Advanced Sensor Research最新文献

Urinary tract infections (UTIs) are the most common nosocomial infection in North America leading to over $12 billion in annual health care costs. UTIs can significantly reduce the quality of life and, in severe cases, result in sepsis and mortality. According to Public Health Ontario, over 80% of long-term care home (LTCH) residents with asymptomatic bacteriuria are treated with antibiotics, however, less than 50% of the antibiotic treatments for UTIs show clinical benefit. Current confirmatory processes for UTIs are primarily dependent on the completion of urine cultures which can result in a delay of more than 24 h. Therefore, there is a need to develop new efficient diagnostic methods to provide timely test results and prevent multidrug resistance. Emerging nanomaterials with special physical and chemical properties have demonstrated great potential in rapid detection of UTI-associated bacteria. This review paper provides a thorough analysis of current diagnostic tools for UTIs. Emerging nanostructured biosensors are reviewed to elucidate the most recent progress in the detection of uropathogens. It is believed that advanced biosensors integrated with nanotechnology will contribute to the timely diagnosis of UTIs and improve the accuracy of the results, which will lead to better treatment of this prevalent clinical condition.

Gas sensors based on micro-electromechanical systems (MEMS) offer advantages such as a broad spectrum of potentially sensitive materials and analytes, easy miniaturization and integration, high sensitivity, and low costs. This paper introduces a novel MEMS sensor platform utilizing a suspended gate field effect transistor (SGFET) transducer. In this approach, the flexible gate membrane of the SGFET is coated with a sensitive material exhibiting responsive swelling behavior. For the proof of concept, kraft lignin hydrogel is chosen as a biorenewable material for humidity sensing. A precision dispensing technique is used to deposit kraft lignin hydrogel on the SGFETs. The sensor measurements yield reversible shifts in the sensor's output current of up to 9% in response to 5000 ppm water vapor. The results successfully demonstrate the feasibility of this new sensing platform.

Interactive Wood

Sensors fabricated directly onto wooden surfaces allow to detect humidity and temperature changes or monitor the curing of varnishes. They enable structural integrity monitoring in construction or turn furniture into interactive touch panels, all in a sustainable fashion. More details can be found in article number 2400010 by Martin Kaltenbrunner and co-workers.

The age of antibiotics, which began with the discovery of penicillin in 1929, marks an important period in medical history, as deadly bacterial infections seemed to be a thing of the past. However, the tide turned as more and more resistance to all existing antibiotics emerged, leading to the still ongoing era of antibiotic resistance. To counter this development and slow it down, it is important to administer the appropriate, effective antibiotics, which requires the clinical transition from empirical to targeted antibiotic therapy. Antimicrobial susceptibility testing (AST) is a key pillar in the implementation of targeted antibiotic therapy. This review provides an overview of the different phenotypic and genotypic AST methods with their advantages and disadvantages, focusing on the turnaround time from patient to result, including preculture. In addition, an outlook on their future potential is given, also considering the impact of artificial intelligence on this field.

Continuous Glucose Monitoring (CGM) systems are revolutionizing the real-time tracking of blood glucose levels, a cornerstone in effective diabetes management and optimal glycemic control. Transitioning from the “intermittent readings” offered by traditional Blood Glucose Monitoring (BGM) methods, CGM delivers an “uninterrupted flow” of glucose data, enabling a “more detailed” strategy for meeting treatment goals. Initially, the “uptake of CGM faced hurdles due to doubts about its precision, but continuous advancements in technology have not only resolved these concerns but also confirms CGM as a dependable and impactful instrument in diabetes management”. Concurrently, advancements in insulin pump technology have improved their portability and ease of use, greatly increasing patient adoption. The market reflects a growing demand for such innovative healthcare solutions, driven by an increased awareness of diabetes management and bolstered by supportive healthcare policies. Future prospects for CGM and insulin pump technologies are incredibly promising, offering the potential for highly personalized care and sophisticated treatment strategies. This paper aims to explore how the synergy between ongoing technological developments and evolving market dynamics is set to redefine the diabetes care paradigm, positioning CGM and insulin pumps as essential elements in enhancing the quality of life for individuals with diabetes.

