Construction of a Colorimetric and Near-Infrared Ratiometric Fluorescent Sensor and Portable Sensing System for On-Site Quantitative Measurement of Sulfite in Food.

Sulfites play imperative roles in food crops and food products, serving as sulfur nutrients for food crops and as food additives in various foods. It is necessary to develop an effective method for the on-site quantification of sulfites in food samples. Here, 7-(diethylamino) quinoline is used as a fluorescent group and electron donor, alongside the pyridinium salt group as an electron acceptor and the C=C bond as the sulfite-specific recognition group. We present a novel fluorescent sensor based on a mechanism that modulates the efficiency of intramolecular charge transfer (ICT), CY, for on-site quantitative measurement of sulfite in food. The fluorescent sensor itself exhibited fluorescence in the near-infrared light (NIR) region, effectively minimizing the interference of background fluorescence in food samples. Upon exposure to sulfite, the sensor CY displayed a ratiometric fluorescence response (I447/I692) with a high sensitivity (LOD = 0.061 µM), enabling accurate quantitative measurements in complex food environments. Moreover, sensor CY also displayed a colorimetric response to sulfite, making sensor CY measure sulfite in both fluorescence and colorimetric dual-signal modes. Sensor CY has been utilized for quantitatively measuring sulfite in red wine and sugar with recoveries between 99.65% and 101.90%, and the RSD was below 4.0%. The sulfite concentrations in live cells and zebrafish were also monitored via fluorescence imaging. Moreover, the sulfite assimilated by lettuce leaves was monitored, and the results demonstrated that excessive sulfite in leaf tissue could lead to leaf tissue damage. In addition, the sulfate-transformed sulfite in lettuce stem tissue was tracked, providing valuable insights for evaluating sulfur nutrients in food crops. More importantly, to accomplish the on-site quantitative measurement of sulfite in food samples, a portable sensing system was prepared. Sensor CY and the portable sensing system were successfully used for the on-site quantitative measurement of sulfite in food.

Engineered biocontainable RNA virus vectors for non-transgenic genome editing across crop species and genotypes.

CRISPR/Cas genome-editing tools provide unprecedented opportunities for basic plant biology research and crop breeding. However, the lack of robust delivery methods has limited the widespread adoption of these revolutionary technologies in plant science. Here, we report an efficient, non-transgenic CRISPR/Cas delivery platform based on the engineered tomato spotted wilt virus (TSWV), an RNA virus with a host range of over 1000 plant species. We eliminated viral elements essential for insect transmission to liberate genome space for accommodating large genetic cargoes without sacrificing the ability to infect plant hosts. The resulting non-insect-transmissible viral vectors enabled effective and stable in planta delivery of Cas12a and Cas9 nucleases as well as adenine and cytosine base editors. In systemically infected plant tissues, the deconstructed TSWV-derived vectors induced efficient somatic gene mutations and base conversions in multiple crop species with little genotype dependency. Plants with heritable, bi-allelic mutations could be readily regenerated by culturing the virus-infected tissues in vitro without antibiotic selection. Moreover, we showed that antiviral treatment with ribavirin during tissue culture cleared the viral vectors in 100% of regenerated plants and further augmented the recovery of heritable mutations. Because many plants are recalcitrant to stable transformation, the viral delivery system developed in this work provides a promising tool to overcome gene delivery bottlenecks for genome editing in various crop species and elite varieties.

Plant negative-stranded RNA virus biology and host interactions revitalized by reverse genetics.

Our understanding of the biology and pathogenesis of plant negative-stranded RNA viruses (NSVs) has lagged behind those made with positive-stranded RNA and DNA virus counterparts. This tardiness is mainly due to the lack of reverse genetics tools for NSV genome engineering for many years. The eventual establishment and application of recombinant systems with diverse plant NSVs has provided renewed momentum for investigations of these important viral pathogens. In this review, we summarize the recent advances in plant NSV reverse genetics systems, highlighting the general principles and the uniqueness of each system and emphasizing important considerations for strategy designing. We also provide a brief overview of the insights about NSV morphogenesis, movement, and virus-host interactions gained from reverse genetics-enabled studies.

Facile synthesis of nitrogen-doped reduced graphene oxide/nickel ferrite hybrid nanocomposites with superior electromagnetic wave absorption performance in the X-band.

In this work, nitrogen-doped reduced graphene oxide/nickel ferrite (NRGO/NiFe2O4) hybrid nanocomposites were synthesized by a one-pot hydrothermal method. Results manifested that the as-synthesized NiFe2O4 nanoparticles displayed hexagonal morphology with a mean size of 40 nm. Moreover, it was found that the entangled structure consisting of crumpled RGO and hexagonal NiFe2O4 nanoparticles was well constructed in the as-fabricated hybrid nanocomposites. Furthermore, the additive volumes of hydrazine hydrate and filler loadings had significant influences on the electromagnetic wave (EMW) absorption properties of obtained nanocomposites. Remarkably, the NRGO/NiFe2O4 hybrid nanocomposite with 15 mL additive volume of hydrazine hydrate showed the optimal reflection loss of -54.4 dB at 9.2 GHz (X band) under a matching thickness of 2.2 mm and maximum absorption bandwidth of 4.5 GHz (13.5-18 GHz) at a very thin thickness of only 1.5 mm. The dual absorption peaks located at the low and high frequency regions could be achieved by facilely modulating the matching thicknesses. In addition, the underlying EMW absorption mechanisms were uncovered. Therefore, our results could shed light on the design and fabrication of graphene-based dielectric/magnetic hybrid composites as light-weight and high-efficiency EMW absorbers.

[An Emerging Simulation Method Used in System Simulation of Flow Chamber of Hematology Analyzer].

In fluid flow field analysis, the common simulation method is 1-D simulation or 3-D simulation, In order to analyze blood fluid system more quickly and accurately and choose the appropriate sample tube at the beginning of design for the system, this paper adopts a recently emerging 1D-3D simulation method to make simulations of flow chamber subsystem. Respectively using Flow master and ANSYS system modeling, use MpCCI connects the two parameter coupling, realize the sheath fluid velocity of research. The software can meet the needs of design and analysis of the Hematology Analyzer fluid system. In this paper, the method of co-simulation for medical apparatus and instruments of Hematology Analyzer fluid system development provides a new method, has important significance on the subsequent simulation.