Mikkelsenwalter8562

As most of the conclusive results come from Raman spectroscopy, this study shows the potential of Raman spectroscopy as a key technique in the upcoming new explorations of Mars materials by the Rosalind Franklin rover (Exomars2022 mission from ESA) and the Perseverance rover (Mars2020 mission from NASA), where Raman spectrometers are mounted for the first time in an extra-terrestrial research in the field.Since coronavirus disease 2019 (COVID-19) started as a fast-spreading pandemic, causing a huge number of deaths worldwide, several therapeutic options have been tested to counteract or reduce the clinical symptoms of patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, no specific drugs for COVID-19 are available, but many antiviral agents have been authorised by several national agencies. Most of them are under investigation in both preclinical and clinical trials; however, pharmacokinetic and metabolism studies are needed to identify the most suitable dose to achieve the desired effect on SARS-CoV-2. Therefore, the efforts of the scientific community have focused on the screening of therapies able to counteract the most severe effects of the infection, as well as on the search of sensitive and selective analytical methods for drug detection in biological matrices, both fluids and tissues. In the last decade, many analytical methods have been proposed for the detection and quantification of antiviral compounds currently being tested for COVID-19 treatment. In this review, a critical discussion on the overall analytical procedure is provided, i.e (a) sample pre-treatment and extraction methods such as protein precipitation (PP), solid-phase extraction (SPE), liquid-liquid extraction (LLE), ultrasound-assisted extraction (UAE) and QuEChERS (quick, easy, cheap, effective, rugged and safe), (b) detection and quantification methods such as potentiometry, spectrofluorimetry and mass spectrometry (MS) as well as (c) methods including a preliminary separation step, such as high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) coupled to UV-Vis or MS detection. Further current trends, advantages and disadvantages and prospects of these methods have been discussed, to help the analytical advances in reducing the harm caused by the SARS-CoV-2 virus.This work reports the simple and inexpensive fabrication of homemade paper-based carbon-printed electrodes (HP C-PEs), aiming to produce an alternative way to generate electrochemical biosensors to all and promoting their wide use. This is especially important in times of pandemics, considering the excellent features of electrochemical biosensing, which may ensure portability, low-cost and quick responses. HP C-PEs were fabricated using a standard cellulose filter paper that was first modified with wax, to make it hydrophobic. Then, the electrodes were manually printed on top of this cellulose/wax substrate. The electrodes were designed by having standard configurations for potentiometric and electrochemical readings, combining two or three electrodes. In general, both electrode systems showed excellent electrochemical and mechanical features, which were better in specific cases than commercial devices. The 3-electrode system displayed high current levels with low peak-to-peak potential separation, yielding highly stable signals after consecutive electrode bending that corresponded to high active areas. The possibility of modifying the devices with polymers produced in-situ was also explored and proven successful, providing also advantageous features when compared to other devices. The 2-electrode system was also proven highly stable and capable of subsequent use in potentiometric sensing development. Overall, the fabrication process of the 2- and 3-electode systems described herein may be employed in laboratories to produce successful electrochemical biosensors, with the final devices displaying excellent electrochemical and mechanical features. This procedure offers the advantages of being simple and inexpensive, when compared to other commercial devices, while using materials that are promptly available and that may undergo a worldwide use.C-reactive protein, cystatin C, myoglobin, and D-dimer represent the inflammatory or thromboembolic status of the patient and play important roles in early diagnostics of acute myocardial infarction. Futibatinib inhibitor Each protein can indicate some health problems, but their simultaneous detection can be crucial for differential diagnostics. The express analysis of these proteins in a small drop of plasma was developed using magnetic beads. The suggested method is based on immunomagnetic extraction of the target analyte from plasma samples and its simultaneous labelling by fluorescent dye. Reaction time was optimized for quantification of cardiac biomarkers in the spike solutions and human plasma samples. In this paper, we developed a one-protein detection technique for each cardiac biomarker and united it to a four-protein facility using an automatic platform. The proposed technique requires only 17 μL of the human plasma and takes 14 min for four-protein measuring. The suggested technique covers concentration difference by more than two orders of magnitude and demonstrates analytical applicability by measurements of human plasma samples of 16 volunteers.Herein we describe the design and synthesis of novel artificial peptides mimicking the plastoquinone binding niche of the D1 protein from the green photosynthetic alga Chlamydomonas reinhardtii, also able to bind herbicides. In particular, molecular dynamics (MD) simulations were performed to model in silico the behaviour of three peptides, D1Pep70-H, D1Pep70-S264K and D1Pep70-S268C, as genetic variants with different affinity towards the photosynthetic herbicide