Generally, the ECL intensity of electrochemiluminescence immunosensor changes linearly with the logarithm of CA 72-4 concentration in the range from 5 × 10-5 to 5 × 102 U mL-1 and the detection limit of 1.48 × 10-5 U mL-1 (S/N = 3). Furthermore, the experiment results show that the constructed CA 72-4 immunosensor has excellent reproducibility and can be used for the sensitive detection of CA 72-4 in human serum. The approach opens up the new way for clinical bioassays.Contamination of water with nitrate ions is a significant problem that affects many areas of the world. For this reason, European legislation has set the maximum permissible concentration of nitrates in drinking water at 44 mg/L. Thus, it is clear that a continuous monitoring of nitrate ions is of high technological interest but it must be rapid, easy to perform and directly performable in situ. In this work we have developed a nanostructured sensor based on array of copper nanowires obtained with the simple method of galvanic deposition. The nanostructured sensors have a very short response time with a detection limit less than 10 μM. Different interfering species were tested finding a negligible effect except for the chloride ions. However, this problem has been solved by removing chloride ions from the water through a simple precipitation of chloride compounds with low solubility. Nanostructured sensors were also used to analyze real water samples (rain, river and drinking water). In the case of drinking water, we have measured a concentration of nitrate ions very close to the that measured by conventional laboratory techniques.The field of medical diagnostics has endeavored to explore single species of biomolecules for sensitive and informative disease diagnostic applications. Here, Raman hyperspectroscopy is used to analyze red blood cells for identifying Celiac disease (CD). CD is a common autoimmune disorder which affects approximately 1% of the population. The ingestion of gluten by an individual with CD will result in the body initiating a violent immune response which causes severe damage to the small intestine. If the disease goes undiagnosed, substantial long-term health complications ranging in severity can arise. It is thus crucial to identify the disease as early on as possible to prevent additional problems from manifesting. However, current methods for detecting CD are expensive, invasive, and laborious. It was therefore the goal of this study to develop a better method for diagnosing CD which is noninvasive, inexpensive, accurate and definitive. Raman hyperspectroscopy was used to investigate individual red blood cells from donors with CD and from healthy controls who follow a gluten-free diet. Partial least squares discriminant analysis (PLS-DA) was used to evaluate the collected Raman spectral data for diagnostic purposes. Receiver operating characteristic (ROC) curve analysis was applied to evaluate the performance of the PLS-DA prediction algorithm, resulting in 100% successful external validation of the developed method at the donor level. Raman hyperspectroscopy in combination with chemometric analysis is shown herein to successfully evaluate red blood cells for the accurate detection of CD in a noninvasive, simple, and cost-effective manner.Linezolid and beta-lactams are anti-infective drugs frequently used in intensive care unit patients. Critical illness could induce alterations of pharmacokinetic parameters due to changes in the distribution, the metabolism and the elimination process. Therapeutic drug monitoring (TDM) is therefore recommended to prevent mainly under-dosing of beta-lactams or hematological and neurological toxicities of linezolid. In Multi-or Extensively-Drugs Resistant-Tuberculosis Bacteria, the regimen could include linezolid with meropenem and amoxicillin/clavulanate justifying the development of a method allowing their simultaneous quantification. The aim of this work was to develop an in-house ultra-performance liquid chromatography method with UV detection (UHPLC-PDA) allowing the simultaneous determination of 8 beta-lactams (amoxicillin, aztreonam, cefepime, ceftazidime, ceftriaxone, cefuroxime, meropenem and piperacillin) and linezolid and to cross-validate the linezolid quantification with a new commercial immunoassa50 mg/L for linezolid and 1-200 mg/L for other beta-lactams) with an intermediate precision and a relative bias below 7.6 and 7.7%, respectively. The analytical range of the immunoassay was narrower, from 0.85 to 18.5 mg/L. The precision and relative bias were lower than 8.1% and 4.2%, respectively. Results obtained on clinical samples showed an acceptable difference between methods with a mean bias of -1.8% [95% confidence interval -5.2% – 1.6%]. To conclude, both methods showed acceptable performance to perform TDM of linezolid considering the therapeutic through target of 2-8 mg/L. The choice of the method should be made according to the degree of emergency of the response required and the field of application justifying or not the simultaneous quantification of beta-lactams and linezolid.Simple, sensitive and rapid detection of circulating tumor cells (CTCs) is of great importance for early diagnosis and therapy of cancers. Overexpression of sugar units on cell surface is related to the phenotypes of many cancers. Based on the boronate ester interaction, we reported the electrochemical and colorimetric detection of CTCs with high simplicity and sensitivity. Specifically, ferroceneboronic acid (FcBA) can be measured by differential pulse voltammetry and 4-mercaptophenylboronic acid (MPBA) can induce the aggregation and color change