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Biography
John Fenn
John Bennett Fenn (June 15, 1917 – December 10, 2010) was an American professor of analytical chemistry who was awarded a share of the Nobel Prize in Chemistry in 2002. Fenn shared half of the award with Koichi Tanaka for their work in mass spectrometry. The other half of the 2002 award went to Kurt Wüthrich. Fenn's contributions specifically related to the development of electrospray ioniza
  • 1.9K
  • 17 Nov 2022
Topic Review
Sample Preparation for Cosmetics Analysis
Traditional cosmetics sample preparation techniques involve liquid–liquid extraction (LLE) and solid–liquid extraction (SLE). In last years, modern sample extraction techniques are advancing towards fast sample processing, easy automatization, as well as a reduction in organic solvent volumes, in agreement with the green chemistry principles in two ways (i) the miniaturization of conventional procedures allowing a reduction of the solvents and reagents consumption and (ii) the development and application of sorbent- and liquid-based microextraction technologies to obtain a high analyte enrichment, avoiding or significantly reducing the use of organic solvents.
  • 1.9K
  • 24 Nov 2021
Topic Review
Noble Metal Nanoparticles in SERS
Surface-enhanced Raman spectroscopy (SERS) has become one of the most attractive analytical techniques due to its versatility and high sensitivity for a variety of analytes like dyes, food additives, pesticides, explosives, DNA, and other biomolecules at very low concentrations. Furthermore, SERS analysis possesses a broad range of properties: it is non-destructive, portable, easy to perform, highly sensitive, fast, cost-effective, and can be used when samples are present in water since the background signal is negligible. SERS substrates may consist of metallic nanoparticles, roughened metallic surfaces, or nanoengineered surfaces with metallic nanoparticles deposited on a solid support.  
  • 1.8K
  • 20 Dec 2021
Topic Review
Advances Colorimetric Detection of Arsenic
Nowadays, arsenic (III) contamination of drinking water is a global issue. Laboratory and instrument-based techniques are typically used to detect arsenic in water, with an accuracy of 1 ppb. However, such detection methods require a laboratory-based environment, skilled labor, and additional costs for setup. As a result, several metal-based nanoparticles have been studied to prepare a cost-effective and straightforward detector for arsenic (III) ions. Among the developed strategies, colorimetric detection is one of the simplest methods to detect arsenic (III) in water. Several portable digital detection technologies make nanoparticle-based colorimetric detectors useful for on-site arsenic detection.
  • 1.8K
  • 30 Jun 2021
Topic Review
Ergot Alkaloids Mycotoxins in Cereals
Mycotoxins are secondary metabolites synthesized by an array of fungal genera, usually Fusarium, Penicillium and Aspergillus.
  • 1.8K
  • 24 May 2021
Topic Review
Approaches for Water Pollution Monitoring
Researchers are continuously rallying to enhance the detection of causal source for water pollution through either conventional or mostly advanced approaches focusing on spectrometry, high-throughput sequencing, and flow cytometry technology among others. From this review’s perspective, each pollution evaluation technology has its own advantages and it would be beneficial for several aspects of pollutants assessments to be combined and established as a complementary package for a better aquatic environmental management in the long run.
  • 1.8K
  • 15 Dec 2020
Topic Review
Screen-Printed Electrodes as Transducers
In the last decades, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as low-cost, disposability, ease of use and portability, which allow fast analysis in point-of-need scenarios. The main characteristics of SPEs as electrochemical transducers for biosensors are described below.
