Application Of CE Research Articles

Effect of Cerium (Ce) on the Redox States of Ascorbate and Glutathione through Ascorbate-glutathione Cycle in the Roots of Maize Seedlings under Salt Stress

This study investigated the effect of cerium (Ce) on the ascorbate-glutathione (AsA-GSH) cycle in the roots of maize seedlings under salt stress. The results showed that salt stress significantly increased the activities of ascorbate peroxidase (APX) and monodehydroascorbate reductase (MDHAR), malondialdehyde (MDA) content and electrolyte leakage (EL) in the roots of maize seedlings, compared to the control. However, salt stress significantly decreased plant height, dry weight of root and shoot, the activities of glutathione reductase (GR) and dehydroascorbate reductase (DHAR), and the ratios of AsA/DHA and GSH/GSSG in the roots of maize seedlings, compared to the control. Pretreatment with cerium nitrate (Ce(NO3)3) significantly increased plant height, dry weight of root and shoot, the activities of above four enzymes, and the ratios of AsA/DHA and GSH/GSSG under salt stress, compared to salt stress alone. Pretreatment with Ce(NO3)3 significantly decreased MDA content and EL induced by salt stress, compared to salt stress alone. Meanwhile, application of Ce(NO3)3 to the control also significantly increased plant height, dry weight of root and shoot, the activities of above four enzymes and the ratios of AsA/DHA and GSH/GSSG, and decreased MDA content and EL, compared with control. Our results suggested that Ce(NO3)3 alleviated salt stress-induced oxidative damage by improving AsA-GSH cycle in maize roots.

Recent trends in capillary electrophoresis for complex samples analysis: A review.

CE has been a continuously evolving analytical methodology since its first introduction in the 1980s of the last century. The development of new CE separation procedures, the coupling of these systems to more sensitive and versatile detection systems, and the advances in miniaturization technology have allowed the application of CE to the resolution of new and complex analytical problems, overcoming the traditional disadvantages associated with this method. In the present work, different recent trends in CE and their application to the determination of high complexity samples (as biological fluids, individual cells, etc.) will be reviewed: capillary modification by different types of coatings, microfluidic CE, and online microextraction CE. The main advantages and disadvantages of the different proposed approaches will be discussed with examples of most recent applications.

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics.

This review work presents and discusses the main applications of capillary electromigration methods in food analysis and Foodomics. Papers that were published during the period February 2015-February 2017 are included following the previous review by Acunha etal. (Electrophoresis 2016, 37, 111-141). The paper shows the large variety of food related molecules that have been analyzed by CE including amino acids, biogenic amines, carbohydrates, chiral compounds, contaminants, DNAs, food additives, heterocyclic amines, lipids, peptides, pesticides, phenols, pigments, polyphenols, proteins, residues, toxins, vitamins, small organic and inorganic compounds, as well as other minor compounds. This work describes the last results on food quality and safety, nutritional value, storage, bioactivity, as well as uses of CE for monitoring food interactions and food processing including recent microchips developments and new applications of CE in Foodomics.

Screening bioactive compounds from natural product and its preparations using capillary electrophoresis.

Bioactive ingredients of natural products can protect human body from harm, as well as prevent and treat disease. Screening bioactive compounds from natural products is attracting particular attention. It is a great challenge to separate and detect the active compounds from complex matrix natural products. CE plays a vital role in screening active compounds because of its unique features such as high-efficiency separation, short-analysis time, minimal sample consumption, and ease to realize automatization etc. Additionally, CE has been developed various modes owing to its abundant advantages in analysis and separation of compounds. The purpose of this work is to review previous developments and applications of CE in screening bioactive compounds derived from natural products from 2007 to 2017. This review does not only summarize the traditional methods of detecting active ingredients but also briefly introduces some novel assays. The trends in the application of CE in active compounds screening are addressed in the article.

Addition of cerium and yttrium to ferritic steel weld metal to improve hydrogen trapping efficiency

The applicability of Ce and Y as promising candidate elements to form irreversible traps in weld metal was investigated by thermal desorption spectroscopy (TDS) with gas chromatography (GC). The precise nature of the precipitate particles newly formed in the weld metal by the addition of Ce and Y to a certain alloy system was characterized. Moreover, the hydrogen trapping efficiency expressed as the reduction of the diffusible hydrogen in the weld metal was analyzed. The results showed that the addition of Ce and/or Y to this alloy system led to the formation of a mixed type of (Ce,Ti)-based oxide, (Y,Ni)-based carbide, or (Ce,Y,Ti)-based oxide particles. Because of the high activation energy of the mixed type of particles (≥ 150 kJ/mol), the trapping efficiency for hydrogen was considered to be sufficiently high to effectively reduce the diffusible hydrogen content.