of gold nanoparticles (AuNPs). CTCs captured by the aptamer-modified magnetic beads (Apt-MBs) can sequestrate FcBA or MPBA molecules by the formation of boronate ester bonds, thus leading to the decrease in the electrochemical signal of FcBA or preventing the MPBA-triggered aggregation of AuNPs. Due to the overexpression of sugar groups on the surface of CTCs, the amplification-free methods exhibited high sensitivity and obviated the use of additional antibody or aptamer for the recognition of captured cells. With MCF-7 cancer cell as the model, 50 cells can be readily determined by the electrochemical and colorimetric methods. The proposed strategy is valuable for probing of cell glycosylation and designing of novel sensing devices for detection of sugar-containing biological macromolecules and cells.Cyanide released from mostly industrial production is a highly toxic chemical. Its heavy industrial use and transportation increase the danger of human exposure. Since it can often lead to rapid death, selective, sensitive and on-site and rapid monitoring techniques for the detection of cyanide are essential. Therefore, we report an efficient cyanide probe based on thiazolium conjugated HBT-Br derivative. It has striking color change toward cyanide blue to yellow under daylight or colorless to cyan under UV-light. Interaction modes of the probe are based on ESIPT and ICT processes. It is selectively able to react free aqueous cyanide with detection limit of 1.79 μM, lower than physiologically lethal blood levels, >20 μM. Smartphone assisted and test kit applications are able to detect cyanide, qualitatively. Moreover, real samples such as tap or lake water and apricot seeds including cyanide are successfully determined through the present probe. Therefore, the designed probe displays excellent practical potential toward cyanide.A highly-enriched 233U reference material (>0.99987 n(233U)/n(U)) has been prepared and characterized for use as an isotope dilution mass spectrometry spike. An ion exchange separation was performed on 1 g of high purity 233U to further reduce trace amounts of contaminant Pu in the material. The purified 233U was then prepared as a master solution which was analyzed for molality of uranium by modified Davies and Gray titration. A portion of the master solution was quantitatively diluted and dispensed for reference material units. Selected units were analyzed for verification of uranium amount and to characterize uranium isotope amount ratios by multi-collector inductively couple plasma mass spectrometry. Modelling of spike-corrected isotopic data show that the new spike will enable simultaneous measurements of uranium amount and isotope amount ratios with resulting uncertainties that are substantially less sensitive to over spiking than widely used 233U certified reference materials.Determination of 135Cs concentration and 135Cs/137Cs atomic ratio is of great importance in characterization of radioactive waste from decommissioning of nuclear facilities. In this work, an effective analytical method was developed for simultaneously determination of 135Cs and 137Cs in different types of waste samples (steel, zirconium alloy, reactor coolant, ion exchange filter paper and spent ion exchange resin) by coupling AMP-PAN, AG MP-1M and AG 50 W-X8 chromatographic separation with ICP-MS/MS measurement. Decontamination factors of 7.0 × 106 for Co, 6.0 × 106 for Ba, 4.2 × 105 for Mo, 3.2 × 105 for Sn and 2.1 × 105 for Sb were achieved using the chemical separation procedure. The overall chemical yields of cesium were higher than 85%. A detection limit of 3.1 × 10-14 g/g for 135Cs was achieved for 0.2 g stainless steel sample or spent resin. The developed method was validated by analysis of standard reference materials (IAEA-375) and successfully applied for analysis of zirconium alloy, steel, ion exchange filter paper and spent ion exchange resin from nuclear power reactors. The obtained 135Cs can be used to evaluate the long-term environmental impact and provide useful information for waste disposal. The measured 135Cs/137Cs ratio in reactor coolant, as a characteristic information, might be useful for source identification and localization of leaked fuel element. The neutron flux of the leaked fuel element can be estimated based on the measured 135Cs/137Cs atomic ratios in the reactor coolant water. The developed method is simple and rapid (8 samples/day) for the determination of 135Cs concentrations and 135Cs/137Cs ratios in various waste samples from nuclear decommissioning.Since the rare earth elements (REEs) determination in waters is still not a routine procedure, different analytical protocols have been developed to deal with complexity and variability of sample matrices, problems caused by spectral and non-spectral interferences, insufficient instruments sensitivity, potential contamination and lack of certified reference materials. The aim of this work is to review the current measurement approaches given for REEs total concentrations in natural water samples, including surface and groundwaters as well as rain water and Antarctic ice. As inductively coupled plasma mass spectrometry (ICP-MS) has become the most widely employed technique for analysis of trace concentrations of REEs in aqueous samples it has been intended to present the common issues affecting the measurement results. Apart from a sample preparation step, various configurations of mass spectrometers and sample introduction systems, means of interferences elimination or correction, and calibration strategies used in analytical approaches for REEs analysis are discussed and compared.