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1.
Biosensors (Basel) ; 14(4)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38667156

ABSTRACT

Covalent organic frameworks (COFs) are porous crystals that have high designability and great potential in designing, encapsulating, and immobilizing nanozymes. COF nanozymes have also attracted extensive attention in analyte sensing and detection because of their abundant active sites, high enzyme-carrying capacity, and significantly improved stability. In this paper, we classify COF nanozymes into three types and review their characteristics and advantages. Then, the synthesis methods of these COF nanozymes are introduced, and their performances are compared in a list. Finally, the applications of COF nanozymes in environmental analysis, food analysis, medicine analysis, disease diagnosis, and treatment are reviewed. Furthermore, we also discuss the application prospects of COF nanozymes and the challenges they face.


Subject(s)
Metal-Organic Frameworks , Metal-Organic Frameworks/chemistry , Biosensing Techniques , Nanostructures , Chemistry, Analytic , Food Analysis , Chemistry Techniques, Analytical/methods
3.
Sensors (Basel) ; 23(17)2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37687792

ABSTRACT

Green Chemistry is a vital and crucial instrument in achieving pollution control, and it plays an important role in helping society reach the Sustainable Development Goals (SDGs). NIR (near-infrared spectroscopy) has been utilized as an alternate technique for molecular identification, making the process faster and less expensive. Near-infrared diffuse reflectance spectroscopy and Machine Learning (ML) algorithms were utilized in this study to construct identification and classification models of bacteria such as Escherichia coli, Salmonella enteritidis, Enterococcus faecalis and Listeria monocytogenes. Furthermore, divide these bacteria into Gram-negative and Gram-positive groups. The green and quick approach was created by combining NIR spectroscopy with a diffuse reflectance accessory. Using infrared spectral data and ML techniques such as principal component analysis (PCA), hierarchical cluster analysis (HCA) and K-Nearest Neighbor (KNN), It was feasible to accomplish the identification and classification of four bacteria and classify these bacteria into two groups: Gram-positive and Gram-negative, with 100% accuracy. We may conclude that our study has a high potential for bacterial identification and classification, as well as being consistent with global policies of sustainable development and green analytical chemistry.


Subject(s)
Algorithms , Spectroscopy, Near-Infrared , Bacteria , Chemistry, Analytic , Escherichia coli , Machine Learning
4.
Anal Methods ; 15(36): 4627-4639, 2023 09 21.
Article in English | MEDLINE | ID: mdl-37694570

ABSTRACT

There is a pressing need for the development of greener liquid chromatographic bioanalytical methods for antidiabetic drugs for plasma monitoring and revisiting patients' dosage regimens. Besides, analytical methods are also needed for the quality assurance of finished drug products and regulatory approval. Therefore, the present review focuses on the reported liquid chromatographic methods (LC and LC-MS/MS) that are applied for quality control, forced degradation, and pharmacokinetic studies of a newer antidiabetic agent, canagliflozin (CNG). These reported studies are summarized based on liquid chromatographic separation parameters, such as column dimensions, mobile-phase compositions, flow rate, and use of different detection systems (UV, PDA, and mass spectrometry). The sample pretreatment of biological fluids, which is important for minimizing the matrix effect, is dealt with separately. Liquid-liquid extraction was found to be the most preferred methodology adopted for sample pretreatment followed by the solid-phase extraction technique. However, miniaturized novel pretreatment methods are untraceable in the literature for the extraction of CNG. Special emphasis is paid to the assessment of the greenness profiles of the reported analytical methods for the consideration of sustainable development and green analytical chemistry. Based on the National Environmental Method Index (NEMI) assessment tool, most of the reported studies fulfilled around half of the parameters and were found to be about 50% greener. It is proposed that toxic or hazardous solvents, such as acetonitrile or methanol, should be replaced with greener and environmentally friendly solvents. Thus, there is a need to develop more robust, efficient, and greener liquid chromatographic methods for the determination of CNG in biological fluids and drug products.


Subject(s)
Canagliflozin , Tandem Mass Spectrometry , Humans , Chromatography, Liquid , Chemistry, Analytic , Hypoglycemic Agents , Solvents
5.
Bioanalysis ; 15(15): 937-954, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37638635

ABSTRACT

Microextraction techniques have attracted the attention of many researchers working in the field of bioanalysis due to their unique advantages, mainly in downsizing the scale of sample preparation steps. In parallel, analytical derivatization offers a powerful combination in terms of additional sensitivity, selectivity and compatibility with modern separation techniques. The aim of this review is to discuss the most recent advances in bioanalytical sample preparation based on the combination of microextraction and analytical derivatization. Both innovative fundamental reports and analyte-targeted applications are included and discussed. Dispersive liquid-liquid extraction and solid-phase microextraction are the most common techniques that typically combined with derivatization, while the development of novel and greener protocols is receiving substantial consideration in the field of analytical chemistry.