CE-MS for metabolomics: Developments and applications in the period 2014-2016.

CE–MS can be considered a useful analytical technique for the global profiling of (highly) polar and charged metabolites in various samples. Over the past few years, significant advancements have been made in CE–MS approaches for metabolomics studies. In this paper, which is a follow‐up of a previous review paper covering the years 2012–2014 (Electrophoresis 2015, 36, 212–224), recent CE–MS strategies developed for metabolomics covering the literature from July 2014 to June 2016 are outlined. Attention will be paid to new CE–MS approaches for the profiling of anionic metabolites and the potential of SPE coupled to CE–MS is also demonstrated. Representative examples illustrate the applicability of CE–MS in the fields of biomedical, clinical, microbial, plant, and food metabolomics. A complete overview of recent CE–MS‐based metabolomics studies is given in a table, which provides information on sample type and pretreatment, capillary coatings, and MS detection mode. Finally, general conclusions and perspectives are given.

Capillary electrophoresis hyphenated with UV‐native‐laser induced fluorescence detection (CE/UV‐native‐LIF)

Native laser-induced fluorescence using UV lasers associated to CE offers now a large related literature, for now 30 years. The main works have been performed using very expensive Ar-ion lasers emitting at 257 and 275 nm. They are not affordable for routine analyses, but have numerous applications such as protein, catecholamine, and indolamine analysis. Some other lasers such as HeCd 325 nm have been used but only for few applications. Diode lasers, emitting at 266 nm, cheaper, are extensively used for the same topics, even if the obtained sensitivity is lower than the one observed using the costly UV-Ar-ion lasers. This review presents various CE or microchips applications and different UV lasers used for the excitation of native fluorescence. We showed that CE/Native UV laser induced fluorescence detection is very sensitive for detection as well as small aromatic biomolecules than proteins containing Trp and Tyr amino acids. Moreover, it is a simple way to analyze biomolecules without derivatization.

Selective Ce(III) ion-imprinted polymer grafted on Fe3O4 nanoparticles supported by SBA-15 mesopores microreactor via surface-initiated RAFT polymerization

Ce(III) ion-imprinted polymer (Ce(III)-IIP) grafted on Fe3O4 nanoparticles supported by SBA-15 mesopores microreactor was successfully synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization for selective removal of Ce(III) from aqueous solution. The characterization results suggest that the surface ion-imprinted polymer (IIP) synthesized by RAFT is a thin layer. Adsorption isotherm experiments indicated that Redlich-Peterson isotherm model best fitted the experimental data and the adsorption capacity of IIP was obviously higher than that of non-imprinted polymers (NIP) at the same conditions. The kinetics of adsorption followed the Thomas model. Moreover, competitive adsorption studies illustrated that Ce(III)-IIP offers the advantages of selectivity towards Ce(III) compared with NIP even in the presence of other metal ions. All above results indicated the potential application of Ce(III)-IIP for selective removal of Ce(III) from aqueous solution.

Spectroscopic ellipsometry as a complementary tool to characterize coatings on PDMS for CE applications.

This paper describes the use of spectroscopic ellipsometry to investigate the adsorption process of model polyelectrolytes (PDDAC and PSS) to thin-films of PDMS. A description of the information collected by ellipsometry as well as complementary information obtained by atomic force microscopy and contact angle measurements is discussed. Upon identification of the driving forces and optimum experimental conditions required for the adsorption, multilayer constructs were fabricated (ranging from 1 to 20 nm in thickness) and used to evaluate their effect on the separation of phenolic compounds by capillary electrophoresis. According to the presented results, polyelectrolyte layers of approximately 10 nm thick provided the best conditions for the separation of the selected phenolic compounds.

Database Development for the Urgent Department of Hospital based on Tagged Entity Storage Following the IoT Concept

Abstract: This paper deals with creating the database for the urgent department of the Faculty Hospital of Ostrava. The database is based on the concept of the Internet Of Things. Selected elements are saved to the database using low-cost identifiers that also creates records of use. It is described analysis of the urgent environment and the working process and working environment of the emergency department. It was also necessary to make analysis of each part which will be entered into the process of making electronic registration and medical records as RFID technology, passive tags, WiFi network, etc. It was developed medical database where are stored medical registration and records thanks RFID technology. For the database MySQL database server with client MySQL Workbench 5.2.42.CE application was used. In this paper is also described its implementation and testing's involved.

Recent applications of CE- and HPLC-MS in the analysis of human fluids.

