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The sensor revealed to be highly selective in the presence of common interferents and other widely consumed anti-inflammatory drugs. Moreover, the developed sensor reached good accuracy in wastewater and fish samples with recoveries varying from 82.3 ± 4.4 to 88.6 ± 4.5%.Particulate matter (PM) is the major environmental pollutant. Its elemental composition is routinely monitored. Inductively coupled plasma mass spectroscopy (ICPMS) is commonly applied after a PM sample has been digested by an acid during a microwave treatment. In this case, sample preparation procedure is laborious, sometimes incomplete and produces toxic waste. In this paper we show that direct sample introduction to ICPMS by laser ablation (LA-ICPMS) is of huge advantage. Minimal quantity of a sample is required for the analysis ( less then 1 cm2) and no chemical waste is produced. The study focused on the most universal and widely used quartz fibre filter samples and we show that LA-ICPMS can be successfully applied for the determination of the elemental composition of such samples. Some effort is, however, still needed to develop an autosampler for the LA-ICPMS system and to provide commercial matrix-matched standards for this application to be implemented in environment laboratories worldwide.Purification and concentration of DNA is a critical step on DNA-based analysis, which should ensure efficient DNA isolation and effective removal of contaminants that may interfere with downstream DNA amplification. Complexity of samples, minute content of target analyte, or high DNA fragmentation greatly entangles the success of this step. To overcome this issue, we designed and fabricated a novel miniaturized disposable device for a highly efficient DNA purification. The microfluidic device showed binding efficiency and elution yield of 90.1% and 86.7%, respectively. Moreover, the effect of DNA fragmentation, a parameter that has not been previously addressed, showed a great impact in the recovery step. The microfluidic system integrated micropillars with chitosan being used as the solid-phase for a pH-dependent DNA capture and release. We have showed the potential of the device in the successful purification of environmental DNA (eDNA) from river water samples contaminated with Dreissena polymorpha, an invasive alien species responsible for unquestionable economic and environmental consequences in river water basins. Additionally, the device was also able to concentrate the DNA extract from highly diluted samples, showing promising results for the early detection of such invasive species, which may allow prompt measures for a more efficient control in affected areas. Suitability for integration with downstream DNA analysis was also demonstrated through qPCR analysis of the samples purified with the microfluidic device, allowing detection of the target species even if highly diluted.A revolutionary impact on the pharmaceutical and biomedical applications has been arisen in the few years to come as a result of the advances made in magnetic nanoparticles (MNPs) research. The use of MNPs opens wide opportunities in diagnostics, drug and gene delivery, in vivo imaging, magnetic separation, and hyperthermia therapy, etc. Besides, their possible integration in sensors makes them an ideal essential element of innovative pharmaceutical and biomedical applications. Nowadays, MNPs-based electrochemical sensors have attracted great attention to pharmaceutical and biomedical applications owing to their high sensitivity, stability. Selectivity towards the target as well as their simplicity of manufacture. Therefore, this review focus on recent advances with cutting-edge approaches dealing with the synthesis, design, and advantageous analytical performance of MNPs in the electrochemical sensors utilized for pharmaceutical and biomedical applications between 2015 and 2020. The challenges existing in this research area and some potential strategies/future perspectives for the rational design of electrochemical sensors are also outlined.The free fatty acids that contain one to eight carbons (C1-C8) in biodiesel would affect the quality of biodiesel. It is still a matter of challenge to simultaneously determine the composition of C1-C8 fatty acids in seed oil and seed oil-based biodiesel. Herein, a novel method of charge derivatization coupling with direct infusion mass spectrometry (CD-DIMS) was developed for the determination of the C1-C8 fatty acids in biodiesels. A fixed-charge derivatization reagent, 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide (CMCT), was used to convert fatty acids into their cationic derivatives, which significantly improved the sensitivity and selectivity of detection. Good linearity was observed with the limits of detection (LODs) in the range of 0.0002-0.001 μg mL-1 for the investigated fatty acids. The recovery was in the range of 85.1%-101.9% and the matrix effect was within the range of 75.5-93.2%. The developed method was carried out to analyze C1-C8 fatty acids in rubber seed oil (RSO) and RSO-based biodiesels produced by different catalysts, including NaOH, TiO2, and carbodiimide. It was also applied to the dynamic monitoring of C1-C8 fatty acids in RSO and produced RSO biodiesels during the oxidation process. As results, formic acid, acetic acid, and propionic acid were detected in aged RSO and biodiesel samples. The contents of formic acid, acetic acid, and propionic acid all increased in aged RSO and biodiesels, but with different growth rates. These results demonstrated that the developed CD-DIMS method can provide a quick, accurate, and sensitive analysis of C1-C8 fatty acids in seed oil and biodiesel samples.A simple and rapid microextraction procedure is reported on the use of ionic liquid (IL) in combination with magnetic multiwalled carbon nanotubes (MMWCNTs). The procedure is based on temperature-controlled IL dispersive liquid phase microextraction (DLPME) and MMWCNTs, for selective preconcentration of N-methylcarbamate pesticides in water samples, followed by their hydrolysis in alkaline buffer, prior to