Critical design parameters to develop biomimetic organ-on-a-chip models for the evaluation of the safety and efficacy of nanoparticles

Targeted Cancer Therapy-on-A-Chip

Targeted cancer therapy (TCT) is gaining increased interest because it reduces the risks of adverse side effects by specifically treating tumor cells. TCT testing has traditionally been performed using two-dimensional (2D) cell culture and animal studies. Organ-on-a-chip (OoC) platforms have been developed to recapitulate cancer in vitro, as cancer-on-a-chip (CoC), and used for chemotherapeutics development and testing. This review explores the use of CoCs to both develop and test TCTs, with a focus on three main aspects, the use of CoCs to identify target biomarkers for TCT development, the use of CoCs to test free, un-encapsulated TCTs, and the use of CoCs to test encapsulated TCTs. Despite current challenges such as system scaling, and testing externally triggered TCTs, TCToC shows a promising future to serve as a supportive, pre-clinical platform to expedite TCT development and bench-to-bedside translation.

Blood vessel wall shear stress determines regions of liposome accumulation in angiogenic vasculature

Nanoparticles used for drug delivery often require intravenous administration exposing them to fluid forces within the vasculature, yet the impact of blood flow on nanoparticle delivery remains incompletely understood. Here, we utilized transgenic zebrafish embryos to investigate the relationship between the accumulation of fluorescently labeled PEGylated liposomes and various hemodynamic factors (such as flow velocity, wall shear stress (WSS), and flow pattern) across a wide range of angiogenic blood vessels. We reconstructed 3D models of vascular structures from confocal images and used computational fluid dynamics to calculate local WSS, velocities, and define flow patterns. The spatial distribution of fluorescently labeled liposomes was subsequently mapped within the same 3D space and correlated with local hemodynamic parameters. Through the integration of computational fluid dynamics and in vivo experimentation, we show that liposomes accumulated in vessel regions with WSS between 0.1-0.8 Pa, displaying an inverse linear correlation (R2 > 0.85) between time-averaged wall shear stress and liposome localization in vivo. Interestingly, flow pattern did not appear to impact liposome accumulation. Collectively, our findings suggest the potential of stealth liposomes for passive targeting of low-flow vasculature, including capillaries and intricate angiogenic vasculature resembling that of tumor vessel networks.

A microphysiological system for handling graphene related materials under flow conditions

The field of nanotechnology has developed rapidly in recent decades due to its broad applications in many industrial and biomedical fields. Notably, 2D materials such as graphene-related materials (GRMs) have been extensively explored and, as such, their safety needs to be assessed. However, GRMs tend to deposit quickly, present low stability in aqueous solutions, and adsorb to plastic materials. Consequently, traditional approaches based on static assays facilitate their deposition and adsorption and fail to recreate human physiological conditions. Organ-on-a-chip (OOC) technology could, however, solve these drawbacks and lead to the development of microphysiological systems (MPSs) that mimic the microenvironment present in human tissues. In light of the above, in the present study a microfluidic system under flow conditions has been optimised to minimise graphene oxide (GO) and few-layer graphene (FLG) adsorption and deposition. For that purpose, a kidney-on-a-chip was developed and optimised to evaluate the effects of exposure to GO and FLG flakes at a sublethal dose under fluid flow conditions. In summary, MPSs are an innovative and precise tool for evaluating the effects of exposure to GRMs and other type of nanomaterials.

Magnetic nanoparticles fabricated/integrated with microfluidics for biological applications: A review

Nanostructured materials have gained significant attention in recent years for their potential in biological applications, such as cell and biomolecular sorting, as well as early detection of metastatic cancer. Among these materials, magnetic nanoparticles (MNPs) stand out for their easy functionalization, high specific surface area, chemical stability, and superparamagnetic properties. However, conventional fabrication methods can lead to inconsistencies in MNPs' characteristics and performance, highlighting the need for a cost-effective, controllable, and reproducible synthesis approach. In this review, we will discuss the utilization of microfluidic technology as a cutting-edge strategy for the continuous and regulated synthesis of MNPs. This approach has proven effective in producing MNPs with a superior biomedical performance by offering precise control over particle size, shape, and surface properties. We will examine the latest research findings on developing and integrating MNPs synthesized through continuous microfluidic processes for a wide range of biological applications. By providing an overview of the current state of the field, this review aims to showcase the advantages of microfluidics in the fabrication and integration of MNPs, emphasizing their potential to revolutionize diagnostic and therapeutic methods within the realm of biotechnology.

Doxorubicin-mediated cardiac dysfunction: Revisiting molecular interactions, pharmacological compounds and (nano)theranostic platforms

Although chemotherapy drugs are extensively utilized in cancer therapy, their administration for treatment of patients has faced problems that regardless of chemoresistance, increasing evidence has shown concentration-related toxicity of drugs. Doxorubicin (DOX) is a drug used in treatment of solid and hematological tumors, and its function is based on topoisomerase suppression to impair cancer progression. However, DOX can also affect the other organs of body and after chemotherapy, life quality of cancer patients decreases due to the side effects. Heart is one of the vital organs of body that is significantly affected by DOX during cancer chemotherapy, and this can lead to cardiac dysfunction and predispose to development of cardiovascular diseases and atherosclerosis, among others. The exposure to DOX can stimulate apoptosis and sometimes, pro-survival autophagy stimulation can ameliorate this condition. Moreover, DOX-mediated ferroptosis impairs proper function of heart and by increasing oxidative stress and inflammation, DOX causes cardiac dysfunction. The function of DOX in mediating cardiac toxicity is mediated by several pathways that some of them demonstrate protective function including Nrf2. Therefore, if expression level of such protective mechanisms increases, they can alleviate DOX-mediated cardiac toxicity. For this purpose, pharmacological compounds and therapeutic drugs in preventing DOX-mediated cardiotoxicity have been utilized and they can reduce side effects of DOX to prevent development of cardiovascular diseases in patients underwent chemotherapy. Furthermore, (nano)platforms are used comprehensively in treatment of cardiovascular diseases and using them for DOX delivery can reduce side effects by decreasing concentration of drug. Moreover, when DOX is loaded on nanoparticles, it is delivered into cells in a targeted way and its accumulation in healthy organs is prevented to diminish its adverse impacts. Hence, current paper provides a comprehensive discussion of DOX-mediated toxicity and subsequent alleviation by drugs and nanotherapeutics in treatment of cardiovascular diseases.

Implications of biomimetic nanocarriers in targeted drug delivery

Nanomaterials and nanostructures have shown fascinating performances in various biomedicine fields, from cosmetic to cancer diagnosis and therapy. Engineered nanomaterials can encapsulate both lipophilic and hydrophilic substances/drugs to eliminate their limitations in the free forms, such as low bioavailability, multiple drug administration, off-target effects, and various side effects. Moreover, it is possible to deliver the loaded cargo to the desired site of action using engineered nanomaterials. One approach that has made nanocarriers more sophisticated is the "biomimetic" concept. In this scenario, biomolecules (e.g., natural proteins, peptides, phospholipids, cell membranes) are used as building blocks to construct nanocarriers and/or modify agents. For instance, it has been reported that specific cells tend to migrate to a particular site during specific circumstances (e.g., inflammation, tumor formation). Employing the cell membrane of these cells as a coating for nanocarriers confers practical targeting approaches. Accordingly, we introduce the biomimetic concept in the current study, review the recent studies, challenge the issues, and provide practical solutions.