Advanced Sensor Research最新文献

Glycoprotein 88 (GP88) is a secreted biomarker overexpressed in various cancers, as well as neurological and inflammatory diseases. In this study, we introduce the first disposable electrochemical immunosensor for GP88 detection that is built on a screen-printed carbon electrode modified with carboxylated multi-walled carbon nanotubes. Surface carboxyl groups are activated using EDC/NHS chemistry, followed by covalent attachment of streptavidin to facilitate the capture of a biotinylated anti-GP88 antibody. When exposed to GP88, the sensor shows a 19% increase in charge-transfer resistance, used as the sensor's response parameter, indicating a binding between GP88 and its biorecognition element. Reproducibility is confirmed with a relative standard deviation (RSD) of 4.05% across multiple trials, demonstrating reliable sensor fabrication. The limit of detection was estimated at 52 ng/mL, with a linear range of 25500 ng/mL. The specificity of the sensor is verified by exposing the bio-electrode to a human serum albumin control, which causes negligible signal changes. We have also concluded that maintaining streptavidin hydration during bio-electrode assembly is critical for preserving biotin-binding activity. To our knowledge, this is the first reported electrochemical platform for direct quantification of GP88, providing groundwork for further optimization of GP88 detection in an electroanalytical manner.

Novel cryptocyanine-based DNA-binding fluorescent probes were developed by introducing side chains with varying polarity to the dye scaffold. This structural modification improves water solubility, reduces aggregation in aqueous media, and enhances DNA binding affinity. Upon binding to DNA, the derivatives exhibit a high increase in fluorescence quantum yield, demonstrating their potential as fluorogenic DNA probes. The photophysical behavior of the dyes is systematically investigated using spectroscopic techniques, focusing on their environment-sensitive emission properties. These results highlight the importance of environmentally responsive dye scaffolds in the development of fluorogenic tools for nucleic acid detection and diagnostic applications.

Nanocomposites

An electrochemical platinum microelectrode is decorated with carbon nanotubes bearing redox-active orange polyoxovanadate octahedra. Each octahedron anchors ribbon-like aptamer chains that capture target protein biomolecules, illustrating molecular detection from a fluid sample. More details can be found in the Research Article by Kirill Monakhov and co-workers (DOI: 10.1002/adsr.202500080). Cover artwork created by Eric Vogelsberg

Urea, a nitrogenous organic compound resulting from protein metabolism, is excreted as a waste product in urine. Elevated blood urea levels are associated with severe health conditions, including chronic kidney disease (CKD) and liver failure. Thus, monitoring urea levels is essential for CKD patients and individuals with metabolic disorders that heighten the risk of CKD. While existing diagnostic technologies offer high sensitivity and specificity, they are often expensive, require skilled operators, involve lengthy processing times, and are typically invasive and discontinuous. To address these challenges, researchers have developed various biosensor systems for rapid and cost-effective urea detection. This review provides a comprehensive overview of recent advancements in urea biosensing technologies, highlighting key challenges and potential solutions in biosensor design. It examines enzymatic and non-enzymatic urea biosensors, focusing on electrochemical detection techniques such as amperometry and potentiometry for enzymatic sensors and cyclic voltammetry for non-enzymatic sensors. Additionally, it explores material innovations, technological advancements, and strategies to enhance sensitivity, selectivity, portability, and stability. The integration of biosensors with IoT for real-time monitoring and their applications in medical diagnostics are also discussed.

In this modern era, wearable biosensors have emerged as a significant innovation in specialized personal healthcare. While smartphones and smartwatches today can easily measure vital signs and mobility, a new generation of wearable technology quickly emerges, allowing users to monitor their health metrics at the molecular level. Wearable electrochemical microneedle biosensors show the capability of detecting analytes and metabolites in interstitial fluid with minimal invasiveness. The use of microneedle sensing technology revolutionises biosensing techniques and opens new avenues for advancing current biosensors. In situ extraction, monitoring, and painless injection become possible through microneedle biosensors. However, there remains a need for improvement in detection accuracy and accessibility. This review begins with a discussion on the introduction and a comprehensive background of microneedle technology. It then explores different types of microneedles and fabrication methods. Various sensing modalities for microneedle biosensors, such as electrical, electrochemical, Raman, and colorimetric methods, are also discussed. Finally, the practical applications of wearable microneedle biosensors in various fields are examined, followed by a comprehensive conclusion and prospects.

