodes with anatomical resolution in the surgical field. For this purpose, we developed polyamidoamine (PAMAM)-coated silica nanoparticles loaded with technetium-99m (^99mTc) and indocyanine green (ICG).

Methods

We conducted animal studies to test the feasibility and utility of this dual-modality imaging probe. The mean diameter of the PAMAM-coated silica nanoparticles was 30 to 50 nm, as evaluated from the images of transmission electron microscopy and scanning electron microscopy. The combined labeling with ^99mTc and ICG was verified by thin-layer chromatography before each experiment. A volume of 0.1 ml of the nanoparticle solution (7.4 MBq, except for one rat that was injected with 3.7 MBq, and 1 μg of an ICG derivative [ICG-sulfo-OSu]) was injected submucosally into the tongue of six male Wistar rats.

Results

Scintigraphic images showed increased accumulation of ^99mTc in the neck of four of the six rats. Nineteen lymph nodes were identified in the dissected neck of the six rats, and a contact radiographic study showed three nodes with a marked increase in uptake and three nodes with a weak uptake. NIR fluorescence imaging provided real-time clear fluorescent images of the lymph nodes in the neck with anatomical resolution. Six lymph nodes showed weak (+) to strong (+++) fluorescence, whereas other lymph nodes showed no fluorescence. Nodes showing increased radioactivity coincided with the fluorescent nodes. The radioactivity of 15 excised lymph nodes from the four rats was assayed using a gamma well counter. Comparisons of the levels of radioactivity revealed a large difference between the high-fluorescence-intensity group (four lymph nodes; mean, 0.109% ± 0.067%) and the low- or no-fluorescence-intensity group (11 lymph nodes; mean, 0.001% ± 0.000%, p < 0.05). Transmission electron microscopy revealed that small black granules were localized to and dispersed within the cytoplasm of macrophages in the lymph nodes.

Conclusion

Although further studies are needed to determine the appropriate dose of the dual-imaging nanoparticle probe for effective sensitivity and safety, the results of this animal study revealed a novel method for improved node detection by a dual-modality approach for sentinel lymph node biopsy.

Noninvasive detection of complement activation through radiologic imaging

A wealth of experimental and clinical data demonstrates that the complement system is involved in the pathogenesis of numerous inflammatory diseases. Complement activation contributes to injury in disorders that involve nearly every tissue in the body. Concerted effort has been expended in recent years to develop therapeutic complement inhibitors. Eculizumab, an inhibitory antibody to C5, was recently approved for the treatment of several diseases, and many other complement inhibitors are in clinical development. As these drugs are developed, the need for improved methods of detecting and monitoring complement activation within particular tissues will be increasingly important. We have developed a magnetic resonance imaging (MRI)-based method for noninvasive detection of complement activation. This method utilizes iron-oxide nanoparticles that are targeted to sites of complement activation with a recombinant protein that contains the C3d-binding region of complement receptor (CR) 2. Iron-oxide nanoparticles darken (negatively enhance) images obtained by T2-weighted MRI. We have demonstrated that the CR2-targeted nanoparticles bind within the kidneys of mice with lupus-like kidney disease (MRL/1pr mice), causing a decrease in the T2 signal within the kidneys. This method discriminates diseased kidneys from healthy controls, and the magnitude of the negative enhancement in the cortex of MRL/lpr mice correlates with their disease severity. This method may be useful for identifying those patients most likely to benefit from complement inhibitors and for monitoring the response of these patients to treatment. These results may open up new avenues to develop tools for the monitoring of disease progression in complement-dependent diseases.

Photodynamic nanomedicine in the treatment of solid tumors: perspectives and challenges

Photodynamic therapy (PDT) is a promising treatment strategy where activation of photosensitizer drugs with specific wavelengths of light results in energy transfer cascades that ultimately yield cytotoxic reactive oxygen species which can render apoptotic and necrotic cell death. Without light the photosensitizer drugs are minimally toxic and the photoactivating light itself is non-ionizing. Therefore, harnessing this mechanism in tumors provides a safe and novel way to selectively eradicate tumor with reduced systemic toxicity and side effects on healthy tissues. For successful PDT of solid tumors, it is necessary to ensure tumor-selective delivery of the photosensitizers, as well as, the photoactivating light and to establish dosimetric correlation of light and drug parameters to PDT-induced tumor response. To this end, the nanomedicine approach provides a promising way towards enhanced control of photosensitizer biodistribution and tumor-selective delivery. In addition, refinement of nanoparticle designs can also allow incorporation of imaging agents, light delivery components and dosimetric components. This review aims at describing the current state-of-the-art regarding nanomedicine strategies in PDT, with a comprehensive narrative of the research that has been carried out in vitro and in vivo, with a discussion of the nanoformulation design aspects and a perspective on the promise and challenges of PDT regarding successful translation into clinical application.

Uptake and fate of surface modified silica nanoparticles in head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) is currently the eighth leading cause of cancer death worldwide. The often severe side effects, functional impairments and unfavorable cosmetic outcome of conventional therapies for HNSCC have prompted the quest for novel treatment strategies, including the evaluation of nanotechnology to improve e.g. drug delivery and cancer imaging. Although silica nanoparticles hold great promise for biomedical applications, they have not yet been investigated in the context of HNSCC. In the present in-vitro study we thus analyzed the cytotoxicity, uptake and intracellular fate of 200-300 nm core-shell silica nanoparticles encapsulating fluorescent dye tris(bipyridine)ruthenium(II) dichloride with hydroxyl-, aminopropyl- or PEGylated surface modifications (Ru@SiO₂-OH, Ru@SiO₂-NH₂, Ru@SiO₂-PEG) in the human HNSCC cell line UMB-SCC 745.

