Analysis & sensing最新文献

Signal amplification is critical for the detection of meaningful trace targets in the field of biomedicine, food analysis, and environmental protection. A growing number of signal amplification techniques for biosensors involving metal ions have been reported in recent years, due to the merits of simplicity, low cost, and high efficiency. This review summarizes the recent advancement and outlines the signaling methods (i. e. metal-responsive probes, metal-catalyzed reactions, regulating catalysis, and atom spectrometry) that metal ions play in biosensing as well as their applications. Besides, the potential and challenges to be addressed in the field are discussed.

Classical organic chemical reactions are essential for modern synthetic chemistry and offer valuable insights for chemical biology research. The pioneering bioorthogonal chemistry, based on the Staudinger reaction, is a prime example. However, the biocompatibility of classic “name” reactions like the Wittig reaction is still not fully explored. This versatile reaction efficiently converts carbonyl groups into olefins using phosphorus ylides, making it valuable in synthetic chemistry. Despite being in the early stages of development, the Wittig reaction and its reagents have various applications in peptide, protein, DNA, and RNA research. However, they have limitations such as low activity and efficiency, requiring organic solvents. Future directions may include developing Wittig reagents with improved biostability, simplifying the method, and creating multi-labeling methods. Improving light-activated Wittig reactions and interdisciplinary integration can further advance bioorthogonal chemistry. As technology advances, the Wittig reaction is poised to make greater contributions to molecular biology, cell biology, and biochemical modification research.

Lipidomic analysis of human serum is essential to monitor the individual's health status. Herein, we develop a facile strategy for rapid characterization of phospholipids in human serum via indium tin oxide (ITO) coated glass slide solid phase extraction MALDI mass spectrometry (ITO-SPE-MALDI-MS). Phospholipid species are retained on ITO slide via solid phase extraction owing to the unique property of the ITO material; the measurement of phospholipid species from 1 μl human serum within 2 min is achievable. A comparison of ITO-SPE strategy with conventional extraction methods was further carried out using liquid chromatography-mass spectrometry (LC-MS) and ion-mobility mass spectrometry (IM-MS), resulting in a comparable enrichment performance for the phospholipid analysis. Furthermore, rapid lipidomic profiling of serum samples from human colorectal cancer patients and cell lines was demonstrated. Our results indicate that ITO-SPE-MALDI-MS provides a higher throughput strategy for the analysis of phospholipid species in complex biological mixtures, showcasing its potential for applications in the analysis of clinical biofluids.

Antibiotic resistance presents a worldwide public health emergency, impeding the effective management of infectious diseases. Pseudomonas aeruginosa plays a substantial role as a bacterial pathogen, particularly in infections among hospitalized individuals, and those with weakened immune systems. Timely and accurate detection of antimicrobial resistance in P. aeruginosa is crucial for initiating tailored antibiotic therapy promptly, thus improving patient outcomes. Nevertheless, this endeavor encounters challenges due to the intricate and varied nature of antibiotic-resistant strains. Extensive efforts have been invested in developing sensors and instrumentations for assessing antibiotic resistance or susceptibility (AST), aiming to enable personalized patient treatment with appropriate medications. This paper focuses on recent advancements in these methodologies, utilized for evaluating the degree of antibiotic resistance or susceptibility in pathogenic bacteria. Flow cytometry, dual molecular recognition and mass spectrometry are presented as newer phenotypic AST techniques. Genomic methods and the pyocyanin detection are listed as methodologies for the detection of resistance indicators.

