Graphene Oxide Hosting a pH-Sensitive Prodrug: An In Silico Investigation of Graphene Oxide-Based Nanovehicle toward Cancer Therapy

Unveiling the drug delivery mechanism of graphene oxide dots at the atomic scale

Graphene oxide (GO) is an amphiphilic and versatile graphene-based nanomaterial that is extremely promising for targeted drug delivery, which aims to administer drugs in a spatially and temporally controlled manner. A typical GO nanocarrier features a polyethylene glycol coating and conjugation to an active targeting ligand. However, it is challenging to accurately model GO dots, because of their intrinsically complex and not unique structure. Here, realistic atomistic GO models are designed as homogeneously/inhomogeneously oxidized flakes and then coated with stealth polymeric chains conjugated to an active targeting ligand (PEG-cRGD). Doxorubicin (DOX) adsorption is investigated by metadynamics simulations for accelerated loading/release events. The presence of PEG and cRGD are found not to affect the DOX adsorption, whereas the homogeneity of oxidation plays a crucial role. We also proved that a change in pH towards acidic conditions causes a reduction in the GO/DOX affinity in line with a pH-triggered release mechanism. Based on this study, the ideal graphene-based DOX carrier is identified as a homogeneously highly oxidized GO where graphitic regions with strong DOX π-π stacking are limited. Such interactions excessively stabilize DOX and are not weakened by a pH-change. On the contrary, DOX interactions with surface oxidized groups are H-bonding and electrostatic, which can effectively be modified by a pH reduction. Our findings are useful to the experimental community to further develop successful drug delivery systems.

Toward the Integration of Machine Learning and Molecular Modeling for Designing Drug Delivery Nanocarriers

The pioneering work on liposomes in the 1960s and subsequent research in controlled drug release systems significantly advances the development of nanocarriers (NCs) for drug delivery. This field is evolved to include a diverse array of nanocarriers such as liposomes, polymeric nanoparticles, dendrimers, and more, each tailored to specific therapeutic applications. Despite significant achievements, the clinical translation of nanocarriers is limited, primarily due to the low efficiency of drug delivery and an incomplete understanding of nanocarrier interactions with biological systems. Addressing these challenges requires interdisciplinary collaboration and a deep understanding of the nano-bio interface. To enhance nanocarrier design, scientists employ both physics-based and data-driven models. Physics-based models provide detailed insights into chemical reactions and interactions at atomic and molecular scales, while data-driven models leverage machine learning to analyze large datasets and uncover hidden mechanisms. The integration of these models presents challenges such as harmonizing different modeling approaches and ensuring model validation and generalization across biological systems. However, this integration is crucial for developing effective and targeted nanocarrier systems. By integrating these approaches with enhanced data infrastructure, explainable AI, computational advances, and machine learning potentials, researchers can develop innovative nanomedicine solutions, ultimately improving therapeutic outcomes.

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.

Radiolabeled florescent-magnetic graphene oxide nanosheets: probing the biodistribution of a potential PET-MRI hybrid imaging agent for detection of fibrosarcoma tumor

PURPOSE

Radiolabeled graphene oxide (GO) nanosheets has been one of the most extensively studied nanoplatform for in vivo radioisotope delivery. Herein, we describe the functionalization of the surface of GO nanosheets with Fe3O4 magnetic nanoparticles, cysteine amino acid as an interface ligand, and cadmium telluride quantum dots.

MATERIALS AND METHODS

To enable In vivo PET imaging, the GO@Fe3O4-cys-CdTe QDs were labeled with 68Ga to yield [68Ga] Ga-Go@ Fe3O4-Cys-CdTe QDs. Furthermore, serum stability tests were performed and the biological behavior of the nanocomposite was evaluated in rats bearing fibrosarcoma tumor.

RESULTS

Liver, blood and tumor were the most accumulated sites at 1 h after the injection, and the radiolabeled nanocomposite as a PET/MRI imaging agent showed fast depletion from body and acceptable tumor uptake.

CONCLUSION

Magnetic (Fe3O4) and fluorescent components (CdTe QDs) along with a positron-emitting radionuclide will help to design a multimodal imaging system (PET/MRI/OI) which will offer the advantages of combined imaging techniques and further possible used in localized radionuclide therapy. Overall, [68Ga] Ga-GO@Fe3O4-cys-CdTe QDs nanocomposite shows great promise as a radiolabeled imaging agent owing to high accumulation in tumor region.

Sustainable Routed Mxene-Based Aminolyzed PU/PCL Film for Increased Oxidative Stress and a pH-Sensitive Drug Delivery System for Anticancer Therapy

A remarkable challenge in the anticancer drug delivery system is developing an implantable system that can improve the chemotherapeutic effect. Polyurethane is an excellent implantable substrate, with flaws in hydrophobicity. We modified polyurethane via the chemical aminolysis technique to enhance the wettability and protein interaction. The created pores can release the rutin complex incorporated in the polyurethane matrix. In this work, the hybrid polymer matrix consists of Mxene synthesized via a sustainable and simple method by introducing a toxic-free MAX phase and etchants. The incorporation of Mxene and PCL can enhance physicochemical and biological compatibility. Sustainable Mxene increases oxidative stress, cell death, and antibacterial activity, which also resulted in the Mxene@APU/PCL film. Meanwhile, the drug release with respect to pH sensitivity was demonstrated in which Mxene and Mxene@APU/PCL films showed the highest release at pH 5.2; this indicates that the prepared Mxene and aminolyzed polyurethane can function according to the biological system and release the drug from the polymer matrix on slow degradation and swellability. The Mxene and Mxene@APU/PCL films showed 93.2% drug release with oxidative stress on THP-1 cells, which causes rupturing and apoptosis of cancerous cells. The Mxene@APU/PCL film can show great potential in future implantable anticancer drug delivery systems.

Synthesis of Zwitterionic Phospholipid-Connected Silane Coupling Agents and Their Hybridization with Graphene Oxide

The hybridization of lipids with graphene is expected to produce a promising, novel biomaterial. However, there are limited examples of the covalent introduction of lipid molecules, especially the immobilization of lipid molecules, onto graphene on a substrate. Therefore, we investigated the hybridization of a silane coupling agent having phospholipid moieties with graphene oxide on substrates prepared by photo-oxidation using chlorine dioxide. Three silane coupling agents with different carbon chain lengths (C4, C6, C8) were synthesized and phospholipid molecules were introduced onto graphene on a substrate. Phospholipid-immobilized graphene on a grid for TEM (transmission electron microscope) was used for EM analysis of proteins (glyceraldehyde 3-phosphate dehydrogenase and β-galactosidase), enabling the observation of sufficient particles compared to the conventional graphene grid.