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Natural protein–protein communications, such as those between transcription factors (TFs) and RNA polymerases/ribosomes, underpin cell‐free biosensing systems operating on the transcription/translation (TXTL) paradigm. However, their deployment in field analysis is hampered by the delayed response (hour‐level) and the complex composition of in vitro TXTL systems. For this purpose, we present a de novo‐designed ligand‐responsive artificial protein–protein communication (LIRAC) by redefining the connection between TFs and non‐interacting CRISPR/Cas enzymes. By rationally designing a chimeric DNA adaptor and precisely regulating its binding affinities to both proteins, LIRAC immediately transduces target‐induced TF allostery into rapid CRISPR/Cas enzyme activation within a homogeneous system. Consequently, LIRAC obviates the need for RNA/protein biosynthesis inherent to conventional TXTL‐based cell‐free systems, substantially reducing reaction complexity and time (from hours to 10 minutes) with improved sensitivity and tunable dynamic range. Moreover, LIRAC exhibits excellent versatility and programmability for rapidly and sensitively detecting diverse contaminants, including antibiotics, heavy metal ions, and preservatives. It also enables the creation of a multi‐protein communication‐based tristate logic for the intelligent detection of multiple contaminants. Integrated with portable devices, LIRAC has been proven effective in the field analysis of environmental samples and personal care products, showcasing its potential for environmental and health monitoring. [ABSTRACT FROM AUTHOR]

A light-addressable potentiometric sensor (LAPS) is a semiconductor electrochemical sensor based on the field-effect which detects the variation of the Nernst potential on the sensor surface, and the measurement area is defined by illumination. Thanks to its light-addressability feature, an LAPS-based chemical imaging sensor system can be developed, which can visualize the two-dimensional distribution of chemical species on the sensor surface. This sensor system has been used for the analysis of reactions and diffusions in various biochemical samples. In this review, the LAPS system set-up, including the sensor construction, sensing and substrate materials, modulated light and various measurement modes of the sensor systems are described. The recently developed technologies and the affecting factors, especially regarding the spatial resolution and temporal resolution are discussed and summarized, and the advantages and limitations of these technologies are illustrated. Finally, the further applications of LAPS-based chemical imaging sensors are discussed, where the combination with microfluidic devices is promising. [ABSTRACT FROM AUTHOR]

Objective: Rising concerns over wellness and aging have heightened the demand for convenient and efficient on-site health monitoring and disease screening. Current research, focused on specific biomarker detection, often neglects the complexities of sample matrix interference and the absence of a comprehensive, automated platform. To address these issues, we have developed a universal, fully automated analyzer for multifaceted, on-site biochemical analysis of body fluids., Methods: This analyzer integrates automated sample pretreatment, automatic dilution, detection, and self-cleaning functionalities seamlessly. It is designed to detect a wide range of analytes, from small molecules to macromolecules, including ions and proteins, utilizing spectrophotometric sensing. After optimization, the analyzer achieves performance comparable to traditional Enzyme-Linked Immunosorbent Assay (ELISA), while significantly expanding its detection range through automated dilution., Results: Demonstrations of small molecule detection include the simultaneous assessment of citric acid (CA) and oxalic acid (OA) in urine, achieving recovery rates between 96.65%-106.42% and 93.13%-112.50%, respectively. For protein detection, the analyzer successfully identified Cyfra21-1 in saliva with a recovery rate of 104.93%-111.31%. The pre-treatment process requires only 8.8 minutes, showing enhanced recovery rates for CA and OA at 97.8% and 97.6% respectively, which are superior and more rapid than manual methods., Conclusion: The exemplary pretreatment and detection performance of the analyzer underlines its effectiveness in multifaceted, on-site biomarker detection, establishing it as a promising and versatile tool for disease screening and health monitoring., Significance: This analyzer offers a powerful technological solution for on-site fluid testing, advancing community health care by facilitating more reliable and rapid diagnostics.

Regioselective methods to access alkylated tetrazoles still remain a challenging goal. Herein, we describe a novel regioselective protocol for N 2 -arylation of tetrazoles with diazo compounds using inexpensive Al(OTf) 3 . This reaction could be conducted under mild conditions to access a diverse array of alkylated tetrazoles with 2-substituted tetrazoles as the major products, demonstrating a comprehensive range of substrate compatibility and excellent functional group compatibility. Mechanistic studies revealed a carbene-free process in this reaction procedure. Furthermore, the scale-up reaction and transformations of the N 2 -arylation of tetrazole products demonstrated the potential of this strategy.

Malnutrition is a common complication in children with cancer. Cancer treatment and malnutrition can disrupt gut microbiome diversity and composition. The gut microbiome is of broad interest to better understand the mechanisms of malnutrition in cancer therapy. This study aimed to compare the gut microbiome between children with solid tumors postchemotherapy and healthy controls, and investigated the association of the putative microbiome differences with diet. Study participants were 27 children (7-18 years) with solid tumors within the first year after the completion of chemotherapy and 22 healthy controls. The study groups did not have a statistically significant difference in age, race, sex, and body mass index. At study intake, the participants completed the Block Kids Food Screener for dietary intakes in the past week. Fecal specimens were collected and analyzed for the gut microbiome. The cancer and control groups differed in gut microbial β-diversity and abundance analyses. The macronutrient intakes such as carbohydrates, fiber, beta-carotene, and vitamin B6 were positively associated with α-diversity. Children with adequate vitamin B6 had a higher Chao1 diversity index than children with inadequate or excessive intake ( p  = 0.0004). Children with excessive selenium intake had a trend for higher Pielou's_e index than children with inadequate intake ( p  = 0.091). Maintaining a healthy gut microbiome is critical among children with cancer. This study provides new insights on the linkages between dietary intakes and the gut microbiome in children with solid tumors postchemotherapy. These findings, if replicated in future independent studies, may help anticipate malnutrition and plan for personalized nutrition approaches during chemotherapy in pediatric cancers.