Canaries thrive in the air and fish in water, providing rapid and sensitive readings of their environments. Humans can detect volatile organic compounds and toxic chemicals but cannot accurately estimate exposure levels, especially when using protective gear. In space, bacterial bioreporters can measure cumulative radiation exposure, whereas, on Earth, they can estimate air exposure levels. Bioluminescent biosensors have emerged as promising tools for air toxicity assessment, offering sensitive and low-cost air quality monitoring. Despite working in real time, these bioreporters need nearly an hour to respond, which is negligible for long exposures. Thus, genetically engineered bacteria can be used in wearable sensor systems. We will describe how our whole-cell biosensors can be used to monitor exposure to harmful substances in real time in environmental or occupational air, providing an estimation of toxicity, which no enzymatic sensor can provide, due to not being ‘living.’ The lux reporter system generates luminescence, which can be converted to an electrical signal if needed. Our wearable design involves an array of five bioreporters immobilized onto alginate hydrogels integrated into clothing. Readings are taken offline to prevent light contamination, and the accumulated data provide insight into exposure and health risks. Industrial workers, urban dwellers in polluted cities, and first responders would benefit from these patches, which only require connection to an offline reading device for immediate results. Bacterial bioreporters are immobilized in calcium alginate pads that maintain humidity and allow gas diffusion. The bacteria respond semi-quantitatively to toxic aerosols, providing a response within one hour of exposure.

Introduction

Human activities beyond Earth have steadily increased. During spaceflight, NASA observed that the lack of Earth's gravity causes a 1-1.5% monthly loss in the mineral density of weight-bearing bones. Even after returning, rehabilitation may be ineffective. The effects extend to muscles, the neuro-vestibular system, heart, eyes, and more. Understanding microgravity's effects on the human body is critical; however, sending samples to space is costly and time-consuming. Thus, technologies like the clinostat can simulate microgravity on Earth.

Methods

RBCs from cancer patients are used to investigate the impacts of microgravity. The link between microgravity-induced metabolic changes in their morphology and cytoplasm properties is poorly understood. To explore these changes, we will expose the RBCs to microgravity using a 3D clinostat, and using dielectrophoresis, an electrokinetic technique, we will analyze the dielectric profile related to morphological and cytoplasmic changes. The cells are suspended in media (8.6wt% sucrose + 0.3wt% dextrose in 100ml DI water), transferred into 1.5-ml centrifuge tubes, and exposed to microgravity for 1-24 hours at a specific conductivity (0.01 S/m), adjusted with 1xPBS.

Results

Cell behavior is quantified using the DEP crossover technique (when no DEP force occurs), where cells neither migrate toward nor away from the high electric field region at a specific AC frequency and peak-to-peak voltage. The results show statistically significant variations in membrane permittivity and conductivity between Earth and microgravity conditions. The folding factor of microgravity-induced cells decreased drastically. A decrease in the folding factor suggests altered cell structure and function, potentially affecting protein folding, morphology, and cellular processes.

Conclusions

These results help understand the effect of microgravity on changes in the morphology and cytoplasm of RBCs. The goal of this research is to enhance the understanding of the impacts of microgravity on the human body and advance space health studies.

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer, and is known to have an extremely low survival rate. The lack of early diagnostic techniques and tools, combined with non-specific symptoms, makes PDAC undetectable until it reaches advanced stages. PDAC is known to have resistance to treatment, largely due to the tumor's ability to suppress natural killer cells. Given the high mortality rate associated with this aggressive PDAC, there is an urgent need for innovative diagnostics to enable early detection, followed by an adequate and effective treatment procedure.

In this study, we used dielectrophoresis (DEP) to obtain dielectric profiles of peripheral blood mononuclear cells (PBMCs) isolated from PDAC patients under a non-uniform electric field gradient. Our hypothesis is based on cellular changes caused by PDAC interacting with the immune system, subsequently affecting the extracellular matrix (ECM) of the plasma membrane and the cell interior of PBMCs. These changes, resulting from the aggressive growth of dense fibrotic stroma, influence the cells' size, shape, permittivity, conductivity, and other dielectric properties, potentially serving as reliable biomarkers for early PDAC detection.

