Trends towards Biomimicry in Theranostics

Selective adsorption of Hg(ii) with diatomite-based mesoporous materials functionalized by pyrrole-thiophene copolymers: condition optimization, application and mechanism

A novel diatomite-based mesoporous material of MCM-41/co-(PPy-Tp) was prepared with MCM-41 as carrier and functionalized with the copolymer of pyrrole and thiophene. The physicochemical characteristics of the as-prepared materials were characterized by various characterization means. The removal behaviour of Hg(ii) was adequately investigated via series of single factor experiments and some vital influence factors were optimized via response surface methodology method. The results exhibit that diatomite-based materials MCM-41/co-(PPy-Tp) has an optimal adsorption capability of 537.15 mg g-1 towards Hg(ii) at pH = 7.1. The removal process of Hg(ii) onto MCM-41/co-(PPy-Tp) is controlled by monolayer chemisorption based on the fitting results of pseudo-second-order kinetic and Langmuir models. In addition, the adsorption of Hg(ii) ions onto MCM-41/co-(PPy-Tp) is mainly completed through forming a stable complex with N or S atoms in MCM-41/co-(PPy-Tp) by electrostatic attraction and chelation. The as-developed MCM-41/co-(PPy-Tp) displays excellent recyclability and stabilization, has obviously selective adsorption for Hg(ii) in the treatment of actual electroplating wastewater. Diatomite-based mesoporous material functionalized by the copolymer of pyrrole and thiophene exhibits promising application prospect.

Anticancer Nanotherapeutics in Clinical Trials: The Work behind Clinical Translation of Nanomedicine

The ultimate goal of nanomedicine has always been the generation of translational technologies that can ameliorate current therapies. Cancer disease represented the primary target of nanotechnology applied to medicine, since its clinical management is characterized by very toxic therapeutics. In this effort, nanomedicine showed the potential to improve the targeting of different drugs by improving their pharmacokinetics properties and to provide the means to generate new concept of treatments based on physical treatments and biologics. In this review, we considered different platforms that reached the clinical trial investigation, providing an objective analysis about their physical and chemical properties and the working mechanism at the basis of their tumoritr opic properties. With this review, we aim to help other scientists in the field in conceiving their delivering platforms for clinical translation by providing solid examples of technologies that eventually were tested and sometimes approved for human therapy.

New anti-cancer explorations based on metal ions

Due to the urgent demand for more anti-cancer methods, the new applications of metal ions in cancer have attracted increasing attention. Especially the three kinds of the new mode of cell death, including ferroptosis, calcicoptosis, and cuproptosis, are of great concern. Meanwhile, many metal ions have been found to induce cell death through different approaches, such as interfering with osmotic pressure, triggering biocatalysis, activating immune pathways, and generating the prooxidant effect. Therefore, varieties of new strategies based on the above approaches have been studied and applied for anti-cancer applications. Moreover, many contrast agents based on metal ions have gradually become the core components of the bioimaging technologies, such as MRI, CT, and fluorescence imaging, which exhibit guiding significance for cancer diagnosis. Besides, the new nano-theranostic platforms based on metal ions have experimentally shown efficient response to endogenous and exogenous stimuli, which realizes simultaneous cancer therapy and diagnosis through a more controlled nano-system. However, most metal-based agents have still been in the early stages, and controlled clinical trials are necessary to confirm or not the current expectations. This article will focus on these new explorations based on metal ions, hoping to provide some theoretical support for more anti-cancer ideas.

Recent advances in targeted drug delivery systems for resistant colorectal cancer

Colorectal cancer (CRC) is one of the deadliest cancers in the world, the incidences and morality rate are rising and poses an important threat to the public health. It is known that multiple drug resistance (MDR) is one of the major obstacles in CRC treatment. Tumor microenvironment plus genomic instability, tumor derived exosomes (TDE), cancer stem cells (CSCs), circulating tumor cells (CTCs), cell-free DNA (cfDNA), as well as cellular signaling pathways are important issues regarding resistance. Since non-targeted therapy causes toxicity, diverse side effects, and undesired efficacy, targeted therapy with contribution of various carriers has been developed to address the mentioned shortcomings. In this paper the underlying causes of MDR and then various targeting strategies including exosomes, liposomes, hydrogels, cell-based carriers and theranostics which are utilized to overcome therapeutic resistance will be described. We also discuss implication of emerging approaches involving single cell approaches and computer-aided drug delivery with high potential for meeting CRC medical needs.

