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Separation and identification of chiral enantiomers play an increasingly important role in many fields like pharmaceutical production, preparation of chemical intermediates and biochemistry. Although there are multiple methods for obtaining a single enantiomer, chiral chromatographic separation is still considered to be one of the most efficient methods. Among the numerous chiral separation materials, cellulose and its derivatives, with strong chiral recognition ability, large loading capacity and easy to functionalization, have been presented excellent enantioseparation performance, which reveals their great prospect in chiral separation. In this review, the types of cellulose derivatives, preparation of cellulose-functionalized chiral stationary phases and their application in chiral chromatographic separation in recent years were systematically summarized, and we hope to provide a useful reference for researchers working in chiral separation and inspire new discoveries in the field of cellulose-functionalized chiral separation materials.Diagnostic tools play significant roles in the fight against COVID-19 and other pandemics. Existing tests, such as RT-qPCR, have limitations including long assay time, low throughput, inadequate sensitivity, and suboptimal portability. Emerging biosensing technologies hold the promise to develop tests that are rapid, highly sensitive, and suitable for point-of-care testing, which could significantly facilitate the testing of COVID-19. Despite that, practical applications of such biosensors in pandemics have yet to be achieved. In this review, we consolidate the newly developed diagnostic tools for COVID-19 using emerging biosensing technologies and discuss their application promise. In particular, we present nucleic acid tests and antibody tests of COVID-19 based on both conventional and emerging biosensing methods. We then provide perspectives on the existing challenges and potential solutions.This study presents a novel, single-use electrochemical biosensor for the leptin biomarker, which may have potential use for early diagnosis of childhood obesity. The graphite paper working electrode was used for the first time in impedimetric biosensors. Brequinar nmr All immobilization procedure, investigation of the optimal parameters and characterization of biosensors were followed and evaluated using Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV). The Scanning Electron Microscope (SEM) was utilized to visualize the morphology of the electrode surface during the immobilization steps of the immunosensor. Moreover, the characterization of the interactions between anti-leptin and leptin was investigated by using Single Frequency Technique (SFI). The applicability of the designed biosensor for real serum samples was tested for clinical use. It was observed that the biosensor allows high sensitivity in the analyte detection (leptin) in real serum samples. Moreover, it was suggested that the developed biosensor presents advantages such as long shelf life (5% loss of activity after 8 weeks and 60% loss after 10 weeks), ability to determine analyte concentrations at picogram level (0.2 pg mL-1 -20 pg mL-1), low limit of detection (0.00813 pg mL- 1), reproducibility, reusability (12 times) and high sensitivity.The forensic analysis of inorganic gunshot residues (IGSR) involves analytical measurements from samples taken from skin and other substrates. The standard practice for IGSR analysis recommends the use of Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS) to identify the gunshot residues using combined information of the particle’s morphology and elemental composition. However, the current deficit on IGSR standard reference materials (SRM) limits the optimization of SEM-EDS for modern, lead-free ammunition and the development of emerging analytical techniques. This study aims to enhance existing capabilities by producing tailor-made microparticle suspensions that can be used for the quality control of GSR analysis, validation of existing and emerging methods, interlaboratory testing, and systematic transfer and persistence studies. To fill this gap, IGSR microparticle standards were developed by discharging various leaded and lead-free primers under controlled conditions and creating suspensions in an organic medium, then evaluated for homogeneity and stability of morphology and elemental composition. The IGSR microparticles suspensions were evaluated by three analytical techniques-SEM-EDS, Laser-Induced Breakdown Spectroscopy (LIBS) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) -to characterize the elemental composition and particle morphology. The ICP-MS digestion method was validated for these novel IGSR microparticle suspensions, and figures of merit and ruggedness testing are reported. The standard demonstrated stability in its dry and suspension forms, providing versatility for use in multiple types of analytical methods and substrates. This research is anticipated to assist forensic and environmental scientists by providing IGSR standards that can strengthen research, expand access to new detection techniques, and enhance laboratories’ cross-validation and quality assurance.A new hydrophobic deep eutectic solvent (DES) composed of thymol and vanillin (11) was prepared and used as the extraction solvent in vortex-assisted emulsification liquid-liquid microextraction of 16 pesticides in olive oil before GC-μECD analysis. Due to the complexity of oil samples, a DES-based liquid-liquid solvent system (n-hexane/acetonitrile/DES) was developed to achieve an effective clean-up. Among the four examined hydrophilic DESs, [choline chloride][urea] led to improved sensitivity, and clean chromatograms with low noise and drift from the sample matrix. Besides, the effect of the significant factors such as extraction solvent volume, pH, ionic strength, and vortex time was investigated. At the optimized conditions, the validation parameters such as linear range 0.04-250 μg kg-1, the limits of detection of 0.01-0.08 μg kg-1, intra-day, and inter-day relative standard deviations (RSDs) less then 6.8 and less then 9.7%, were obtained. This method was followed by GC-μECD and applied to determine pesticides in five olive oil samples.