Raman spectroscopy for forensic pen ink investigation: a review.

The performance of Raman spectroscopy (RS) has improved in recent years due to the significant advantages of its use in various fields, such as archaeology, medicine, foods, and forensics. An aspect of great relevance in forensic investigation is preserving criminal evidence, and nondestructive techniques for analysis are needed. RS has great potential for characterizing pen inks in questioned documents, and it has even been considered promising for trace intersection and dating investigations.

Determination of Carbohydrates in Syngonium podophyllum Biomass by Capillary Electrophoresis After Saccharification Process Under Different Sample Preparation Techniques.

To achieve a more sustainable future, it is crucial to conduct studies on lignocellulosic biomass as a source of carbohydrates, ultimately serving as feedstocks for platform molecules that can be converted into biofuels, biopolymers, and chemicals. Urban residue lignocellulosic biomass, exemplified by Syngonium podophyllum, shows promise as an alternative source. This study employed capillary zone electrophoresis with indirect UV detection as an environmentally friendly method for determining xylose and glucose after treating, depolymerizing, and saccharifying Syngonium biomass.

From capillaries to microchips, green electrophoretic features for enantiomeric separations: A decade review (2013-2022).

Enantioseparation by the electromigration-based method is well-established and widely discussed in the literature. Electrophoretic strategies have been used to baseline resolve complex enantiomeric mixtures, typically using a selector substance into the background electrolyte (BGE) from capillaries to microchips. Along with developing new materials/substances for enantioseparations, it is the concern about the green analytical chemistry (GAC) principles for method development and application.

Nitrite Determination in Environmental Water Samples Using Microchip Electrophoresis Coupled with Amperometric Detection.

Nitrite is considered an important target analyte for environmental monitoring. In water resources, nitrite is the result of the nitrogen cycle and the leaching processes of pesticides based on nitrogenous compounds. A high concentration of nitrite can be associated with intoxication processes and metabolic disorders in humans.

Determination of α- and β-acids in hops by liquid chromatography or electromigration techniques: A critical review.

Hop plays an essential role in brewing beer and its study and analysis is of paramount importance. - and -acids are considered two of the most important hop components. While -acids are associated with the bitter flavor, -acids have antimicrobial effects.

Determination of naphthenic acids in produced water by using microchip electrophoresis with integrated contactless conductivity detection.

This study reports for the first time the use of a microchip electrophoresis (ME) device with integrated capacitively coupled contactless conductivity detection (CD) to analyze naphthenic acids in produced water. A mixture containing 9-anthracenecarboxylic, 1-naphthoic, and benzoic acids was separated and detected using a running buffer composed of 10 mmol L carbonate buffer (pH = 10.2).

Chip-based separation of organic and inorganic anions and multivariate analysis of wines according to grape varieties.

This report describes the use of electrophoresis microchips integrated with contactless conductivity detection for the determination of organic acids and inorganic anions in wine samples and the subsequent classification based on the grape varieties. The best separation was achieved using a buffer composed of 30 mmol L 2-(N-morpholino)ethanesulfonic acid, 15 mmol Ll-histidine and 0.05 mmol L cetyltrimethylammonium bromide (pH 5.

Differentiation of aromatic, bittering and dual-purpose commercial hops from their terpenic profiles: An approach involving batch extraction, GC-MS and multivariate analysis.

Terpenes are one of the main classes of compounds in hops (Humulus lupulus, L). They play an important role in brewing due to their central function, which is related to beer aroma. A screening of terpenes in several commercial hop varieties was carried out by gas chromatography coupled to mass spectrometry after employing a simple, straightforward and high throughput extraction method.

Capillary electromigration methods for fatty acids determination in vegetable and marine oils: A review.

Fatty acids determination is of paramount importance for quality control and suitable labeling of edible oils, required by regulatory agencies in several countries, and fast methods for this determination are worldly desired. This review article aimed to explore the available analytical methods for vegetable and marine oils analyses employing CE, which can be a straightforward and faster alternative than GC methods for fatty acid determination, considering some purposes. CE usually offers the possibility of a rapid analysis with a simple preparation of the sample, without requiring specific columns, which are inherent advantages of the technique.

Improved anti-Cutibacterium acnes activity of tea tree oil-loaded chitosan-poly(ε-caprolactone) core-shell nanocapsules.

The purpose of this study was to develop tea tree oil (TTO)-loaded chitosan-poly(ε-caprolactone) core-shell nanocapsules (NC-TTO-Ch) aiming the topical acne treatment. TTO was analyzed by gas chromatography-mass spectrometry, and nanocapsules were characterized regarding mean particle size (Z-average), polydispersity index (PdI), zeta potential (ZP), pH, entrapment efficiency (EE), morphology by Atomic Force Microscopy (AFM), and anti-Cutibacterium acnes activity. The main constituents of TTO were terpinen-4-ol (37.