Water-Soluble Silicon Quantum Dots toward Fluorescence-Guided Photothermal Nanotherapy

We report carboxy-terminated silicon quantum dots (SiQDs) that exhibit high solubility in water due to the high molecular coverage of surface monolayers, bright light emission with high photoluminescence quantum yields (PLQYs), long-term stability in the PL property for monitoring cells, less toxicity to the cells, and a high photothermal response. We prepared water-soluble SiQDs by the thermal hydrosilylation of 10-undecenoic acid on their hydrogen-terminated surfaces, provided by the thermal disproportionation of triethoxysilane hydrolyzed at pH 3 and subsequent hydrofluoric etching. The 10-undecanoic acid-functionalized SiQDs (UA:SiQDs) showed long-term stability in hydrophilic solvents including ethanol and water (pH 7). We assess their interaction with live cells by means of cellular uptake, short-term toxicity, and, for the first time, long-term cytotoxicity. Results show that UA:SiQDs are potential candidates for theranostics, with their good optical properties enabling imaging for more than 18 days and a photothermal response having a 25.1% photothermal conversion efficiency together with the direct evidence of cell death by laser irradiation. UA:SiQDs have low cytotoxicity with full viability of up to 400 μg/mL for the short term and a 50% cell viability value after 14 days of incubation at a 50 μg/mL concentration.

Humanized Biomimetic Nanovesicles for Neuron Targeting

Nanovesicles (NVs) are emerging as innovative, theranostic tools for cargo delivery. Recently, surface engineering of NVs with membrane proteins from specific cell types has been shown to improve the biocompatibility of NVs and enable the integration of functional attributes. However, this type of biomimetic approach has not yet been explored using human neural cells for applications within the nervous system. Here, this paper optimizes and validates the scalable and reproducible production of two types of neuron-targeting NVs, each with a distinct lipid formulation backbone suited to potential therapeutic cargo, by integrating membrane proteins that are unbiasedly sourced from human pluripotent stem-cell-derived neurons. The results establish that both endogenous and genetically engineered cell-derived proteins effectively transfer to NVs without disruption of their physicochemical properties. NVs with neuron-derived membrane proteins exhibit enhanced neuronal association and uptake compared to bare NVs. Viability of 3D neural sphere cultures is not disrupted by treatment, which verifies the utility of organoid-based approaches as NV testing platforms. Finally, these results confirm cellular association and uptake of the biomimetic humanized NVs to neurons within rodent cranial nerves. In summary, the customizable NVs reported here enable next-generation functionalized theranostics aimed to promote neuroregeneration.

Recent Advances in Understanding the Protein Corona of Nanoparticles and in the Formulation of "Stealthy" Nanomaterials

In the last decades, the staggering progress in nanotechnology brought around a wide and heterogeneous range of nanoparticle-based platforms for the diagnosis and treatment of many diseases. Most of these systems are designed to be administered intravenously. This administration route allows the nanoparticles (NPs) to widely distribute in the body and reach deep organs without invasive techniques. When these nanovectors encounter the biological environment of systemic circulation, a dynamic interplay occurs between the circulating proteins and the NPs, themselves. The set of proteins that bind to the NP surface is referred to as the protein corona (PC). PC has a critical role in making the particles easily recognized by the innate immune system, causing their quick clearance by phagocytic cells located in organs such as the lungs, liver, and spleen. For the same reason, PC defines the immunogenicity of NPs by priming the immune response to them and, ultimately, their immunological toxicity. Furthermore, the protein corona can cause the physical destabilization and agglomeration of particles. These problems induced to consider the PC only as a biological barrier to overcome in order to achieve efficient NP-based targeting. This review will discuss the latest advances in the characterization of PC, development of stealthy NP formulations, as well as the manipulation and employment of PC as an alternative resource for prolonging NP half-life, as well as its use in diagnostic applications.

Nanovectors Design for Theranostic Applications in Colorectal Cancer

Colorectal cancer (CRC) is a diffused disease with limited therapeutic options, none of which are often curative. Based on the molecular markers and targets expressed by the affected tissues, numerous novel approaches have been developed to study and treat this disease. In particular, the field of nanotechnology offers an astonishingly wide array of innovative nanovectors with high versatility and adaptability for both diagnosis and therapy (the so called “theranostic platforms”). However, such complexity can make the selection of a specific nanocarrier model to study a perplexing endeavour for the biomedical scientist or clinician not familiar with this field of inquiry. This review offers a comprehensive overview of this wide body of knowledge, in order to outline the essential requirements for the clinical viability evaluation of a nanovector model in CRC. In particular, the differences among the foremost designs, their specific advantages, and technological caveats will be treated, never forgetting the ultimate endpoint for these systems development: the clinical practice.