Recent advances in analytical chemistry--a material approach

Unveiling the multifaceted antiproliferative efficacy of Cichorium endivia root extract by dual modulation of apoptotic and inflammatory genes, inducing cell cycle arrest, and targeting COX-2

Chicory (Cichorium endivia L. divaricatum) is a renowned medicinal plant traditionally used for various ailments, yet the pharmacological potential of its roots, particularly in terms of antitumor activity, remains elusive. In the present study, we explore, for the first time, the metabolomic profile of ethanolic extract from Cichorium endivia roots (CIR) and further unveil its antiproliferative potential. The untargeted phytochemical analysis UPLC/T-TOF-MS/MS identified 131 metabolites in the CIR extract, covering acids, amino acids, flavonoids, alkaloids, nucleotides, and carbohydrates. The antiproliferative activity of the CIR extract was tested in 14 cancer cell lines, revealing significant cytotoxicity (IC50: 2.85-29.15 μg mL-1) and a high selectivity index. Among the cells examined, the CIR extract recorded the most potent antiproliferative activity and selectivity toward HepG2 and Panc-1 cells, with an IC50 of 2.85 μg mL-1 and 3.86 μg mL-1, respectively, and SI > 10. Insights into the mode of action of the antiproliferative activity revealed that CIR extract induces cell arrest in the S phase while diminishing cell distribution in the G0/G1 and G2/M phases in HepG-2 and Panc-1 cells. Flow cytometric and RT-PCR analysis revealed that the CIR extract significantly triggers apoptosis and modulates the expression of pro-apoptotic and anti-apoptotic genes. Furthermore, the CIR extract exhibited a pronounced anti-inflammatory activity, as evidenced by down-regulating key cytokines in LPS-induced RAW 264.7 cells and selectively inhibiting the COX-2 enzyme. Finally, the CIR extract showed a robust total antioxidant capacity, together with potent free radicals and metal scavenging properties, highlighting its role in alleviating oxidative stress. Taken together, this study highlights the multifaceted therapeutic potential of CIR extract as a natural-based antitumor supplement.

On detour index of cycloparaphenylene and polyphenylene molecular structures

Cycloparaphenylene is a particle that comprises a few benzene rings associated with covalent bonds in the para positions to frame a ring-like structure. Similarly, poly (para-phenylenes) are macromolecules that include benzenoid compounds straightforwardly joined to each other by C-C bonds. Because of their remarkable architectural highlights, these structures have fascinated attention from numerous vantage focuses. Descriptors are among the most fundamental segments of prescient quantitative structure-activity and property relationship (QSAR/QSPR) demonstrating examination. They encode chemical data of particles as quantitative numbers, which are utilized to create a mathematical correlation. The nature of a predictive model relies upon great demonstrating insights, yet additionally on the extraction of compound highlights. To a great extent, Molecular topology has exhibited its adequacy in portraying sub-atomic structures and anticipating their properties. It follows a two-dimensional methodology, just thinking about the interior plan, including molecules. Explicit subsets speak the design of every atom of topological descriptors. When all around picked, these descriptors give a unique method of describing an atomic system that can represent the most significant highlights of the molecular structure. Detour index is one such topological descriptor with much application in chemistry, especially in QSAR/QSPR studies. This article presents an exact analytical expression for the detour index of cycloparaphenylene and poly (para-phenylene).

Nanomaterial based electrochemical sensing of the biomarker serotonin: a comprehensive review

This review (with 131 references) summarizes the progress made in the past years in the field of nanomaterial based sensing of serotonin (5-HT). An introduction summarizes the significant role of 5-HT as a biomarker for several major diseases, methods for its determination and the various kinds of nanomaterials for use in electrochemical sensing process relies principally on a precise choice of electrodes. The next main section covers nanomaterial based methods for sensing 5-HT, with subsections on electrodes modified with carbon nanotubes, graphene related materials, gold nanomaterials, and by other nanomaterials. A concluding section discusses future perspectives and current challenges of 5-HT determination. Graphical abstract Conceptual design of electrochemical sensing process of the biomarker serotonin by using nanomaterials and the role of 5-HTas biomarker in the body from preclinical to clincal.