Results

We found that at concentrations of 0.125 mg/ml, none of the nanoparticles used had a statistically significant effect on proliferation rates of UMB-SCC 745. Confocal and transmission electron microscopy showed an intracellular appearance of Ru@SiO₂-OH and Ru@SiO₂-NH₂ within 30 min. They were internalized both as single nanoparticles (presumably via clathrin-coated pits) or in clusters and always localized to cytoplasmic membrane-bounded vesicles. Immunocytochemical co-localization studies indicated that only a fraction of these nanoparticles were transferred to early endosomes, while the majority accumulated in large organelles. Ru@SiO₂-OH and Ru@SiO₂-NH₂ nanoparticles had never been observed to traffic to the lysosomal compartment and were rather propagated at cell division. Intracellular persistence of Ru@SiO₂-OH and Ru@SiO₂-NH₂ was thus traceable over 5 cell passages, but did not result in apparent changes in cell morphology and vitality. In contrast to Ru@SiO₂-OH and Ru@SiO₂-NH₂ uptake of Ru@SiO₂-PEG was minimal even after 24 h.

Conclusions

Our study is the first to provide evidence that silica-based nanoparticles may serve as useful tools for the development of novel treatment options in HNSCC. Their long intracellular persistence could be of advantage for e.g. chronic therapeutic modalities. However, their complex endocytotic pathways require further investigations.

Multimodal silica nanoparticles are effective cancer-targeted probes in a model of human melanoma

Nanoparticle-based materials, such as drug delivery vehicles and diagnostic probes, currently under evaluation in oncology clinical trials are largely not tumor selective. To be clinically successful, the next generation of nanoparticle agents should be tumor selective, nontoxic, and exhibit favorable targeting and clearance profiles. Developing probes meeting these criteria is challenging, requiring comprehensive in vivo evaluations. Here, we describe our full characterization of an approximately 7-nm diameter multimodal silica nanoparticle, exhibiting what we believe to be a unique combination of structural, optical, and biological properties. This ultrasmall cancer-selective silica particle was recently approved for a first-in-human clinical trial. Optimized for efficient renal clearance, it concurrently achieved specific tumor targeting. Dye-encapsulating particles, surface functionalized with cyclic arginine-glycine-aspartic acid peptide ligands and radioiodine, exhibited high-affinity/avidity binding, favorable tumor-to-blood residence time ratios, and enhanced tumor-selective accumulation in αvβ3 integrin-expressing melanoma xenografts in mice. Further, the sensitive, real-time detection and imaging of lymphatic drainage patterns, particle clearance rates, nodal metastases, and differential tumor burden in a large-animal model of melanoma highlighted the distinct potential advantage of this multimodal platform for staging metastatic disease in the clinical setting.

Imaging and drug delivery using theranostic nanoparticles

Nanoparticle technologies are significantly impacting the development of both therapeutic and diagnostic agents. At the intersection between treatment and diagnosis, interest has grown in combining both paradigms into clinically effective formulations. This concept, recently coined as theranostics, is highly relevant to agents that target molecular biomarkers of disease and is expected to contribute to personalized medicine. Here we review state-of-the-art nanoparticles from a therapeutic and a diagnostic perspective and discuss challenges in bringing these fields together. Major classes of nanoparticles include, drug conjugates and complexes, dendrimers, vesicles, micelles, core-shell particles, microbubbles, and carbon nanotubes. Most of these formulations have been described as carriers of either drugs or contrast agents. To observe these formulations and their interactions with disease, a variety of contrast agents have been used, including optically active small molecules, metals and metal oxides, ultrasonic contrast agents, and radionuclides. The opportunity to rapidly assess and adjust treatment to the needs of the individual offers potential advantages that will spur the development of theranostic agents.

Nanotargeted radionuclides for cancer nuclear imaging and internal radiotherapy

Current progress in nanomedicine has exploited the possibility of designing tumor-targeted nanocarriers being able to deliver radionuclide payloads in a site or molecular selective manner to improve the efficacy and safety of cancer imaging and therapy. Radionuclides of auger electron-, α-, β-, and γ-radiation emitters have been surface-bioconjugated or after-loaded in nanoparticles to improve the efficacy and reduce the toxicity of cancer imaging and therapy in preclinical and clinical studies. This article provides a brief overview of current status of applications, advantages, problems, up-to-date research and development, and future prospects of nanotargeted radionuclides in cancer nuclear imaging and radiotherapy. Passive and active nanotargeting delivery of radionuclides with illustrating examples for tumor imaging and therapy are reviewed and summarized. Research on combing different modes of selective delivery of radionuclides through nanocarriers targeted delivery for tumor imaging and therapy offers the new possibility of large increases in cancer diagnostic efficacy and therapeutic index. However, further efforts and challenges in preclinical and clinical efficacy and toxicity studies are required to translate those advanced technologies to the clinical applications for cancer patients.