Analysis & sensing最新文献

Lipid droplets are essential for cellular lipid storage, playing critical roles in cellular lipid metabolism. Although lipid droplets have drawn intense research in recent years, much remains to be uncovered about the roles of this organelle in biology. Lipid droplet indicators exhibiting large Stokes shifts and improved brightness are therefore in demand. We report two asymmetric BODIPY derivatives, BoL1 and BoL2 bearing a benzothiazole group at the 6-position, which led to bathochromic shifts of 62 nm for BoL1 and 37 nm for BoL2 in fluorescence emission when compared to the reference molecules without the benzothiazole group. The incorporation of the benzothiazole moiety also resulted in a large Stokes shift of 40 nm. BoL1 and BoL2 have been demonstrated to operate as lipid droplet indicators in both confocal and STED imaging. BoL2 showed particularly good cellular retention and was further applied to explore the impact of cellular starvation on the trafficking of lipid droplets.

The cover feature image illustrates two mail devices, drones (representing sprayed microdroplets) and in-person (representing bulk phase), to deliver a letter (representing the Petasis reaction involving aldehydes, arylboronic acids and amines) in sharply different efficiencies. This study supplies not only a mild, efficient and environmentally friendly methodology to constructing aryl amines in organic community but also a useful derivatization strategy for highly sensitive mass spectrometric detection of arylboronic acids and aryl aldehydes. More information can be found in the Research Article by Heyong Cheng, Jiannan Sun, and co-workers.

The cover picture shows a printed 96-microwell paper-based sensor array depicting various color patterns upon changing pH conditions, which enables the prediction of pH values below the decimal point in human sweat by imaging analysis and pattern recognition techniques. More information can be found in the Research Article by Yui Sasaki, Xiaojun Lyu, and Tsuyoshi Minami .

Invited for this month's cover are is the collaborating group of Prof. Minami at The University of Tokyo. The cover picture shows a printed 96-microwell paper-based colorimetric sensor array to detect pH changes below the decimal point in human sweat. More information can be found in the Research Article by Yui Sasaki, Xiaojun Lyu, and Tsuyoshi Minami.

Due to their important roles in medicine, the product of the Petasis reaction has attracted extensive interest in pharmaceutical, medical and chemical communities. Traditional three-component Petasis methods normally use various catalysts under harsh conditions (high temperature, microwave, etc.) for long reaction times. In this study, we developed a green and highly efficient microdroplet method for accelerating the Petasis reaction, which obtain good yields without the need of any catalysts under mild reaction conditions. The Petasis reaction in microdroplets was suitable for a variety of salicylaldehydes, arylboronic acids and amines. The Petasis reaction in microdroplets was accelerated by approximately 4 orders of magnitude by comparing the measured rate constants in bulk. Further, a scaled-up amount of 0.8 g h⁻¹ was achieved for the Petasis reaction in microdroplets. This study supplies not only a high-efficiency and environment-friendly methodology to constructing aryl amines in organic community but also a useful derivatization strategy for highly sensitive mass spectrometric detection of arylboronic acids and aryl aldehydes.

Among the many biological imaging techniques, magnetic resonance imaging (MRI) has been widely adopted for biomedical and clinical diagnostic applications, because of its ability to image deep tissues with high spatiotemporal resolution. Bioresponsive contrast agents are the key to expanding the diagnostic potential of MRI by providing anatomical information and discerning biochemical activity. Recent developments in the field of responsive and gadolinium-based agents have resulted in novel complexes that can sense their chemical microenvironments and thus study various functional processes in the tissue. Herein, we discuss the design and use of Gd(III)-based and bioresponsive MRI contrast agents for specific biological markers such as Ca(II) and Zn(II) cations and zwitterionic amino acid neurotransmitters. Combining their basic physicochemical characteristics with aspects that should be considered for their use in vivo would achieve the desired sensing features and enable their applications in functional molecular imaging to visualize essential biological processes.

The cover image illustrates the binding of a group of DNA aptamers selected to recognize the spike protein (S-protein) of SARS-CoV-2, the virus that causes COVID-19. The binding affinity for several key variants of the S-protein and the degree of overlapping of the binding sites of the aptamers on the S-protein have been comparatively examined. The design was created with Biorender.com. More information can be found in the Research Article by John D. Brennan, Yingfu Li, and co-workers.

The cover feature image shows a two-dimensional (2D) colorimetric carbon dioxide (CO₂) sensor composed of a gas-permeable polypropylene film (25 μm thick) and a signal transduction hydrogel layer (30 μm thick). The hydrogel layer contained a pH sensitive chromoionophore to indicate the CO₂ induced pH change, and a cationic amine to further capture CO₂ through the carbamate formation reaction. With this 2D colorimetric CO₂ optode, the CO₂ release from yeast-catalyzed flour fermentation was successfully monitored. More information can be found in the Research Article by Jingying Zhai, Xiaojiang Xie, and co-workers.

The cover image illustrates the principle of a newly developed chemiluminescence (CL) microfluidic paper-based analytical device (μPAD) that enables highly sensitive detection of any catalytic process in which H₂O₂ is produced. Through the use of a new, sensitive CL luminophore cell phone camera detection allows quantification on-site with the same sensitivity as afforded through a CCD camera in the lab. One-step reactions to time the catalytic reactions can easily be realized through a moveable barrier if desired. Lactate is detected with μM detection limits and three orders of magnitude dynamic range in sweat, the luminophore reaches a pM detection limit. Cover design by Simone Rink.  More information can be found in the Research Article by Antje Baeumner and co-workers .

The front cover represents a wearable biosensor for the digitalization of lactate in sweat during sport activity. The biosensor is integrated into a microfluidic system for continue lactate monitoring, producing reliable real-time profiles. Outcomes: Real-time sweat lactate assessment is a potential proxy of personalized training strategies in cycling. More information can be found in the Research Article by Maria Cuartero, Gaston A. Crespo, and co-workers.