The present review intends to cover the literature on the use of CE-/LC-MS for the analysis of human fluids, from 2010 until present. It has been planned to provide an overview of the most recent practical applications of these techniques to less extensively used human body fluids, including, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate, tear fluid, breast fluid, amniotic fluid, and cerumen. Potential pitfalls related to fluid collection and sample preparation, with particular attention to sample clean-up procedures, and methods of analysis, from the research laboratory to a clinical setting will also be addressed. While being apparent that proteomics/metabolomics represent the most prominent approaches for global identification/quantification of putative biomarkers for a variety of human diseases, evidence is also provided of the suitability of these sophisticated techniques for the detection of heterogeneous components carried by these fluids.

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics.

This review work presents and discusses the main applications of capillary electromigration methods in food analysis and Foodomics. Papers that were published during the period February 2013-February 2015 are included following the previous review by Garcia-Cañas et al. (Electrophoresis, 2014, 35, 147-169). Analysis by CE of a large variety of food-related molecules with different chemical properties, including amino acids, hazardous amines, peptides, proteins, phenols, polyphenols, lipids, carbohydrates, DNAs, vitamins, toxins, contaminants, pesticides, residues, food additives, as well as small organic and inorganic compounds. This work includes recent results on food quality and safety, nutritional value, storage, bioactivity, as well as applications of CE for monitoring food processing. The use, among other CE developments, of microchips, CE-MS, and chiral CE in food analysis and Foodomics is also discussed.

Capillary electrophoresis for fast detection of heterogeneous population in colistin-resistant Gram-negative bacteria.

It has been shown that diverse strains of bacteria can be separated according to their characteristic surface properties by means of CE. We employed here this analytical technique to the study of colistin-resistance in Gram-negative bacteria, which involves the selection of mutants with modified outer membrane composition resulting in changes of surface cell properties. In the same way as with molecular entities, we performed firstly the validation of an ITP-based CE method for three common pathogenic Gram-negative bacteria namely Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Secondly, we compared the electrophoretic profiles of bacterial samples from a colistin-susceptible clinical isolate of K. pneumoniae and from the corresponding colistin-resistant derivative. By a simple CE run taking a few minutes, the coexistence of several bacterial subpopulations in the colistin-resistant derivative was clearly evidenced. This work encourages further research that would allow applications of CE in clinical laboratory for a daily monitoring of bacterial population in cared patients when "last-chance" colistin treatment is initiated against multidrug-resistant bacteria.

Identification of poultry species using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and capillary electrophoresis-single strand conformation polymorphism (CE-SSCP) methods

In the last decades, animal species identification became more important to prevent food adulteration. Here, we demonstrate the identification of seven poultry species, chicken, guinea fowl, pheasant, turkey, goose, duck and muscovy duck, through the use of the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and capillary electrophoresis-single strand conformation polymorphism (CE-SSCP) methods. DNA were isolated from poultry meat and meat products and were amplified with universal primers, designed for the mitochondrial 12S rRNA. Species-specific patterns and the reliable detection limit were identified as 0.5% for PCR and CE applications. Analyses of commercially available poultry products revealed fraud, as 6 of 36 contained undeclared species. The above-mentioned techniques are sensitive, reproducible and reliable for poultry species identification from foodstuffs.

Comparison of detection techniques for capillary electrophoresis analysis of gold nanoparticles.

As metallic nanoparticles are growing in importance as analytes in CE, increases an interest in appropriate detection methods for their quantification in various samples. For gold nanoparticles (AuNPs), the most common UV detection poses intricacy of inadequate sensitivity that hinders the applicability of CE. With the objective of resolving this challenge, UV detection was compared with C(4) D and ICP-MS as alternative modes of detection for AuNPs. A C(4) D detector, applied under pressure-driven conditions, exhibited better sensitivity than a UV detector. However, C(4) D turned to be unsatisfactory to differentiate the signal of AuNPs at common CE conditions despite varying the nature of BGE and detection conditions. Due to intrinsic sensitivity and low background levels typical to Au, ICP-MS greatly surpasses UV detection. After optimization trials, CE-ICP-MS gained the LOD of AuNPs as low as 2 × 10(-15) M, as well as an excellent performance in terms of signal stability and linearity. Also importantly, the optimized BGE appears to be well matched to explore the behavior of AuNPs in biologically relevant systems. This was demonstrated by probing the interaction between AuNPs and the main blood-transporting protein, HSA.