atrazine. Then the photosynthetic peptides were functionalised with quantum dots for the development of a hybrid optosensor for the detection of atrazine, one of the most employed herbicides for weed control in agriculture as well as considered as a putative endocrine disruptor case study. The excellent agreement between computational and experimental results self consistently shows resistance or super-sensitivity toward the atrazine target, with detection limits in the μg/L concentration range, meeting the requirements of E.U. legislation.Herein, we have synthesized Gd2O3Yb,Er@UiO-66-NH2 (UiO-66-NH2 represent a zirconium-based metal organic framework [Zr6O4(OH)4(ata)12], ata 2-aminoterephthalate) core-shell composites to develop an upconversion fluorescent nanoprobe for efficient detection of trace methylene blue (MB) and ferrous ions (Fe2+). Due to the fluorescence of the nanoprobe can be quenched by MB based on inner filter effect, but gradually recover when contact with ·OH, which is generated from the reaction between H2O2 and Fe2+, we have achieved the detection of Fe2+. The detection linear range is from 1.78 to 15.8 μM, and the limit of detection (LOD) is 0.071 μM. link2 Besides, in this process, we also simultaneously realize the detection of MB. The linear range of MB turn-off detection is 0-42.6 μM, and the LOD is 0.41 μM. To our knowledge, no example of using upconversion fluorescence probe for continuous detection of trace MB and Fe2+ has been reported for now, and test results are superior compared with most reported Fe2+ probes. Moreover, the combinations of upconversion nanoparticles (UCNPs) and the metal-organic frameworks (MOFs) have enhanced the selectivity and sensitivity of the probe towards MB and Fe2+. link3 Therefore, we believe the designed upconversion fluorescent nanoprobe is a promising efficient tool in detecting MB and diagnose Fe2+ related diseases in the future.Reduced glutathione (GSH) and the oxidized glutathione (GSSG) are well-known biomolecules in the main constituents of intracellular redox homeostasis system. A rapid, accurate measurement of cellular GSH and GSSG is quite needed in investigating important biochemical events. In this work, we present a novel and sensitive method to monitor intracellular GSH and GSSG concentrations by a portable surface-enhanced Raman spectroscopy (SERS) technique. We introduced a reduction-sensitive reaction-type Raman probe, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) to initiate GSH reduction, itself concomitantly converts to 2-nitro-5-thiobenzoic acid (TNB) to release a strong SERS signal. In a convenient way of inorganic salt MgSO4 induced aggregation of silver nanoparticles substrate, we easily implemented a good discrimination between DTNB and TNB, and a quantitative measurement of GSH and GSSG with a high sensitivity of 10 nM. This SERS method proved its feasible applicability in rapidly and sensitively monitoring GSH depletion behaviors of some notorious alkylating agents, i.e., sulfur mustard and nitrogen mustards in ex vitro or in vitro (cellular response). This SERS method may be very worthwhile in cellular detoxication event via the GSH approach and other GSH involved biomedical researches.In this paper, holey nitrogen-doped graphene aerogel (HNGA) was synthesized and applied to the concurrently electrochemical determination of small biological molecules including ascorbic acid (AA), dopamine (DA) and uric acid (UA). Firstly, holey graphene hydrogel was synthesized by the hydrothermal reaction in the presence of H2O2, which subsequently was lyophilized and further annealed in the mixed gas of ammonia and argon to obtain HNGA. Electron microscopy characterization exhibited a great number of nanopores formed on the basal surface of graphene sheets, and HNGA possessed a hierarchically porous structure. The unique structure and composition of HNGA make it an ideal material for electroanalytical application through accelerating mass and electron transfer. HNGA modified glassy carbon electrode (HNGA/GCE) displayed significantly enhanced electrochemical response to AA, DA, and UA, namely reducing overpotential, increasing current density, and improving the reversibility. The oxidation peaks of these three biomolecules can be entirely separated with evident peak potential differences which are 0.216 V (AA-DA), 0.120 V (DA-UA), and 0.336 V (AA-UA), which it allowed the determination of the three substances at the same time. This sensor shows high sensitivity for the determination of AA, DA, and UA with the detection limit of 16.7 μM, 0.22 μM, and 0.12 μM (S/N = 3), respectively. The proposed sensor was applicable for the practical sample analysis as well and desirable recovery was obtained.In detecting infectious diseases, such as coronavirus 2019 (COVID-19), real-time reverse-transcription polymerase chain reaction (RT-PCR) is one of the most important technologies for RNA detection and disease diagnosis. To achieve high quality assurance, appropriate positive and negative controls are critical for disease detection using RT-PCR kits. In this study, we have found that commercial kits often adopt DNAs instead of RNAs as the positive controls, which can't report the kit problems in reverse transcription, thereby increasing risk of the false negative results when testing patient samples. To face the challenge, we have proposed and developed the chemically modified RNAs, such as phosphoroselenaote and phosphorothioate RNAs (Se-RNA and S-RNA), as the controls. We have found that while demonstrating the high thermostability, biostability, chemostability and exclusivity (or specificity), both Se-RNA and S-RNA can be fine templates for reverse transcription, indicating their potentials as both positive and negative controls for RT-PCR kits.