Chronic kidney disease (CKD) is a significant global health concern, impacting over 10% of the world population. Despite advances in home-based treatments, CKD diagnosis and monitoring remain centralized in large laboratories. This work reports on the development of a Graphene-based Lab-On-a-Chip (G-LOC) for the self-testing of multiple renal function biomarkers in capillary blood. G-LOC integrates bioelectronic sensors with a 3D-printed microfluidic system that enables the multiplex quantification of urea, potassium, sodium, and chloride, from one drop of blood. The potentials of three graphene sensors modified with ion-selective membranes and enzymes are simultaneously measured. The analytical performance of the test is evaluated in terms of linearity, accuracy, and coefficient of variability (CV). Accuracy values higher than 98.7%, and CV values lower than 10.8% are obtained for all the biomarkers. Correlation and Bland–Altman plots show good correlation (slopes in the range of 0.94–1.15) and high agreement of G-LOC with a reference method. It is also demonstrated that the test can correctly differentiate biomarker levels normally obtained for healthy people, early-stage CKD, and end-stage CKD. Finally, user experience is studied with a group of untrained volunteers who highlight the simple usability of the test and its suitability for at-home diagnostics.

The use of hydrogen as an energy carrier will require low-cost, low-power hydrogen sensors. Toward this goal, penta-twinned palladium nanowires (Pd NWs) are synthesized and fabricated sensors from them by drop-casting. Pd NWs drop-cast onto an interdigitated electrode (IDE) gave a response of 0.3% to 1 vol.% H₂, with response and recovery times of 12 and 20 s, respectively. However, they exhibited a negative response (decreased resistance) at low H₂ concentrations. Pd NWs on a paper substrate provided a tenfold higher response to 1 vol.% H₂, with response and recovery times of 10 s each, but still exhibited negative response at low H₂ concentration. Exposing the Pd NW-on-paper sensor to ozone-generating UV light degraded the PVP used in Pd NW synthesis, eliminating the reverse sensing response, and providing a response of 5% to 1 vol.% H₂, with response and recovery times of 15 s. This allowed reliable H₂ detection down to 100 ppm H₂. Finally, coating the Pd NWs with a small amount of Pt (<5%) reduced the response and recovery times to 5 s by catalyzing H₂ dissociation. This work provides a path to low-cost sensors to enable the safe use of H₂ as an energy carrier.

Measurements of low-frequency physiological signals, such as heart rate and pulse waves, play an essential role in biomedical applications for the early diagnosis of abnormal cardiovascular activities. Recent advances in flexible mechanical electronics represent a novel concept of miniaturized, wearable sensors for heart rate measurement that can be used in ambulatory environments. However, most mechanical sensors require the sensing element to be placed directly on the skin surface, which can lead to performance degradation or device damage due to significant skin deformation or external forces from skin-object interactions. This work addresses this challenge by developing soft, stretchable mechano-acoustic sensing platforms where all sensing components are not directly subjected to skin movement or deformation. Instead, this design allows cardiovascular pulse waves to propagate through a hollow, flexible microchannel, to vibrate the piezoresistive sensing element. Experimental studies demonstrate a complete wireless sensing system capable of detecting pulse waves and heart rates, with results consistent with those of commercially available devices. The proposed sensing concept allows for the develop of other wireless and flexible sensing systems such as a flexible air-channel pad for detecting swallowing patterns from users’ laryngeal movements, facilitating a non-invasive and remote platform for potential monitoring, and assessment of dysphagia.

Robot-assisted microinjection has been widely implemented in the field of experimental biology research. Force perception is more accurate than visual feedback in determining the state of interaction between the micropipette and the biological sample. The existing micro-force sensors are difficult to directly combine with micropipettes to fully utilize their capabilities. This paper develops a new integrated force-sensing microinjector with both micro-force sensing and micropipette carrying functions using a symmetrical compliant guide mechanism and highly sensitive semiconductor strain gauges. Overload protection is considered in the structure design of the sensor, which is beneficial in reducing damage caused by displacement overshot due to misuse. The mechanical performance of the proposed dual-interval force sensing device is verified through theoretical derivation, simulation analysis, and experimental testing. The sensitivity, resolution, accuracy, dynamic response, stability, and repeatability of the sensor are investigated and evaluated in the established experimental platform. Finally, puncture experiments are conducted on zebrafish larvae and crab eggs using the proposed force-sensing microinjector. The results indicate that the sensor is effective in recording force signals during penetration of the sample.