Nanoparticle-Assisted Metabolomics

Understanding and harnessing the interactions between nanoparticles and biological molecules is at the forefront of applications of nanotechnology to modern biology. Metabolomics has emerged as a prominent player in systems biology as a complement to genomics, transcriptomics and proteomics. Its focus is the systematic study of metabolite identities and concentration changes in living systems. Despite significant progress over the recent past, important challenges in metabolomics remain, such as the deconvolution of the spectra of complex mixtures with strong overlaps, the sensitive detection of metabolites at low abundance, unambiguous identification of known metabolites, structure determination of unknown metabolites and standardized sample preparation for quantitative comparisons. Recent research has demonstrated that some of these challenges can be substantially alleviated with the help of nanoscience. Nanoparticles in particular have found applications in various areas of bioanalytical chemistry and metabolomics. Their chemical surface properties and increased surface-to-volume ratio endows them with a broad range of binding affinities to biomacromolecules and metabolites. The specific interactions of nanoparticles with metabolites or biomacromolecules help, for example, simplify metabolomics spectra, improve the ionization efficiency for mass spectrometry or reveal relationships between spectral signals that belong to the same molecule. Lessons learned from nanoparticle-assisted metabolomics may also benefit other emerging areas, such as nanotoxicity and nanopharmaceutics.

Novel chiral ionic liquids stationary phases for the enantiomer separation of chiral acid by high-performance liquid chromatography

Novel chiral ionic liquid stationary phases based on chiral imidazolium were prepared. The ionic liquid chiral selector was synthesized by ring opening of cyclohexene oxide with imidazole or 5,6-dimethylbenzimidazole, and then chemically modified by different substitute groups. Chiral stationary phases were prepared by bonding to the surface of silica sphere through thioene "click" reaction. Their enantioselective separations of chiral acids were evaluated by high-performance liquid chromatography. The retention of acid sample was related to the counterion concentration and showed a typical ion exchange process. The chiral separation abilities of chiral stationary phases were greatly influenced by the substituent group on the chiral selector as well as the mobile phase, which indicated that, besides ion exchange, other interactions such as steric hindrance, π-π interaction, and hydrogen bonding are important for the enantioselectivity. In this report, the influence of bulk solvent components, the effects of varying concentration, and the type of the counterion as well as the proportion of acid and basic additives were investigated in detail.

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, reviews, edited volumes and monographs from this period are included, along with recently identified uncited materials from prior to 2004, which were omitted in the first instalment of this series covering the years 1930-2003. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by sections describing fundamental aspects of molecular imprinting including the development of novel polymer formats. Thereafter, literature describing efforts to apply these polymeric materials to a range of application areas is presented. Current trends and areas of rapid development are discussed.

Proteomic analysis of cellular response induced by multi-walled carbon nanotubes exposure in A549 cells

The wide application of multi-walled carbon nanotubes (MWCNT) has raised serious concerns about their safety on human health and the environment. However, the potential harmful effects of MWCNT remain unclear and contradictory. To clarify the potentially toxic effects of MWCNT and to elucidate the associated underlying mechanisms, the effects of MWCNT on human lung adenocarcinoma A549 cells were examined at both the cellular and the protein level. Cytotoxicity and genotoxicity were examined, followed by a proteomic analysis (2-DE coupled with LC-MS/MS) of the cellular response to MWCNT. Our results demonstrate that MWCNT induces cytotoxicity in A549 cells only at relatively high concentrations and longer exposure time. Within a relatively low dosage range (30 µg/ml) and short time period (24 h), MWCNT treatment does not induce significant cytotoxicity, cell cycle changes, apoptosis, or DNA damage. However, at these low doses and times, MWCNT treatment causes significant changes in protein expression. A total of 106 proteins show altered expression at various time points and dosages, and of these, 52 proteins were further identified by MS. Identified proteins are involved in several cellular processes including proliferation, stress, and cellular skeleton organization. In particular, MWCNT treatment causes increases in actin expression. This increase has the potential to contribute to increased migration capacity and may be mediated by reactive oxygen species (ROS).