Kabachnik-Fields and Prins- Ritter Synthesis: Application of Ce(III) Supported on a Weakly Acidic Cation-exchanger Resin in Comparative Study

We described results of comparative studies of the application of Ce(III) cation supported on macroporous weakly acidic polyacrylate resin as catalyst in two model three-component domino syntheses, i.e. Kabachnik-Fields domino synthesis of alpha-aminophosphonates, and Prins-Ritter domino synthesis of 4-amidotetrahydropyrane derivatives, respectively. It was discovered that cation Ce(III) supported on a weak acid macroporous cation-exchanger shown in the studied reactions at least the same or better catalytic activity as salt CeCl3.7H2O, eventually doped by NaI. Further, we found that reactivity of the low reactive 4-methoxybenzaldehyde as carbonyl compounds in the presence of Ce(III) catalyst increases, while the reactivity of the highly reactive 4-nitrobenzaldehyde in this case strongly decreases due to its low coordination with the catalyst. Finally, the presented synthetic protocols using cerium(III) supported on low-cost industrial resin further increases green impact of studied domino syntheses of alpha-aminophosphonates, and 4-amidotetrahydropyrane derivatives.

Contactless conductivity detection for analytical techniques—Developments from 2012 to 2014

The review covers the progress of capacitively coupled contactless conductivity detection over the 2 years leading up to mid-2014. During this period many new applications for conventional CE as well as for microchip separation devices have been reported; prominent areas have been clinical, pharmaceutical, forensic, and food analyses. Further progress has been made in the development of field portable instrumentation based on CE with contactless conductivity detection. Several reports concern the combination with sample pretreatment techniques, in particular electrodriven extractions. Accounts of arrays of contactless conductivity detectors have appeared, which have been created for quite different tasks requiring spatially resolved information. The trend of the use of contactless conductivity measurements for applications other than CE has continued.

Application of CE-MS to a metabonomics study of human urine from cigarette smokers and non-smokers.

Novel biomarkers of exposure and early adverse effects are needed for comparative studies of combustible and non-combustible tobacco products for regulatory authority evaluation. Metabolic biomarkers reflect both gene and environmental effects. CE-MS has been applied to human urine samples from non-smokers and smokers of cigarettes at two tar levels. Validated chemometric models were able to separate smokers from non-smokers, with discrimination mainly based on the presence of nicotine metabolites. With these removed, it still proved possible to discriminate smokers from non-smokers with models now based on endogenous metabolites. The biochemical relevance of these biomarkers is discussed. This proof-of-principle metabonomics study illustrates the potential of CE-MS to discover novel biomarkers in urine from tobacco users.

Synthesis, physical properties and antibacterial activity of Ce doped CuO: a novel nanomaterial

CuO nanostructures doped with Ce at different concentration levels have been synthesized via a simple co-precipitation technique. The prepared samples have been characterized by x-ray diffraction, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and UV–visible absorption spectroscopy. Structural studies exhibit the presence of a monoclinic structure of CuO for undoped and Ce doped samples without any additional impurity phases. SEM images have revealed the rod-like morphology with an average diameter of 30 nm for undoped CuO. FTIR results of undoped and Ce doped CuO nanostructures have further confirmed the formation of monoclinic CuO. The optical band gap calculated from the Tauc relation has been observed to be 2.48 eV for undoped CuO nanostructures, which is found to decrease down to 2.2 eV with the increase in the Ce doping level. This tuning in the optical band gap may be attributed to the merging of the impurity band with the conduction band of CuO. The Ce doping induced effects on the antibacterial activity of the CuO nanostructures have been examined by recording the growth curves of bacteria in the presence of prepared nanostructures. It has been observed that S. aureus bacterium may be completely eradicated by the application of Ce doped CuO nanostructures. Finally, the cytotoxicity analysis has shown that the synthesized undoped and Ce doped CuO nanostructures are biocompatible and non-toxic towards the human cell line SH-SY5Y cells.

Surface modification by grafting of poly(SBMA-co-AEMA)-g-PDA coating and its application in CE

In this paper, a novel copolymer consisting of sulfobetaine methacrylate (SBMA) and 2-aminoethyl methacrylate (AEMA) named as poly(SBMA-co-AEMA) was synthesized by conventional free-radical polymerization, the poly(SBMA-co-AEMA) zwitterionic copolymer was immobilized onto glass slides surface through polydopamine (PDA)-anchored coating and formed poly(SBMA-co-AEMA)-g-PDA coating. The defined copolymer was characterized by nuclear magnetic resonance hydrogen spectroscopy (1H NMR) and gel permeation chromatography. The surface morphology, thickness, and chemical component of poly(SBMA-co-AEMA)-g-PDA coating were studied by atom force microscope, ellipsometry, and X-ray photoelectron spectroscopy, respectively. The hydrophilicity and stability of these coatings were investigated by static water contact angles. And finally, the poly(SBMA-co-AEMA)-g-PDA coating was successfully applied into capillary inner surface for suppression electro-osmotic flow and protein separation by capillary electrophoresis.