Erichsenclemmensen7024

The developed system was further applied to the metabolomic analysis of various prokaryotic and eukaryotic microorganisms. Differences due to culture media and metabolic phenotypes could be observed when comparing the metabolomes of conventional and non-conventional yeast. Furthermore, almost all Kluyveromyces marxianus metabolites could be detected with moderate reproducibility (CV less then 40%, among independent extractions), where 41 metabolites were detected with very high reproducibility (CV less then 15%). In addition, the accuracy was validated via a spike-and-recovery test,and 78 metabolites were detected with analyte recovery in the 80-120% range. Together these results establish ion-pair free metabolic profiling as a comprehensive and precise tool for data-driven bioengineering applications.Many methods have been reported to detect Cryptosporidium parvum (C. parvum) oocysts in the water environment using monoclonal antibodies. Herein, we report the use of DNA aptamers as an alternative ligand. We present the highly sensitive detection of C. parvum oocysts in wastewater samples based on aptamer-conjugated magnetic beads. A previously selected DNA aptamer (R4-6) that binds to C. parvum oocysts with high affinity and selectivity was rationally truncated into two minimer aptamers (Min_Crypto1 and Min_Crypto2), and conjugated to micro-magnetic beads. In flow cytometry tests with phosphate buffer, river water, and wastewater samples, both the minimers showed improved affinity and specificity toward C. parvum oocysts than the parent R4-6. Selleck ARS853 Moreover, Min_Crypto2 showed higher affinity to its target than the parent aptamer when testing in wastewater, indicating superior binding properties in a complex matrix. Using a fluorescence microplate-based assay, and when incubated with different numbers of oocysts, Min_Crypto2 showed a limit of detection as low as 5 C. parvum oocysts in 300 μL of wastewater. Results described here indicate that Min_Crypto2 has superior specificity and sensitivity for the detection of C. parvum oocysts, and has a strong potential to be used successfully in a sensor.The core-shell composites were first prepared by surface modification of silica spheres with two-dimensional MOF-FDM-23 nanosheets via a simple approach. The successful immobilization of 2D MOF-FDM-23 on the silica (2D MOF-FDM-23@silica) was confirmed by series of method including elemental analysis, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FT-IR) transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and the Brunauer-Emmett-Teller (BET). The obtained material showed excellent separation performance for multiple polar compounds such as sulfonamides, alkaloids, antibiotic and amino acid compounds etc. In addition, it was found to be superior to most reported MOF-based stationary phases in terms of separation performance, preparative reproducibility and chromatographic stability. The reproducibility of material preparation was demonstrated by the difference in retention time of the same mixture on three batches of the material at different times. The relative standard deviation (RSD) of the retention time for preparation repeatability was found to range from 0.5% to 1.4%. In short, the core-shell composite material prepared by this method broadened the application of MOF-based composites as chromatography stationary phase, and significantly developed the field of 2D MOF nanosheets in chromatography.An ultrasensitive immunosensor based on acetylene black (AB)/epoxy-substituted-poly(pyrrole) polymer (EpxS-PPyr) composite coated disposable indium tin oxide (ITO) electrode was fabricated for interleukin 6 (IL 6) detection. The EpxS-PPyr polymer was a promising matrix material to increase the loading capacity of immunosensor owing to its large surface area and abundance of epoxy groups. EpxS-PPyr polymer was synthesized by an esterification reaction and used to attach IL 6 receptor owing to its excellent biocompatibility and good conductivity. The electrochemical signals of the electrodes during the immunosensor fabrication were performed with electrochemical impedance spectroscopy and cyclic voltammetry techniques. Additionally, the changes formed on ITO electrode surfaces were followed by scanning electron microscopy and atomic force microscopy analyses. Under optimized conditions, the designed biosensor illustrated an ultra-sensitive signal towards IL 6 antigen at a broad concentration range from 0.01 pg/mL to 50 pg/mL. The detection limit and sensitivity were found as 3.2 fg/mL and 0.29 pg-1mLkΩ cm-2, respectively. Acceptable reproducibility, good storage-stability and excellent selectivity were found for IL 6 determination. Moreover, the proposed biosensor was applied to human serums and the recovery rates were ranged from 99.5 to 100.5 indicating acceptable accuracy. The results illustrated that this immunosensor were suitable for detection of IL 6 in clinical samples.In this study, a nanocomposite was synthesized via the formation of silver nanoparticles on fumed silica (FS@Ag) to prepare an electrochemical sensor for the determination of carbendazim (CBZ), a common pesticide. The electrochemical sensor was designed by the combination of the carbon paste electrode (CPE) with the FS@Ag nanocomposite. Based on the electrochemical sensor prepared here, a voltammetric method was developed for the determination of CBZ in water and food samples. Characterization of the nanocomposite was conducted by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray analyses. Modified electrodes were also electrochemically characterized via cyclic voltammetry and electrochemical impedance spectroscopy analyses. The FS@Ag showed electrocatalytic activity on the electrochemical oxidation of CBZ via increasing the peak currents tremendously. With the proposed method, a very low limit of detection (9.4 × 10-10 M) and a wide linear range (5.0 × 10-8 M - 3.0 × 10-6 M) were obtained for CBZ. The slope of the calibration line obtained with CPE/15FS@Ag was 194-times higher than that of bare CPE, indicating the high sensitivity of the electrochemical sensor. The performance of the electrochemical sensor has been investigated in real samples such as river water, tomato juice, orange juice, and apple juice samples. The results reveal that the electrochemical sensor prepared here can be used as an alternative to current analytical methods used for the quantification of CBZ.