Tissues on a chip are sophisticated 3D in vitro microphysiological systems designed to replicate human tissue conditions within dynamic physicochemical environments. However, the current fabrication methods for tissue spheroids on a chip require multiple parts and manual processing steps, including the deposition of the spheroids onto prefabricated “chips.” These challenges also lead to limitations regarding scalability and reproducibility. In order to overcome these challenges, we employed 3D printing techniques to automate the fabrication process of tissue spheroids on a chip. This allowed for the simultaneous high-throughput printing of human liver spheroids and their surrounding polymeric flow chamber “chips” containing inner channels in a single step. The fabricated liver tissue spheroids on a chip (LOC) were subsequently subjected to dynamic culturing utilizing a peristaltic pump, enabling assessment of cell viability and metabolic activities. The 3D printed liver spheroids within the printed chips demonstrated high cell viability (>80%), increased spheroids size, and consistent ATP activity and albumin production for up to 14 days. Furthermore, we conducted a study on the effects of acetaminophen (APAP), a nonsteroidal anti-inflammatory drug, on the LOC. Comparative analysis revealed a substantial decline in cell viability (<40%), diminished ATP activity, and reduced spheroid size after 7 days of culture within the APAP-treated LOC group, compared to the non-treated groups. These results underscore the potential of 3D bioprinted tissue chips as an advanced in vitro model that holds promise for accurately studying in vivo biological processes, including the assessment of tissue response to administered drugs, in a high-throughput manner.

Here we described an aptasensor based on graphene oxide (GO) decorated with gold nanoparticles (AuNPs) able to detect the AR released by prostate cells, in order to provide new insights about the relationship between AR and prostate cancer for a more precise diagnosis for cancer. Characterization of the surface modified GE was carried out by cyclic voltammetry and electrochemical impedance spectroscopy using ferrocene as a redox probe. Under the optimized experimental conditions, a detection limit of 0.5 ng/mL (3σ/slope) was obtained by the present electrochemical biosensor, along with a linear range of 0-110 ng/mL. By virtue of excellent sensitivity, specificity, and repeatability, the present electrochemical biosensor provides a potential application in clinical diagnosis.

The increasing prevalence of pathogen outbreaks underscores the urgent need for rapid, accurate, and cost-effective diagnostic tools. Colorimetric detection has gained significant attention among the available techniques due to its simplicity, portability, and potential for point-of-care applications. The nanomaterial-based colorimetric detection field continues to evolve, with innovations focusing on improving sensitivity, specificity, robustness, cost-effectiveness, and friendly analysis. Additionally, efforts to address limitations, such as stability and environmental impact, pave the way for more sustainable and reliable diagnostic solutions. This review highlights recent advances in nanomaterials for colorimetric pathogen detection in the last five years.

Direct detection of dopamine (DA) in serum samples without any type of extraction or pre-treatment has been a great challenge for biomedical analysis. This paper reports the development of a sensor consisting of polymer brushes reinforced with multi-walled carbon nanotubes, that was used to determine levels of dopamine in human blood serum. The structure and morphology of the as-prepared hybrid nanomaterials were characterized and confirmed by scanning electron microscopy and electrochemistry techniques. This methodology employs differential pulse voltammetry to detect dopamine in human serum samples at concentrations ranging from 0.1 μM to 10 μM with an obtained detection limit of 40.5 nmol L⁻¹ (R = 0.996). This sensor provides an inexpensive and easy-to-use device with high degrees of sensitivity and selectivity for monitoring DA in human blood serum samples.