Biosensors and Bioelectronics最新文献

Methyl jasmonate (MeJA), a key plant hormone, plays essential roles in plant growth, development, biotic stress responses, and wound-induced defense. Monitoring dynamic changes in MeJA in situ is vital for botanical research. Herein, coupling with paper-based analytical devices, the ultra-thin flexible stainless steel sheets with the excellent flexibility and conductivity were used to develop wearable electrochemical immunosensor for in situ and continuous detection of MeJA in plants. The ultra-thin flexible stainless steel sheets were modified with conducting carbon cement, ferrocene - graphene oxide - multi-walled carbon nanotubes composites, and MeJA antibodies to construct the wearable electrochemical immunosensor, which can detect the MeJA in the range of 10 pM-100 μM, and with a limit of detection of 5.4 pM. Using this wearable electrochemical immunosensor, the MeJA content in tomato leaves under wound stimulation was detected in situ and continuously. The results showed that MeJA levels in tomato leaves increased significantly with mechanical damage. A significant difference was observed between the untreated control group (0 cm) and the mechanically damaged group (2.0 cm), confirming the sensor's capability to monitor dynamic changes in MeJA in response to stress in real-time. In all, this study not only suggested that the ultra-thin flexible stainless steel sheets with the excellent flexibility and conductivity can be used to fabricated the wearable electrochemical sensors, but also provided a novel method for continuous in situ MeJA detection, which contributed to the understanding of MeJA regulatory mechanisms in plants and advancing precision agriculture technologies.

Mycoplasma pneumoniae (M. pneumoniae), a major human respiratory pathogen, necessitates the development of rapid point-of-care testing (POCT) platforms for clinical management. However, current two-step workflows suffer from operational complexity and aerosol contamination risks. This limitation stems from CRISPR-Cas12 mediated template degradation in single-reaction systems, which compromises amplification efficiency and detection sensitivity. Here, we combined RPA and CRISPR Cas12b by leveraging the difference in their optimal temperatures to construct a novel TRACER (Thermo-activated RPA Amplification for CRISPR-Cas12b Efficient Recognition) technology. Through precise temperature modulation, TRACER sequentially executes isothermal amplification and CRISPR-mediated detection while preventing premature template cleavage, thereby maintaining optimal reaction efficiency. The platform demonstrates exceptional analytical sensitivity with a detection limit of 1 copy/μL, representing a 100-fold improvement over conventional one-pot RPA-CRISPR-Cas12a systems. Clinical validation using 195 specimens revealed diagnostic performance metrics of 99.2 % sensitivity (119/120), 100.0 % specificity (75/75), and 99.5 % accuracy (194/195). This innovative combination of single-tube reaction, field-deployable instrumentation, and cost-effectiveness establishes TRACER as an ideal POCT solution for M. pneumoniae detection in diverse clinical settings.

Wearable biochemical sensors enabling non-invasive monitoring of biomarkers in bodily fluids play a pivotal role in advancing personalized healthcare. The state-of-the-art wireless and wearable biochemical sensors still suffer from large form factors, poor detection accuracy due to sample-to-sample variation, short and weak wireless communication, and difficulty to integrate with data processing algorithm on a system level. To solve these problems, this work develops an all-range wireless and wearable biochemical sensing platform which can be integrated in a diaper for monitoring four urine biomarkers (dimethylamine, creatinine, glucose, and H⁺) with two switchable wireless modes. To simplify the circuit design and reducing the form factor of the wearable sensing platform, this work develops flexible and passive potentiometric sensing interfaces for dimethylamine and creatinine detection by developing high-performance ion-selective electrode (ISE) with customized molecularly imprinted polymers (MIPs) as ionophores. The narrowband Internet of Things (NB-IoT) far-field wireless mode enables remote, and concurrent monitoring of urine biomarkers with a working range up to tens of kilometers, while the LC resonance near-field wireless mode is capable of battery-free and intermittent detection of urine biomarkers. The wearable sensor can be easily switched between the NB-IoT far-field wireless mode and the near-field wireless mode to fit different application scenarios. The wireless sensing platform enables system level integration of the wearable biochemical sensor with a multilayer perceptron data calibration system for data auto-calibration, which reduces the errors caused by varying pH and thus improves the detection accuracy, enabling deeper AI-wearable biochemical sensor fusion for next-generation healthcare applications.

Developing a preamplification-free and sensitive clustered regularly interspaced short palindromic repeats (CRISPR)-based method is significant but still extremely challenging for microRNA (miRNA) detection. Here we present a combination of a CRISPR/Cas13a-based reaction with a lateral flow biosensor, which enables the quantitative and colorimetric readout of preamplification-free miRNA detection at room temperature. In this work, the reaction principle and the structure of the lateral flow strip are well-designed to achieve surface-enhanced Raman scattering (SERS)/colorimetric dual-signal "turn-on" response of target miRNA. The CRISPR/Cas13a Reporter is engineered with a DNA-RNA splicing structure to generate DNA cleavage products and reduce nonspecific collateral cleavage. Without the need for nucleic acid preamplification strategy, the developed CRISPR/Cas13a-driven lateral flow biosensor enables the microRNA-21 (miR-21) detection at room temperature with a readout time of 10 min and a total process time of less than 45 min, achieving an impressive limit of detection of 8.96 aM by SERS and 1 fM by visualization, respectively. Moreover, the platform demonstrated excellent recovery rates in spiked human serum samples. The proposed CRISPR/Cas13a-driven, dual-signal "turn-on"-responded lateral flow platform has the potential to simultaneously meet the requirements of convenient point-of-care visualization detection and more accurate and sensitive SERS detection of miR-21, offering a cost-effective, rapid, and reliable tool for early cancer diagnosis.

Alkaline phosphatase (ALP) is a clinically important hydrolase enzyme and a valuable biomarker for hepatobiliary diseases, metabolic bone disorders, and certain malignancies. Raman-based miniaturized sensors, particularly those employing surface-enhanced Raman scattering (SERS), have enabled ultrasensitive and selective ALP detection at femtomolar to picomolar levels in complex biological samples. This narrative review critically examines recent advances in SERS-enabled ALP sensors, highlighting hotspot engineering, nanozyme-assisted signal amplification, and microfluidic integration to achieve high-throughput, low-volume assays. It also explores the incorporation of artificial intelligence algorithms for real-time spectral interpretation and discusses the potential for integrating these systems with fifth and sixth generation (5G/6G) wireless networks for rapid, cloud-based diagnostics. In addition, this review outlines current challenges, including substrate reproducibility and standardization issues, and proposes strategies to enhance clinical translation. Collectively, these developments are transforming ALP sensing by enabling decentralized, intelligent, and personalized diagnostic platforms, which hold promise for advancing precision healthcare and improving patient outcomes.