  • 1.8K
  • 13 Apr 2021
Topic Review
Fluorescent Probes in Cellulo Recognitions of Alkaline Phosphatases
Alkaline phosphatase (ALP) is one of the vital phospho-ester bond cleaving biocatalysts that has inevitable significance in cellular systems, viz., early-stage osteoblast differentiation, cell integrity in tissues, bone mineralization, cancer biomarker, liver dysfunction, cellular osmotic pressure, protein folding and many more. Variation from optimal levels of ALP in intra and extracellular fluids can cause severe diseases, including death. Due to these reasons, ALP is considered as a vital biomarker for various preclinical and medical diagnosis. Fluorescence image-based diagnosis is the most widely used method, owing to its simplicity, robustness, non-invasive properties and excellent spatio-temporal resolution (up to the nM/pM level), as compared to conventional analytical techniques, such as the electroanalytical method, nuclear magnetic resonance (NMR) and high-performance liquid chromatography (HPLC). Most of the reviews reported for ALP’s recognition in the literature scarcely explain the structurally related, photophysical and biophysical parameters; and the sub-cellular localizations. Considering these facts, in order to enhance the opto-analytical parameters of fluorescence-based diagnostic materials at the cellular level, herein we have systematically documented recent developments in the opto-analytical capabilities of quencher-free probes for ALP, used in in vitro (biological buffers) to in cellulo conditions, along with in vivo models. 
  • 1.8K
  • 03 Sep 2022
Topic Review
Polyamine Detection Methods
The biogenic aliphatic polyamines (spermine, spermidine, and putrescine) are responsible for numerous cell functions, including cell proliferation, the stabilization of nucleic acid conformations, cell division, homeostasis, gene expression, and protein synthesis in living organisms. The change of polyamine concentrations in the urine or blood is usually related to the presence of malignant tumors and is regarded as a biomarker for the early diagnosis of cancer. Therefore, the detection of polyamine levels in physiological fluids can provide valuable information in terms of cancer diagnosis and in monitoring therapeutic effects. 
  • 1.8K
  • 23 Aug 2022
Topic Review
Graphene Field-Effect Transistor Biosensors in COVID-19 Detection Technology
Coronavirus disease 2019 (COVID-19) is a disease caused by the infectious agent of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Graphene field-effect transistor (GFET) biosensors have become the most promising diagnostic technology for detecting SARS-CoV-2 due to their advantages of high sensitivity, fast-detection speed, label-free operation, and low detection limit.
  • 1.8K
  • 06 Nov 2023
Topic Review
Chromatographic-Based Platforms
Chromatography, which means to show with colors, is certainly among the most important analytical procedures supporting science and human development in the last century. Chromatography is present in the most diverse fields of human activity, spanning from science to the pharmaceutical, chemical, and food industries and the areas of health and the environment. According to the IUPAC definition, chromatography is a physical method of separation in which the components to be separated are distributed between two phases, one of which is stationary (stationary phase) while the other (the mobile phase) moves in a definite direction. In scientific terms, chromatography is not one, but several related techniques able to separate mixtures and it is so powerful that it can be used to separate proteins differing in a single amino acid, compounds differing only in the spatial orientation of a functional group or a volatile compound in a mixture.
  • 1.7K
  • 25 Aug 2022
Topic Review
Pulsed Electric Field Applications for Food Waste Extraction
The food processing industry is a continuously developing sector that uses innovative technologies to efficiently process food products. During processing, food industries generate substantial amounts of by-products in the form of waste materials. This food waste consists of organic matter rich in bioactive compounds, such as polyphenols, carotenoids, and flavonoids. Improper management of food waste can adversely affect both the environment and human health, leading to environmental pollution and the release of greenhouse gas emissions. Thus, proper food waste management has become an urgent global issue. The presence of bioactive compounds (mainly polyphenols, flavonoids, and anthocyanins, but also carotenoids, alkaloids, proteins, lipids, and carbohydrates) in food waste holds the potential to transform them into valuable resources. Several sectors, including food and energy, have recognized food waste as an innovative source. 
  • 1.7K
  • 20 Nov 2023
Topic Review
Electrochemical Sensors for Formaldehyde
Formaldehyde, a ubiquitous indoor air pollutant, plays a significant role in various biological processes, posing both environmental and health challenges.
  • 1.7K
  • 17 Jan 2024
Topic Review
Interaction of Water and Solutes
Water plays an important role in chemical and biological processes. The interaction of water and solutes is of great significance for understanding the properties of aqueous solutions or bio-systems.
