Graphene has been studied thoroughly for its use in biomedical applications over the last decades. A crucial factor for a material to be used in such applications is its biocompatibility. Various factors affect the biocompatibility and toxicity of graphene structures, including lateral size, number of layers, surface functionalization, and way of production. In this work, we tested that the green production of few-layer bio-graphene (bG) enhances its biocompatibility compared to chemical-graphene (cG). When tested against three different cell lines in terms of MTT assays, both materials proved to be well-tolerated at a wide range of doses. However, high doses of cG induce long-term toxicity and have a tendency for apoptosis. Neither bG nor cG induced ROS generation or cell cycle modifications. Finally, both materials affect the expression of inflammatory proteins such as Nrf2, NF-kB and HO-1 but further research is required for a safe result. In conclusion, although there is little to choose between bG and cG, bG’s sustainable way of production makes it a much more attractive and promising candidate for biomedical applications.

This study endeavored to design and develop an innovative closed-loop diagnostic and therapeutic system with the following objectives: (a) the noninvasive detection of glucose concentration in sweat utilizing nanonengineered screen-printed biosensors; (b) the management of measured data through a specialized computer system comprising both hardware and software components, thereby enabling the precise control of therapeutic responses via a patch-based nanomedicine delivery system. This initiative addresses the significant challenges inherent in the management of diabetes mellitus, including the imperative need for glucose-level monitoring to optimize glycemic control. Leveraging chronoamperometric results as a foundational dataset and the in vivo hypoglycemic activity of nanoemulsion formulations, this research underscores the efficacy and accuracy of glucose concentration estimation, decision-making mechanism responses, and transdermal hypoglycemic treatment effects, within the proposed system.

Diabetes mellitus’ (DM) prevalence worldwide is estimated to be around 10% and is expected to rise over the next decades. Monitoring blood glucose levels aims to determine whether glucose targets are met to minimize the risk for the development of symptoms related to high or low blood sugar and avoid long-term diabetes complications. Continuous glucose monitoring (CGMs) systems emerged almost two decades ago and have revolutionized the way diabetes is managed. Especially in Type 1 DM, the combination of a CGM with an insulin pump (known as a closed-loop system or artificial pancreas) allows an autonomous regulation of patients’ insulin with minimal intervention from the user. However, there is still an unmet need for high accuracy, precision and repeatability of CGMs. Graphene was isolated in 2004 and found immediately fertile ground in various biomedical applications and devices due to its unique combination of properties including its high electrical conductivity. In the last decade, various graphene family nanomaterials have been exploited for the development of enzymatic and non-enzymatic biosensors to determine glucose in biological fluids, such as blood, sweat, and so on. Although great progress has been achieved in the field, several issues need to be addressed for graphene sensors to become a predominant material in the new era of CGMs.

Graphene-based nanomaterials have transformed biomedical applications due to their exceptional physicochemical properties, and nitrogen (N)-doping further enhances the electrocatalytic activity of graphene. Driven by the demand for safer and more sustainable nanomaterials, in this work, we compared eco-friendly produced N- doped graphene (bD) with conventionally synthesized N- doped graphene (cD) in three different cell lines. Across all cell types and assays, cD was more toxic than bD. In NIH/3T3 fibroblast cells, cD activated the Nrf2 signaling pathway, whereas in HaCaT keratinocytes, it triggered oxidative stress responses and increased the apoptotic population. High doses of cD also affected THP-1-derived macrophages by inducing apoptosis and arresting the cell cycle in the G0/G1 phase. Although high doses of bD were also cytotoxic, overall, its effects were milder than cD. Our results confirm that green exfoliation of N- doped graphene retains its desirable biomedical properties while enhancing its biocompatibility, making bD a safer choice for future biomedical applications.

Porous carbon materials from food waste have gained growing interest worldwide for multiple applications due to their natural abundance and the sustainability of the raw materials and the cost-effective synthetic processing. Herein, orange waste-derived porous carbon (OWPC) was developed through a freeze-drying method to prevent the demolition of the original biomass structure and then was pyrolyzed to create a large number of micro, meso and macro pores. The novelty of this work lies in the fact of using the macro-channels of the orange waste in order to create a macroporous network via the freeze-drying method which remains after the pyrolysis steps and creates space for the development of different types of porous in the micro and meso scale in a controlled way. The results showed the successful preparation of a porous carbon material with a high specific surface area of 644 m² g⁻¹ without any physical or chemical activation. The material’s cytocompatibility was also investigated against a fibroblast cell line (NIH/3T3 cells). OWPC triggered a mild intracellular reactive oxygen species production without initiating apoptosis or severely affecting cell proliferation and survival. The combination of their physicochemical characteristics and high cytocompatibility renders them promising materials for further use in biomedical and pharmaceutical applications.

In this study, we investigated the structural, thermal, and cytotoxic properties of Mg-Al layered double hydroxides (LDHs) intercalated with quercetin. Fourier transform infrared (FTIR) and Raman spectroscopy confirmed the successful incorporation of quercetin into the LDH structure, while X-ray diffraction (XRD) showed an increased interlayer spacing due to quercetin intercalation. Thermogravimetric analysis (TGA) demonstrated greater thermal degradation in quercetin-intercalated LDHs compared to nitrate-intercalated LDHs, suggesting a higher quercetin content in the material. Atomic force microscopy (AFM) indicated morphological changes with quercetin, particularly larger surface clusters at room temperature. Cytotoxicity assays revealed that quercetin-intercalated LDHs exhibited a dose- and time-dependent reduction in cell viability, which was more pronounced at higher concentrations and longer exposure times. Quercetin alone had a stronger cytotoxic effect on NIH/3T3 cells compared with Saos-2 cells. Additionally, reactive oxygen species (ROS) assays showed distinct effects of quercetin on both cell lines. These findings highlight the potential of quercetin-LDH hybrids for biomedical applications, particularly for targeted drug delivery.