In cancer surgery, the precise characterisation of tissue margins is of paramount importance to ensure effective resection. However, conventional methods have inherent limitations in terms of both speed and accuracy, often necessitating labour-intensive postsurgical tissue analyses. To overcome these challenges and enhance the precision of cancer surgery, we introduced an innovative Multimodal Sensing and Imaging Platform (MSIP) equipped with advanced pH sensing capabilities. The MSIP represents the synergistic fusion of a miniaturised, flexible wire-based electrochemical pH sensor with a sensitivity of 62.4 mV per pH for real-time functional imaging. Simultaneously, it incorporates a high-speed confocal endomicroscope utilizing a 2.6 mm fibre bundle to achieve subcellular resolution in morphological imaging. The pH sensor enables continuous monitoring of dynamic changes in the tumour microenvironment, offering valuable insights. Confocal endomicroscopy provides high-resolution, real-time imaging of tumour morphology with an impressive 2.2 μm resolution. This integration not only enhances the precision of cancer surgery but also fosters a comprehensive understanding of the biological and molecular characteristics of tumours. By consolidating multiple diagnostic parameters into a unified platform, MSIP has emerged as a transformative technology poised to revolutionise our approach to cancer surgery.

Invited for this month′s cover are the collaborating groups of the Université libre de Bruxelles and Masaryk University. The cover picture shows liposomes with a fluorescent probe encapsulated to study the transmembrane transport of chloride by synthetic anion transporters via quenching of the fluorescence. More information can be found in the Concept article by Hennie Valkenier and co-workers.

Neurotransmitters are essential for electrochemical communication between neurons. Accurate detection and monitoring of neurotransmitters are crucial for comprehending the intricacies of the human nervous system. Despite their crucial role, neurotransmitters exist in the human body at low concentrations amidst other cellular components, posing challenges for their precise detection and quantification. While electrochemical detection stands as an important technique, its point-of-care diagnostic applications are constrained by complex machinery and sample preparation. To address this limitation, alternative detection strategies for neurotransmitters have been explored. This review discusses the development and principles of array-based sensors designed for facile and rapid detection of neurotransmitters. Moreover, it explores future prospects for the implementation and advancement of these techniques, envisioning a promising trajectory for improved understanding and manipulation of the human nervous system.

A prevailing scientific challenge is the accurate and sensitive detection of chemical species within complex systems. Sensor arrays are a valuable solution for many analyte classes. Guest Editors Pavel Anzenbacher, Jr. (Bowling Green State University, USA) and Elizabeth J. New (The University of Sydney, Australia) discuss the field and present the Special Collection on Optical Cross-Reactive Sensor Arrays.

In the rapidly evolving landscape of molecular imaging, super-resolution techniques emerge as indispensable tools, revolutionizing our capacity to decipher the intricacies of protein aggregation, and paving the way for molecular-level understanding of the progression of neurodegenerative disorders. In this review article we provide an overview of the diverse super-resolution imaging techniques applied to study amyloids at high resolution. We outline the strengths and limitations of each technique, offering insights into their applicability to different amyloid systems. We next delve into the diverse strategies employed for labeling amyloids in conjunction with super-resolution imaging. From small organic dyes to fluorescent proteins and advanced chemical probes, the discussion encompasses the strengths and considerations associated with each labeling method. The comparative analysis not only evaluates the impact of labeling on resolution and specificity but also highlights emerging trends and future directions in the field.

Small molecule metabolites depict a biological system‘s status and help monitor disease conditions. Surface-enhanced Raman scattering (SERS) holds considerable promise as an instant and non-destructive detection tool for biological diagnosis. With single-molecular sensitivity, molecular fingerprint and water compatible, SERS provides valuable information about chemical structures and analyte compositions, especially desirable in biological diagnosis. Design and fabrication of effective, stable SERS substrates can be one of the major research priorities to provide small-molecule tracing with high sensitivity, selectivity, and reproducibility. Significant efforts have been directed towards creating high-performance and multifunctional SERS substrates spanning from coinage metals to semiconductor materials. However, most SERS substrates are suffering from unsatisfied sensitivity for tracing small molecules such as volatile organic compounds (VOCs) and other biomarkers. This review summarized recent advances in SERS-active substrates and their sensing for small biomarker molecules, especially VOCs in diagnosis.