Using a single-shell model in 3DEP, we quantified the electrophysiological properties to discriminate PDAC PBMCs from non-cancerous pancreatic PBMCs in benign or pre-cancerous states by comparing their electrical biomarkers. Our preliminary results show significant differences in cytoplasm conductivity, membrane permittivity, conductance, and capacitance parameters of the PBMCs. These findings highlight the potential of dielectrophoresis as a technique for developing a diagnostic device for PDAC, providing relevant insight into cellular changes associated with the disease while enhancing our clinical understanding of its pathophysiology. This study has great potential for the development of accessible point-of-care devices for early PDAC diagnosis.

Introduction

Harmful algal blooms (HABs) happen when colonies of algae grow out of control and exert toxic or harmful effects on people and marine life. Human diseases caused by HABs can be severe and, in some cases, fatal. Chlorella vulgaris is a type of green microalgae that can be found in freshwater. Chlorella is a dominant species in HABs. Various methods are available for detecting HABs, including light microscopy, flow imaging microscopy, immunoassays, and liquid chromatography. However, these techniques have several limitations, such as high costs, lengthy analysis times, the need for specialized training, and the inability to perform on-site detection. To address these challenges, we propose a novel detection approach utilizing the dielectrophoresis (DEP) technique. A critical step in developing this detection tool is characterizing the dielectric profile of Chlorella vulgaris.

Methods

Chlorella vulgaris was cultivated in Proteose medium under a 16:8-hour light cycle, positioned 18 inches from the light source. After cultivation, the cells were resuspended in a buffer solution containing 8.5 g of sucrose and 0.3 g of glucose, with conductivities adjusted to 100, 200, 300, 400, and 500 μS/cm. Using 3DEP equipment, we characterized the dielectric properties of Chlorella vulgaris, including cytoplasm conductivity, cytoplasm permittivity, specific membrane conductance, and specific membrane capacitance.

Result

Data collection and analysis are ongoing, and the complete results will be presented at the conference.

Conclusion

Data collection and analysis are ongoing, and complete conclusions will be presented at the conference.

CRISPR-Cas systems serve as an adaptive immune mechanism in prokaryotes, targeting and neutralizing mobile genetic elements. These systems are categorized into two main classes and various subtypes, with Type III systems being particularly distinctive for their RNA-targeting capabilities. Using a multi-subunit effector complex guided by CRISPR RNA (crRNA), these systems recognize and degrade foreign RNA molecules. This process also activates the Cas10 subunit, initiating the production of cyclic oligoadenylate (cOA) signaling molecules. These cOA molecules then activate effector proteins equipped with sensory domains, which drive further biochemical reactions.

Type III CRISPR-Cas systems have been repurposed for innovative nucleic acid detection due to their ability to amplify signals. One established approach uses Csx1, an RNase activated by cOA, in conjunction with an RNA-targeting complex, to produce a detectable fluorescent signal. However, fluorescence-based methods rely on external light sources, complicating their use in portable diagnostic devices.

To address this limitation, a chemiluminescent (CL) detection strategy was developed. This technique employs a G-quadruplex (G4) RNA probe, which catalyzes a chemiluminescent reaction between luminol and hydrogen peroxide in the presence of hemin. When the target RNA is present, Csx1 is activated by the CRISPR-Cas complex, leading to the degradation of the G4 probe and resulting in the loss of the chemiluminescent signal. This method offers a simple, highly sensitive detection system without the need for external light sources. The chemiluminescent readout provides a practical solution for creating portable and efficient diagnostic tools, making it an ideal choice for on-site nucleic acid testing.

This work was supported by the Nano-ImmunoEra project that has received funding from the European Union’s MSCA Staff exchange Horizon Europe programme, Grant Agreement Number 101086341.

Introduction:
Acetylcholine (AChE) is an essential enzyme in neurotransmission, and its inhibition serves as a diagnostic marker for diseases like Alzheimer's and poisoning by organophosphates. We investigate an AChE-based electrochemical biosensor with an integrated microfluidic platform for the sensitive and rapid detection of AChE inhibitors. The biosensor utilizes a working electrode designed using MEMS (Micro-Electro-Mechanical Systems) technology, incorporating a Glassy Carbon Electrode (GCE), Gold Nanoparticles (AuNPs), PEDOT:PSS, and Carbon Nanotubes (CNTs), intended to detect pico-molar concentrations.