  • 1.7K
  • 08 Feb 2022
Topic Review
Potentiometry and Ion-Selective Electrodes
Potentiometry is a highly selective and relatively cheap method that allows achieving low detection limits and a very wide dynamic range of sensors (up to eight orders of units). The principle of the method is to measure the electromotive force (EMF) of a cell made of two types of electrodes: a reference electrode whose potential has to necessarily be constant regardless of the composition and concentration of the sample, and an indicator (working) electrode whose potential changes depending on the activity of the main ion present in the sample solution to which the ion-selective membrane is sensitive.
  • 1.7K
  • 04 Jul 2023
Topic Review
The Chemical Fingerprint of Fortified Wines
The chemical fingerprint of fortified wines is very complex and fascinating, being constituted by several hundred volatile and non-volatile chemical groups, such as terpenoids, pyrazines, esters, alcohols, acids, furanic compounds, phenolic compounds, and organic acids, among others. These chemical groups were present in fortified wines at different volatilities, polarities, and concentration ranges, from a few ng/L to mg/L. However, the quality of wine also depends on several parameters, such as grape variety, vineyard location, terroir, and vinification conditions (e.g., fermentation, ageing), among others. 
  • 1.7K
  • 12 Jul 2023
Topic Review
A Graphene-PEDOT
A graphene and poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) modified conductive paper-based electrochemical impedance spectroscopy (EIS) aptasensor has been successfully fabricated by a simple and continuous coating process. A graphene/PEDOT:PSS modified paper electrode forms the nanocomposite providing a conductive and sensitive substrate for further aptamer functionalization of the biosensor. This low-cost paper-based aptasensor exhibits its sensitivity to carcinoembryonic antigens (CEA) in standard buffer solutions and human serum samples in a linear range of 0.77–14 ng·mL−1. The limit of detection (LOD) is found to be 0.45 ng·mL−1 and 1.06 ng·mL−1 for CEA in both samples, separately. This aptamer-based sensing device was also evaluated and received a good correlation with the immunoassay detection method. The proposed paper-based aptasensor has demonstrated its potential as a rapid simple point-of-care analytical platform for early cancer diagnosis in less developed areas where manufacturing facilities, analytical instruments, and trained specialists are limited.
  • 1.7K
  • 01 Nov 2020
Topic Review
QNMR for Reference Material Preparation
Quantitative nuclear magnetic resonance (qNMR) has been used as a purity determination method for reference material development, and many related measurement techniques have been designed to acquire accurate and reliable results.
  • 1.6K
  • 18 Feb 2021
Topic Review
Analytical Methods for Codeine Determination
Codeine is derived from morphine, an opioid analgesic, and has weaker analgesic and sedative effects than the parent molecule. This weak opioid is commonly used in combination with other drugs for over-the-counter cough relief medication. Due to the psychoactive properties of opioid drugs, the easily obtained codeine often becomes subject to misuse. Codeine misuse has emerged as a concerning public health issue due to its associated adverse effects such as headache, nausea, vomiting, and hemorrhage. Thus, it is very important to develop reliable analytical techniques to detect codeine for both quality control of pharmaceutical formulations and identifying drug misuse in the community. This review aims to provide critical outlooks on analytical methods napplicable to the determination of codeine.
  • 1.6K
  • 11 Mar 2021
Topic Review
Cyclodextrins
Cyclodextrins (CDs) are a family of cyclic oligosaccharides artificially obtained from the union of glucose monomers linked by α-1,4 glycosidic bonds. They are shaped as truncated cones due to the constitutional asymmetry of the glucopyranose rings. Their central cavity of the cone is lined with the skeletal carbons and ethereal oxygen of the glucose residues, which produce a hydrophobic zone that is capable of forming inclusion complexes with a variety of molecules. For this reason, a number of CDs have become everyday commodities in separation sciences, and so chemical aspects such as their structures or their intercalation mode have been more profoundly studied. The structural aspects of CDs can enable the improvement of different chromatographic separations, the enhancement of sensitivity, and the accuracy of analytical methods. 
  • 1.6K
  • 08 Jan 2021
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