The precise monitoring of environmental contaminants and agricultural plant stress factors, respectively responsible for damages to our ecosystems and crop losses, has nowadays become a topic of uttermost importance. This is also highlighted by the recent introduction of the so-called “Sustainable Development Goals” of the United Nations, which aim at reducing pollutants while implementing more sustainable food production practices, leading to a reduced impact on all ecosystems. In this context, the standard methods currently used in these fields represent a sub-optimal solution, being expensive, laboratory-based techniques, and typically requiring trained personnel with high expertise. Recent advances in both biotechnology and material science have led to the emergence of new sensing (and biosensing) technologies, enabling low-cost, precise, and real-time detection. An especially interesting category of biosensors is represented by field-effect transistor-based biosensors (bio-FETs), which enable the possibility of performing in situ, continuous, selective, and sensitive measurements of a wide palette of different parameters of interest. Furthermore, bio-FETs offer the possibility of being fabricated using innovative and sustainable materials, employing various device configurations, each customized for a specific application. In the specific field of environmental and agricultural monitoring, the exploitation of these devices is particularly attractive as it paves the way to early detection and intervention strategies useful to limit, or even completely avoid negative outcomes (such as diseases to animals or ecosystems losses). This review focuses exactly on bio-FETs for environmental and agricultural monitoring, highlighting the recent and most relevant studies. First, bio-FET technology is introduced, followed by a detailed description of the the most commonly employed configurations, the available device fabrication techniques, as well as the specific materials and recognition elements. Then, examples of studies employing bio-FETs for environmental and agricultural monitoring are presented, highlighting in detail advantages and disadvantages of available examples. Finally, in the discussion, the major challenges to be overcome (e.g., short device lifetime, small sensitivity and selectivity in complex media) are critically presented. Despite the current limitations and challenges, this review clearly shows that bio-FETs are extremely promising for new and disruptive innovations in these areas and others.

CNTs based chemiresistive gas sensors are known to not fully recover to the baseline after gas exposure. This is why often heat is applied to thermally activate the sensor and improve the gas desorption process occur- ring at the surface. In this paper, we combine single-walled CNTs (SWCNTs) with conjugated polymers (CPs) i.e., Poly(3-hexylthiophene)(P3HT), to realize chemiresistive gas sensors with improved recovery. Five configurations were fabricated with diverse positions of the sensing material layers with respect to the interdigitated electrodes (IDEs), namely: SWCNTs/IDEs and P3HT/IDEs as controls for the CNTs and P3HT singular materials; SWCNTs/P3HT/IDEs, SWCNTs/IDEs/P3HT and P3HT/SWCNTs/IDEs as combined sensing materials layers configurations. The results show that in particular, the P3HT/SWCNTs/IDEs sensors exhibit better performance with respect to the other configurations when exposed to 5, 25, and 50 ppm NH3. Improvements in terms of response time (103 seconds faster at 5 ppm), sensor response (+26.83% at 50 ppm), and improved recovery to the baseline (+25.69% and +11.34% at 5 and 50 ppm respectively) were obtained when evaluated against SWCNTs/IDEs sensors. These findings suggest that addition of CPs (i.e. P3HT) may be a promising approach to enhance the performance and stability of SWCNTs-based chemiresistive gas sensors, providing a new direction for future research in this field. Future research to investigate the effect of others CPs on the CNTs based chemiresistive gas sensors will be needed to realize more efficient and reliable ammonia gas sensors.

Light control of living systems is an emerging field in bioelectronics, in regenerative medicine and cell‐based therapy. Herein, the design of a semitransparent bio–photoelectrolytic platform for control of a neuroblastoma cell line via light pulses is laid out. The platform is based on conjugated polymer films interfaced with a biological electrolyte solution confined in a compact chamber. Human SH‐SY5Y neuroblastoma cells are cultured for 3 days on the organic semiconductor and subjected to a pulsed light protocol. At the end of the culture time, proliferative activity of cells on the polymer film subjected to light pulses is reduced by 50% compared to the cultures kept in dark. An increase in intracellular Ca²⁺ level is observed, indicating a significant perturbation of the equilibrium potential of the cells. It is shown that the platform, in a sandwich‐type closed architecture with two transparent electrodes, can provide a tool for the initial recording of bioelectrical photovoltage signals (mV) that can complement analysis with more sophisticated electrophysiological tools. Obtained results can pave the way to new noninvasive photomanipulation techniques to stimulate/control living cells and their proliferation through both optical and electrical stimulation and probes, for application in the fields of biosensing and biomedicine.

The field of biotechnology has rapidly grown in recent years leading to unprecedent achievements in regenerative medicine and tissue engineering. Among latest high-tech available technologies, 3D bioprinting can be surely considered the most promising to develop complex structures mimicking organs and tissues, as well as functional 3D cell scaffolds. If supplemented with organic functional materials, engineered cell scaffolds can be used as bioelectronic interfaces and biomedical sensors. In this work, a novel 3D-bioprinted cell scaffold enhanced with light-responsive organic semiconducting polymer nanoparticles (100-nm hydrodynamic diameter, absorbance spectra peak at λ = 496 nm, and emission spectra peak at λ = 645 nm) is presented. The light-sensitive cell scaffold offers excellent biocompatibility and support of cell growth. The 3D-bioprinted biocompatible light-sensitive cell scaffolds can be used for light control and modulation of cellular activities in a 3D and real-mimetic tissue/organ-like environment, paving the way to new applications in neural engineering and regenerative medicine.

Conducting polymers (CPs) are highly susceptible to ammonia ( NH 3 ) at room temperature. This has spurred growing interest in CP-based NH 3 gas sensors across diverse fields, ranging from biomedicine to environmental monitoring. Detecting NH 3 levels in breath, from parts per million to parts per billion, aids in diagnosing health conditions like liver and kidney dysfunction. Despite the importance of CP-based NH 3 sensors, a comprehensive assessment of their performance, limitations, and prospects has yet to be conducted. To address this gap, this work provides a detailed review of chemiresistive NH 3 sensors based on CPs (including P3HT, PEDOT, PPy, and PANI), examining sensor response, selectivity, stability, repeatability, and sensitivity to environmental factors like humidity and temperature. The role of porous structures and gas diffusion mechanisms in enhancing CP sensor performance is emphasized, alongside CP-based composite materials. The mechanical flexibility of these sensors is analyzed and compared, highlighting their potential for integration into flexible and wearable devices. Key challenges for CP-based NH 3 sensors include poor selectivity due to interference from similar gases, sensitivity loss caused by humidity-induced CP swelling, and instability from temperature fluctuations. Additionally, the lack of standardized testing protocols complicates performance comparisons of CP-based NH 3 sensors. Future research should focus on improving CP porosity, understanding gas-CP interactions, developing stable composites, and exploring new CPs for improved NH 3 sensing.