Methods:
The AChE enzyme was immobilized onto the electrode surface of a microfluidic chip, facilitating precise control of the sample, and the reagent flow was studied in an FEM-based numerical platform. The MEMS-based working electrode was designed, and subsequently, an optimized structure was fabricated. The said electrode featuring a GCE modified with AuNPs, PEDOT:PSS, and CNTs was designed to maximize the electron transfer and enhance the conductivity. This design enabled the sensor to detect AChE inhibitors with high sensitivity. Amperometric and cyclic voltametric techniques were employed to evaluate the sensor’s performance, including its detection limit, response time, and selectivity for common AChE inhibitors such as organophosphates. The mathematical modeling of the sensor included a mass transport equation for the electrode and the active molecules in the DLME, the electron transfer reaction on the working electrode, and the charge transfer kinetics. The model was validated and rigorously investigated through the depletion of concentrations of PBS and blood, where the applied potential affected the current through the electrolytes. The CV of the sensor was plotted for peak potential (0.4 v) and peak current (8 pA to 100 nA) measurements with respect to the concentration. Further, an EIS study was carried out, and the CV response was studied using different scan rates and redox couple concentrations. The observed peaks indicated the detection of biomolecules even at pico-molar concentrations.

Results:
The presented MEMS-based microfluidic integrated electrochemical biosensor demonstrated excellent pico-molar sensitivity, with detection limits as low as the 10 picomolar level for acetylcholine and its inhibitors. The inclusion of AuNPs and CNTs significantly enhanced the electrochemical response, while PEDOT:PSS improved the electrode's stability and conductivity. The microfluidic platform ensured rapid (< 10 seconds) and selective detection, with the sensor maintaining high sensitivity over several weeks of use.

Conclusions:
The presented AChE biosensor, designed using MEMS technology and an advanced electrode with multilayered materials, offers a highly sensitive, rapid, and cost-effective approach to detecting AChE inhibitors, even at pico-molar concentrations, in a robust device configuration. The integration of microfluidic control and MEMS technology enhances the system’s potential for applications in environmental monitoring, clinical diagnostics, and toxicological testing. Future improvements could focus on further optimizing the sensor for portability and enhancing its selectivity in complex biological matrices.

Fulvic acid (FA) is a water-soluble molecule belonging to the group of organic compounds called humic substances, which are derived from the decomposition of organic matter. Known for its significance in soil fertility and nutrient availability, it is considered a water pollutant due to its ability to become precursor for the formation of toxic halogenated disinfection by-products and complexes with heavy metals in soil. Several methods have been developed to remove this in water, such as coagulation and adsorption methods, but the efficiency is significantly affected by different factors such as the solubility, size, and concentration of the molecule.

Molecularly imprinted polymers (MIPs) are synthetic polymers that show promising properties to become an adsorbent for the removal of FA in water. MIPs exhibit robustness even in high pH and high temperature conditions and high selectivity for the target even in the presence of matrix interferers; they are also reusable, and their synthesis is simple and straightforward. This study explored the formulation of MIPs specific for FA using methacrylic acid, methacrylamide, and acrylamide as functional monomers.

Prior to MIP synthesis, this study employed the functionalization of silica gel with chitosan, followed by the immobilization of FA as the target and humic acid (HA) as the control molecule on the functionalized silica gel. Verification was performed through a series of FT-IR analyses conducted to ensure accuracy and consistency in the processes. The MIP’s selectivity was tested using HA, the control molecule. After the three-hour contact time with triplicate samples of FA and HA separately, the initial and final concentrations of MIP were analyzed using UV-Vis spectroscopy at a 190-400 nm range.

The 30 ppm MIP solution exhibited 65% FA recovery versus 1.69% HA recovery, proving the selectivity of the synthesized MIP towards the target. This paper could lay the groundwork for future researchers aiming to advance the development of a similar sensor or other innovations.