In this modern era, wearable biosensors have emerged as a significant innovation in specialized personal healthcare. While smartphones and smartwatches today can easily measure vital signs and mobility, a new generation of wearable technology quickly emerges, allowing users to monitor their health metrics at the molecular level. Wearable electrochemical microneedle biosensors show the capability of detecting analytes and metabolites in interstitial fluid with minimal invasiveness. The use of microneedle sensing technology revolutionises biosensing techniques and opens new avenues for advancing current biosensors. In situ extraction, monitoring, and painless injection become possible through microneedle biosensors. However, there remains a need for improvement in detection accuracy and accessibility. This review begins with a discussion on the introduction and a comprehensive background of microneedle technology. It then explores different types of microneedles and fabrication methods. Various sensing modalities for microneedle biosensors, such as electrical, electrochemical, Raman, and colorimetric methods, are also discussed. Finally, the practical applications of wearable microneedle biosensors in various fields are examined, followed by a comprehensive conclusion and prospects.

Terahertz (THz) technology holds great promise in biomedical imaging, non-destructive testing, biosensing, and telecommunications, but its adoption is limited by weak light–matter interactions and strong dissipative losses in conventional metamaterials. To overcome these limitations, a dual strategy is introduced that combines interdigitated electric split-ring resonators (ID-eSRRs) with the complex-frequency wave (CFW) technique. Electrical gating from 0–200 V tunes the graphene Fermi level from 0.3756 to 0.6505 eV, providing a wide and continuous resonance shift for fingerprint-aligned sensing. The CFW method reconstructs loss-compensated spectra from real-frequency data, generating virtual gain and markedly sharpening resonances. Simulations show that the optimized ID-eSRR achieves a refractive index sensitivity of 196 GHz/RIU for 100 nm analytes, while CFW amplification increases the quality factor from 8.54 to 427.96, a 50.1-fold enhancement. This improvement enables reliable discrimination of DNA variants with refractive index differences as small as $$ at $$. The demonstrated approach provides a generalizable route to simultaneously enhance sensitivity and $$-factor, thereby overcoming the long-standing sensitivity–$$ trade-off and advancing the development of high-performance THz sensors for ultrasensitive biomedical diagnostics.

Metal halide perovskites (MHPs) have been proven to have excellent direct X-ray detection properties due to their high carrier lifetime product, strong X-ray absorption ability, a low electron-hole pair creation energy, and excellent charge transport properties. Millimeter-thickness polycrystalline MHPs (MPMHPs) can effectively utilize X-rays and have detection performance comparable to single-crystal MHP, and it is less difficult to synthesize. In this paper, we review the direct X-ray detectors and imagers based on MPMHPs. The basic knowledge of X-ray and direct X-ray detectors is introduced. This review focuses on describing in synthesis methods of MPMHPs and their X-ray detection performance. Furthermore, we summarize the X-ray imaging scheme and imaging application results of MPMHPs. Finally, we discuss future optimization methods in material synthesis, device optimization, and imaging applications. We hope that this review will help readers understand the basics of MPMHPs, improve detection performance, and boost imaging applications.

This study investigates how the emission mechanism (fluorescence, phosphorescence, or thermally activated delayed fluorescence, TADF) of a luminescence-quenching chemical sensor influences the sensitivity of explosives detection. Steady-state and time-resolved photoluminescence measurements were used to evaluate the quenching kinetics of representative emitters in the presence of 2,4-dinitrotoluene (DNT), a model nitroaromatic explosive. Linear Stern-Volmer behavior was observed for the fluorescent and phosphorescent emitters, whereas the TADF compound exhibited a pronounced downward deviation in steady-state measurements, arising from the simultaneous but distinct quenching of singlet and triplet exciton populations. To describe this behavior, we derived a modified Stern–Volmer formalism comprising separate relationships for the prompt and delayed fluorescence. The quenching dynamics of the TADF system were found to be strongly dependent on the intrinsic parameters $$, k_Stot and k_Ttot, with the singlet and triplet populations being quenched with different efficiencies. These insights highlight the potential of TADF luminophores to act as sensitive photoinduced electron transfer-based explosives sensors.