Use of nanomaterials in capillary and microchip electrophoresis

This review gives an overview of different separation strategies with nanomaterials and their use in capillary electrophoresis (CE) and capillary electrochromatography, as well as in microchip electrophoresis, including metal and metal oxide nanoparticles, carbon nanotubes, fullerene and polymer nanoparticles, as well as silica nanoparticles. The paper highlights the new developments and innovative applications of nanoparticles as pseudostationary phases or immobilized on the capillary surface for CE separation. The separation and characterization of target nanoparticles with different sizes by CE are reviewed likewise.

Nanomaterials for ultrasensitive protein detection

The advances of nanomaterials have provided exciting technologies and novel materials for protein detection, based on the unique properties associated with nanoscale phenomena such as plasmon resonance, catalysis and energy transfer. This article reviews a series of nanomaterials including nanoparticles, nanofibers, nanowires, and nanosheets, and evaluates their performances in the application for protein detection, focusing on approaches that realize ultrasensitive detection. Many of these nanomaterials were used to analyze clinically relevant protein biomarkers. Their detection in the picomolar, femtomolar or even zeptomolar regime has been realized, sometimes even with naked-eye readout. We summarize the detection methods and results according to materials and targets, review the current challenges, and discuss the solution in the context of technological integration such as combining nanomaterials with microfluidics, and classical analytical technologies.

Recent applications of carbon-based nanomaterials in analytical chemistry: critical review

The objective of this review is to provide a broad overview of the advantages and limitations of carbon-based nanomaterials with respect to analytical chemistry. Aiming to illustrate the impact of nanomaterials on the development of novel analytical applications, developments reported in the 2005-2010 period have been included and divided into sample preparation, separation, and detection. Within each section, fullerenes, carbon nanotubes, graphene, and composite materials will be addressed specifically. Although only briefly discussed, included is a section highlighting nanomaterials with interesting catalytic properties that can be used in the design of future devices for analytical chemistry.

The optimization of the electrochemical preparation of Pedot-Prussian blue hybrid electrode material and application in electrochemical sensors

The electrochemical preparation, characterization and analytical applications of a hybrid material consisting of poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer and Prussian Blue (PB; iron(III) hexacyanoferrate(II)) are presented. The hybrid material was prepared by a two-steps method. In a first step, the organic conducting polymer coating was deposited onto platinum electrode surface from an aqueous solution containing the monomer and ferricyanide ions. In the second step, the resulted modified electrode Pt|PEDOT- FeCN was immersed in an aqueous solution containing Fe3+ ions and the electrode potential was cycled between 0.6 and –0.4 V. The in situ formation of PB inside the PEDOT matrix has been demonstrated using cyclic voltammetry and electrochemical quartz crystal microbalance. The hybrid material maintains the electrochemical features of each component, i.e. organic and inorganic components. The inorganic component showed electrochemical activity only for the Prussian blue/Everitt’s salt redox system. The hybrid material displayed electrocatalytic activity towards dopamine oxidation in the presence of a large excess of ascorbic acid.

Nanotechnology-based electrochemical sensors for biomonitoring chemical exposures

The coupling of dosimetry measurements and modeling represents a promising strategy for deciphering the relationship between chemical exposure and disease outcome. To support the development and implementation of biological monitoring programs, quantitative technologies for measuring xenobiotic exposure are needed. The development of portable nanotechnology-based electrochemical (EC) sensors has the potential to meet the needs for low cost, rapid, high-throughput, and ultrasensitive detectors for biomonitoring an array of chemical markers. Highly selective EC sensors capable of pM sensitivity, high-throughput and low sample requirements (<50 microl) are discussed. These portable analytical systems have many advantages over currently available technologies, thus potentially representing the next generation of biomonitoring analyzers. This paper highlights research focused on the development of field-deployable analytical instruments based on EC detection. Background information and a general overview of EC detection methods and integrated use of nanomaterials in the development of these sensors are provided. New developments in EC sensors using various types of screen-printed electrodes, integrated nanomaterials, and immunoassays are presented. Recent applications of EC sensors for assessing exposure to pesticides or detecting biomarkers of disease are highlighted to demonstrate the ability to monitor chemical metabolites, enzyme activity, or protein biomarkers of disease. In addition, future considerations and opportunities for advancing the use of EC platforms for dosimetric studies are discussed.