Carbendazim (CBZ) is a fungicide that is widely used in agriculture for controlling fungal diseases. However, its excessive presence in food, feed, agricultural soils, and water bodies poses severe environmental, human, and animal health risks due to its toxicity. Among the various available detection techniques, aptamers have gained prominence as highly sensitive, cost-effective, and reliable tools for on-site detection. This study employed gold nanoparticles (GNPs) combined with the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method, specifically using the GOLD-SELEX approach, to identify a highly specific and sensitive aptamer for CBZ detection in food and feed products. The process involved ten rounds of SELEX, incorporating counter-SELEX against commonly used and structurally related pesticides, such as Mancozeb, Chlorpyrifos, Glyphosate, Monocrotophos, Atrazine, Thiamethoxam, and Methyl Parathion, to enhance specificity. A graphene oxide (GO)-based fluorescence assay was utilized to monitor aptamer enrichment throughout the SELEX process. In the final SELEX round, PCR amplification was performed using unmodified primers, and the amplified sequences were cloned using a blunt-end cloning kit from Takara. High-throughput sequencing (HT-SELEX) was then conducted to analyze the abundance and motifs of the enriched aptamers. The identified aptamer sequences will undergo further characterization to determine their dissociation constant (kD) and assess their sensitivity and specificity toward CBZ. Ultimately, the most effective aptamer will be utilized to develop a rapid, cost-effective, and user-friendly diagnostic kit for detecting carbendazim in food and environmental samples.

Mechanical biosensors represent a cutting-edge analytical technology for detecting and measuring biological molecules with unparalleled precision and sensitivity. These innovative devices rely on the integration of biological recognition elements and mechanical transducers to convert molecular interactions into quantifiable signals. Their utility spans a range of applications, including healthcare, environmental monitoring, and food safety, making them indispensable in modern analytical sciences. At the heart of mechanical biosensors are bio-receptors, biological components such as enzymes, antibodies, or nucleic acids, which bind selectively to target molecules. These bioreceptors are immobilized on transducer surfaces using techniques like physical adsorption, covalent bonding, or entrapment, ensuring stable and specific interactions even in complex biological matrices. Advancements in sensor design and material sciences have significantly enhanced the performance of mechanical biosensors. Embedding magnetic elements such as Fe3O4 nanoparticles amplifies detection sensitivity. Mechanical biosensors detect target molecules through surface stress measurement, mass detection, and force sensing. These capabilities make them highly versatile, with applications in medical diagnostics for detecting disease biomarkers, environmental monitoring for identifying pollutants, and food safety for detecting contaminants such as pathogens and chemical residues. Despite their advancements, challenges remain, including minimizing non-specific interactions and improving sensor reproducibility. Future innovations are expected to integrate nanotechnology, multi-analyte detection capabilities, and compact designs for wearable and portable applications.

An electronic stethoscope is designed and implemented for the diagnosis of some cardiac ailments. Graphs of the diagnosis are plotted using the electronic stethoscope, as well as results obtained for the purposes of inferences and analysis. With these inferences, the diagnosis of chest sounds can be easily carried out. With the results of this graph, early diagnoses can be realized, which can hinder cardiological ill health. With the electronic stethoscope, the auscultation of the chest becomes an effective and basic method for the diagnosis of some cardiological problems. An example of these cardiac issues is heart valve malfunction, which leads to heart murmurs. The electronic stethoscope can diagnose grade one and two heart murmurs and auscultation tachycardia patients, which leads to the detection of all kinds of chest sounds that the manual or conventional stethoscope may not be able to detect. In this work, the electret microphone capsule is connected to the microphone amplifier module (LM 386). The LM 386 has built-in automatic gain control (AGC), which is suitable for capturing a wide range of sound levels. The experimental analysis was conducted using multiple subjects to evaluate the system's accuracy, consistency, and noise-filtering capabilities. The device was tested on four subjects. The results are summarized as follows: a normal heart rate of 72 beats and normal heart sounds with a high signal clarity for subject one, and a heart rate of 85 and high noise interference with low signal clarity for subject four. Ten subjects were tested for the Phonocardiogram (PCG), which includes S1, S2, and murmurs. The parameters visualized in the system and plotted in the graph are time ((0.2s, 15db) and (0.5s, -12db)) (in seconds), amplitude (15db, high; -12db, low) (sound intensity in decibels), frequency ((125Hz, 15db) and (100, -12db)) (in hertz), and heart rate variability (HRV) ((68, 0.5s) and (80, 0.5s)).