Prediction of Fatty Acids in Chocolates with an Emphasis on C18:1 Fatty Acid Positional Isomers Using ATR-FTIR Associated with Multivariate Calibration.

This work aimed to predict C18:1 TFA isomers as well as other groups of fatty acids (saturated, monounsaturated, polyunsaturated, and total TFA) in chocolates by ATR-FTIR and partial least square regression. The quantification of fatty acids in representative samples (white, dark, and milk chocolates) was rapid (<30 s) and did not require derivatization. The optimized models showed satisfactory linear correlations compared to a reference gas chromatographic method.

Nonaqueous electrophoresis on microchips: A review.

The use of organic solvents as electrolytic medium in electrophoresis has become an important alternative for the analysis of compounds that exhibit low or no solubility in water. In recent years, nonaqueous electrophoresis has been extensively explored in conventional capillary systems for different applications. On the other hand, this separation strategy is still not as popular as free solution electrophoresis on chip-based platforms due to the effects of solvent in the background electrolyte on the sample injection, detection performance, and microfluidic platform compatibility.

Fast capillary electrophoresis method for determination of docosahexaenoic and eicosapentaenoic acids in marine oils omega-3 supplements.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential omega-3 fatty acids (FA) in human nutrition. Dietary supplements containing these FA are available in the market and there is a need to assess their quality to prevent frauds. The purpose of this work was to optimize and validate a fast capillary electrophoresis (CE) method to determine EPA and DHA content in marine oils omega-3 supplements.

Baseline separation of α and β-acids homologues and isomers in hop (Humulus lupulus L.) by CD-MEKC-UV.

An alternative method for simultaneous baseline separation of α and β-acids homologues and isomers in hop by CD-MEKC with UV detection was proposed. The optimized background electrolyte was composed of 30 mmol/L sodium tetraborate solution, 45 mmol/L sodium dodecyl sulfate, 20 mmol/L β-cyclodextrin and 10% v/v acetonitrile. The instrumental conditions were evaluated by using a 3 Box-Benhken experimental design.

Synthesis and anticancer evaluation of new lipophilic 1,2,4 and 1,3,4-oxadiazoles.

A series of1,2,4- and 1,3,4-oxadiazole derivatives were synthesized and evaluated for their anticancer activity. Halogenated 1,2,4-oxadiazoles were obtained from benzonitrile and coupled either lipophilic amines or with aminoalcohols. Lipophilic 1,3,4-oxadiazole derivatives were obtained through the Mannich reactions between 5-(aryl)-1,3,4-oxadiazole-2-thiol and alkylated or acylated amines.

Screening method for simultaneous detection of elaidic and vaccenic trans fatty acid isomers by capillary zone electrophoresis.

A novel screening method for the simultaneous detection of elaidic and vaccenic trans fatty acid isomers by CZE-UV was proposed and applied to brazilian spreadable cheese analysis. Optimized background electrolyte was composed by 10 mmol L heptakis (2, 3, 6-tri-o-methyl)-beta cyclodextrin, 24 mmol L sodium tetraborate buffer solution, 45% methanol and 15% acetonitrile. Sample preparation comprised only a saponification reaction and dilution of sample solution before analysis.

Sub-minute determination of rifampicin and isoniazid in fixed dose combination tablets by capillary zone electrophoresis with ultraviolet absorption detection.

A validated sub minute capillary zone electrophoresis method with direct ultraviolet absorption detection for simultaneous determination of isoniazid and rifampicin in fixed-dose combination tablets was developed. Background electrolyte was defined based on the analytes effective mobility curve and it was composed by 20 mmol/L of sodium carbonate/sodium bicarbonate at pH 10.2.

Capillary electrophoresis in association with chemometrics approach for bitterness hop (Humulus lupulus L.) classification.

The precursor compounds related to the bitterness of beer are called α-acids. These compounds are extracted from the hop, which is an important ingredient in the brewing process. These compounds were analyzed by capillary electrophoresis.

Simultaneous determination of aspartame, cyclamate, saccharin and acesulfame-K in powder tabletop sweeteners by FT-Raman spectroscopy associated with the multivariate calibration: PLS, iPLS and siPLS models were compared.

For the first time, a procedure for simultaneous determination of the main artificial sweeteners, aspartame (ASP), cyclamate (CYC), saccharin (SAC), and acesulfame-K (ACSK) by a spectroscopic method associated with the multivariate calibration is proposed. These analytes were quantified in tabletop sweeteners samples using FT-Raman spectroscopy. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used as reference method.