Biosensors & Biosensing Technology

Abstract: Scalable Breath Figure–Engineered Periodic Silver Nanostructures on Polymeric
Substrates for Ultrasensitive and Reusable SERS Biosensing

Surface-Enhanced Raman Scattering (SERS) has emerged as a promising next
generation biosensing technology due to its molecular specificity and ultrahigh sensitivity.
However, the practical translation of SERS into real-world biosensing platforms remains
constrained by expensive fabrication routes, limited scalability, and poor reusability of
conventional substrates. In this work, we report a scalable, low-cost, and reusable photonic
plasmonic biosensing platform fabricated via the breath figure (BF) self-assembly approach,
addressing key challenges in the development of future biosensors.
The BF method enables the formation of large-area, highly ordered periodic polymeric
architectures that act as templates for the controlled confinement of silver nanostructures,
thereby generating dense electromagnetic hotspots essential for ultrasensitive detection. Both
in-situ chemical reduction and ex-situ plasma-assisted infiltration strategies were employed to
precisely engineer nanoparticle distribution and interfacial coupling, achieving femtomolar
level detection limits (down to 0.1 fM) for model analytes. The resulting platforms exhibit
excellent spectral resolution, high analytical enhancement factors (~107), and outstanding
batch-to-batch reproducibility (RSD ~4.2%), fulfilling critical requirements for next
generation sensing technologies.
Importantly, TiO2-assisted photocatalytic regeneration enables efficient analyte removal and
signal recovery exceeding 93% over multiple reuse cycles, highlighting the platform’s
sustainability and long-term operational stability. Interfacial charge-transfer mechanisms
revealed through XPS analysis further underline the intelligent material design contributing to
sensor regeneration. Successful detection in complex real samples demonstrates the platform’s
applicability beyond laboratory conditions.
Overall, this work presents a future-ready SERS biosensing architecture that integrates
scalability, reusability, and ultrasensitivity within a single material system. The approach offers
a viable pathway toward next-generation, field-deployable biosensors for environmental
monitoring, biomedical diagnostics, and point-of-care analytical technologies.

Abstract: Advances in Point-of-Care Technologies for Biomedical Applications

 The incorporation of functionalized and modified micro- and nanostructures into biomedical applications has sparked significant research interest in recent years. Micro- and nanotechnology's potential in medicine and biomedical engineering is vast, encompassing areas such as implant and tissue engineering, as well as diagnosis and therapy. The current landscape demands the design of micro- and nanodevices that can effectively address biological challenges, leading to more efficient biomedical solutions. This presentation will focus on recent advancements in point-of-care (POC) systems developed within various European projects for handling and quantitative analysis. Specifically, the Hearten and KardiaTool projects aim to diagnose and monitor heart failure in patients by analyzing breath and saliva samples, enhancing analysis speed and efficiency while reducing sample and reagent consumption. These devices are capable of performing tasks such as sample pretreatment, separation, dilution, mixing, chemical reactions, detection, and product extraction. The entire analysis process can be fully automated, minimizing human involvement, preventing contamination, and ensuring repeatable experiments. Additionally, this presentation will address the challenges of scaling up POC devices, covering: (i) the fabrication of sensors and microfluidic devices, (ii) sensor functionalization to improve performance and capabilities, (iii) integration of existing detection techniques into the POC platform, and (iv) the development of quantitative readout extraction via handheld devices.

Abstract:
Climate-smart agriculture (CSA) emphasizes sustainable practices that enhance productivity, resilience, and environmental stewardship in the face of climate change. A critical enabler of CSA is the integration of advanced sensing technologies, particularly biosensors, which provide real-time, precise, and cost-effective monitoring of agricultural systems. Biosensors—analytical devices that couple biological recognition elements with transducers—offer unique advantages in detecting soil nutrients, water quality, plant health, and greenhouse gas emissions. Their application in agriculture enables farmers to optimize resource use, reduce input waste, and mitigate environmental impacts. For instance, soil nutrient biosensors can guide site-specific fertilizer application, while plant stress biosensors detect early physiological changes caused by drought, salinity, or pathogen attack, allowing timely interventions. Additionally, biosensors for methane and nitrous oxide monitoring contribute to quantifying and reducing agricultural emissions, aligning with global climate goals. Recent advances in nanotechnology, microfluidics, and wireless communication have further enhanced biosensor sensitivity, portability, and integration into digital farming platforms. When combined with data analytics and IoT-based decision support systems, biosensors create a feedback loop that empowers farmers with actionable insights, fostering resilience against climate variability. Despite challenges such as scalability, cost, and durability under field conditions, biosensors represent a transformative tool for achieving sustainable intensification and climate-smart outcomes. In conclusion, the biosensors play a pivotal role in bridging biological processes with precision agriculture, underscoring their potential to revolutionize monitoring, management, and sustainability in modern farming systems.

Abstract: A New Paradigm for Assessing Strain Reliability in Flexible Organic Electronics

Flexible and wearable electronics demand transistor technologies that can sustain stable performance under extreme mechanical deformation. In this work, propose a quantitative benchmarking framework for strain resilience in organic thin-film transistors (OTFTs), introducing three normalized metrics: the Degradation Factor (DF), quantifying drain-current loss under strain; the Mobility Factor (MF), representing the rate of charge-transport degradation per unit strain; and the Strain-Stability Window (SSW), defining the maximum strain range within which devices remain in the safe operating zone (DF < 15%) . Using Silvaco Victory TCAD, systematically investigate the strain-dependent behaviour of single-dielectric (Al₂O₃) and hybrid-dielectric (Al₂O₃/PVP) OTFTs under both compressive (concave) and tensile (convex) bending with radii from 8 µm to 1 µm. Results show that hybrid dielectric OTFTs exhibit superior strain tolerance, with a degradation factor of only 9% under 9.85% tensile strain, compared to 25% for single-dielectric devices. Furthermore, hybrid devices show a markedly lower mobility factor ( -3 %/strain compressive, -1.9 %/strain tensile) compared with single-dielectric OTFTs (-6 %/strain compressive, -5 %/strain tensile). Beyond confirming the mechanical advantages of hybrid dielectrics, This work study demonstrates that strain-stability quantifiers provide a universal method to benchmark flexible OTFT reliability, bridging device physics with practical requirements of wearable bioelectronics. These findings establish hybrid Al₂O₃/PVP dielectrics not only as performance enhancers but also as reliable design enablers for next-generation strain-resilient organic electronics.