being analyzed by capillary electrophoresis. The extraction procedure uses small volume of organic solvents, and there is no need for centrifugation. In the experimental approach the IL was quickly disrupted by an ultrasonic probe, heated with the temperature controlled at 90 °C and dispersed in water samples in a homogenous form. MLN2480 cost At this stage, N-methylcarbamate pesticides migrate into the IL. Then the solution was cooled and small amounts of MMWCNTs were dispersed into the sample solutions to adsorb the ionic liquid containing the analytes and phase separation was completed. The ionic liquid allowed the microextraction of the analytes and a small volume of dichloromethane (DCM) was used for elution. MMWCNTs favored the adsorption of the ionic liquid with the analytes and improved the final recovery with respect to the use of simple magnetic nanoparticles as a sorbent material. Under the optimum conditions, limit of quantifications (LOQ) were achieved in the 5.6-9.3 ng mL-1 range, with recoveries between 85.0% and 102.4%.In this manuscript, a layer of 2-methylimidazole zinc salt (ZIF-8) membrane is deposited on the surface of glassy carbon electrode (GCE) modified with platinum nanoparticles (Pt NPs) by reduction electrochemical method to obtain ZIF-8/Pt NPs/GCE, and then used for the detection of ascorbic acid (AA). The deposition of Pt NPs on the surface of GCE can not only guide the nucleation and growth of ZIF-8 membrane, but also exert a synergistic effect with it to enhance conductivity. For ZIF-8 membrane, it can increase the active area of electrode and thus improve the electrochemical response of the sensor for AA. Influence factors such as the deposition current density, deposition time on the surface morphology of the modified electrode, and the detection performance of the modified electrode during the electrochemical deposition of ZIF-8 membrane were explored to get the best performance. In addition, influence of conditions such as sweep speed and pH of the test solution on the electrochemical response signal of AA were also studied. Under the best conditions, the linear range of AA detection by this sensor is from 10 μmol L-1 to 2500 μmol L-1, and the detection limit is 5.2 μmol L-1 based on S/N = 3. What's more, the modified electrode also has good anti-interference ability, reproducibility and stability, and has achieved satisfactory results in the detection for AA in real samples.We suggest using a new tool, Procrustes cross-validation, as an alternative to a regular cross-validation for short datasets where each sample is important and, therefore, cannot be removed in line with the conventional leave-one-out cross-validation procedure. The advantages of the new approach are demonstrated using two real-world examples the first one contains discrete variables (chemical profiles). The second one is based on continuous data (spectra). The method is implemented in R and Matlab as a small procedure that any analyst can easily use.We developed a new transparent polymer optode based on polymethacrylate with Zr(IV) and alizarin red complex immobilized into it for digital colorimetric and solid-phase spectrophotometric determination of fluoride anions. The matrix changes its colour from purple to yellow after it contacts fluoride anion. We developed a processing algorithm for coloured images which helps calculate mean value for the RGB colour-coordinate system in a selected optode image and translates it into a fluoride concentration value. The analytical signal of the suggested method has a linearity range of 0.1-30 mg⋅L-1 with the detection limit 0.03 mg⋅L-1. Compared to other methods, the modified polymethacrylate matrix is actually a ready-to-use colorimetric system offering rapid results for drinking water quality control.In this study, we developed a fully integrated protein absolute quantification platform for simultaneous analysis of multiple tumor markers in human plasma, by which multiple target proteins (alpha-fetoprotein, prostate-specific antigen, carcino-embryonic antigen and mucin-1) were firstly enriched by aptamers immobilized capillary column using graphene oxide modified polymer microsphere as the separation matrix, and then the eluted target proteins were online denatured, reduced, desalted and digested by our developed fully automated sample treatment device (FAST), finally the resulting peptides were analyzed by parallel reaction monitoring (PRM) on LTQ-orbitrap velos mass spectrometry. Compared to traditional ELISA assay, the platform exhibited significant advantages such as short analysis time, low limit of detection, and ease of automation. Furthermore, our developed platform was also applied in the absolute quantification of tumor markers from clinical human plasma samples, and the results were comparable to those obtained by clinical immunoassay. All the results demonstrated that such a platform could provide a promising tool for achieving high sensitivity, high accuracy, and high throughput detection of disease related protein markers in the routine physical examination and clinical disease diagnosis.Temperature changes in cells are generally accompanied by physiological processes. Cellular temperature measurements can provide important information to fully understand cellular mechanisms. However, temperature measurements with conventional methods, such as fluorescent polymeric thermometers and thermocouples, have limitations of low sensitivity or cell state disturbance. We developed a microfluidic chip integrating a high-precision platinum (Pt) thermo-sensor that can culture cells and monitor the cellular temperature in situ. During detection, a constant temperature system with a stability of 0.015 °C was applied. The temperature coefficient of resistance of the Pt thermo-sensor was 2090 ppm/°C, giving a temperature resolution of the sensor of less than 0.008 °C. This microchip showed a good linear correlation between the temperature and resistance of the Pt sensor at 20-40 °C (R2 = 0.999). Lung and liver cancer cells on the microchip grew normally and continuously. The maximum temperature fluctuation of H1975 (0.