Subject(s)
Chemistry, Analytic , Liquid-Liquid Extraction , Humans , Research Personnel , Solid Phase Microextraction , Specimen Handling
6.
Sci Rep ; 13(1): 11792, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37479792

ABSTRACT

An in-line smartphone connected to a screen-printed selective electrode hand-held device was used to determine the concentration of distigmine bromide (DB) in its pure and dosage forms as well as its degradation kinetics by continuously measuring the change in the produced emf over time. The main objective, supported by the data presented, is to produce a highly reliable smartphone integrated selective sensor as a portable analyzer with potential high cloud connectivity combining a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles. The choice of ionophore used in this approach was guided by computation and the data obtained was compared with traditional analytical techniques. DB, for which there are no previously reported stability-indicating methods and for which four novel such methods are proposed here, was selected as a model drug for this work. At-line UV-spectrophotometry DB assay was obtained by measuring the difference between the spectra of the degradation product and the same concentration of intact drug. The degradation kinetics were studied by this method through tracking the decrease of DB absorbance and/or the increase of a generated degradation product signal over time. Off-line separation based HPLC and TLC stability-indicating methods for DB were also presented. All methods employed in this work were validated for accuracy, precision, specificity, repeatability, linearity, range, detection and quantification limits according to the ICH guidelines and were applied to the analysis of laboratory prepared mixtures as well as commercial products. While all methods proposed were shown to be highly reliable, the smartphone integrated selective sensor is highlighted as a portable analyzer with potential high cloud connectivity and was shown to combine a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles.


Subject(s)
Biological Assay , Chemistry, Analytic , Kinetics , Electrodes , Pharmaceutical Preparations
8.
Eur Biophys J ; 52(4-5): 233-266, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36792822

ABSTRACT

Proper interpretation of analytical ultracentrifugation (AUC) data for purified proteins requires ancillary information and calculations to account for factors such as buoyancy, buffer viscosity, hydration, and temperature. The utility program SEDNTERP has been widely used by the AUC community for this purpose since its introduction in the mid-1990s. Recent extensions to this program (1) allow it to incorporate data from diffusion as well as AUC experiments; and (2) allow it to calculate the refractive index of buffer solutions (based on the solute composition of the buffer), as well as the specific refractive increment (dn/dc) of proteins based on their composition. These two extensions should be quite useful to the light scattering community as well as helpful for AUC users. The latest version also adds new terms to the partial specific volume calculations which should improve the accuracy, particularly for smaller proteins and peptides, and can calculate the viscosity of buffers containing heavy isotopes of water. It also uses newer, more accurate equations for the density of water and for the hydrodynamic properties of rods and disks. This article will summarize and review all the equations used in the current program version and the scientific background behind them. It will tabulate the values used to calculate the partial specific volume and dn/dc, as well as the polynomial coefficients used in calculating the buffer density and viscosity (most of which have not been previously published), as well as the new ones used in calculating the buffer refractive index.


Subject(s)
Chemistry, Analytic , Scattering, Radiation , Ultracentrifugation , Ultracentrifugation/methods , Databases, Factual , Chemistry, Analytic/standards , Proteins/chemistry
9.
Anal Chem ; 95(1): 1-2, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36625103
10.
Crit Rev Anal Chem ; 53(1): 27-45, 2023.
Article in English | MEDLINE | ID: mdl-34152894

ABSTRACT

Chiral separation has attracted much attention for basic research and industrial applications in analytical chemistry. Generally, chiral separations use natural or artificial chiral-based materials as adsorbents. To improve the precision and efficiency of chiral separation, focus has shifted from natural and synthetic adsorbents to binary combinations of materials. This review specifically summarizes the significant advancements made in natural and artificial chiral adsorbents as promising candidates for diverse drug and biomolecule separation applications as well as the remaining drawbacks and challenges for research on chiral separations. The mechanisms of chiral-based recognition and separation and history and development of natural and artificial chiral-based systems are the focus of this review. Future directions in natural and artificial chiral-based systems for practical separations and other applications are also presented.


Subject(s)
Chemistry, Analytic , Stereoisomerism
12.
Chem Commun (Camb) ; 59(4): 434-437, 2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36515131

ABSTRACT

The amplification of weak molecular signals to visible output could provide a gateway to the macroscopic world. In this context, supramolecular interfaces were designed by depositing macrocyclic "host" molecules in a multilayer film that can be utilized to discriminate isomers by their fluid flow response upon "host-guest" molecular recognition.


Subject(s)
Isomerism , Stereoisomerism , Chemistry, Analytic
13.
Biomédica (Bogotá) ; 43(Supl. 1): 229-244, 2023. tab, graf
Article in Spanish | LILACS | ID: biblio-1533889

ABSTRACT

Introducción. La eficiencia de una metodología para analizar una sustancia farmacológica puede verse afectada por las condiciones reales del laboratorio de cada país, incluyendo el clima. Por esta razón, se requiere validar el método con las pautas recomendadas para ello y optimizar el proceso, para asegurar el éxito y la confianza en los resultados. Objetivo. Validar una metodología para la cuantificación simultánea del fluconazol (materia prima) y sus impurezas orgánicas mediante cromatografía líquida de alta resolución con detector de arreglo de diodos en condiciones de clima tropical y con todos los requisitos normativos. Materiales y métodos. Se hicieron pruebas previas a la validación del método: idoneidad del sistema, estudio de filtros, límite de cuantificación, ausencia del error sistemático, estudios de degradación forzada y estabilidad de las soluciones. Además, se validaron: la especificidad, la linealidad, la exactitud, la precisión y la robustez. Resultados. La pureza espectral del método se logró al obtener la separación de los productos de degradación de los picos de los analitos. La estabilidad de las soluciones no se vio afectada, en la frecuencia evaluada de 24 horas, a temperatura ambiente y de refrigeración. Se obtuvo una linealidad con coeficientes de correlación mayores o iguales a 0,999 para la valoración y mayores o iguales a 0,997 para las impurezas. La recuperación estuvo en el rango de 98 a 102,0 % de fluconazol, con una exactitud entre el 80 y el 120 % para las impurezas. El factor de repetibilidad y reproducibilidad no superó la desviación estándar relativa del 2,0 % para la valoración y, la del 5,0 %, para las impurezas, lo cual mostró una solidez adecuada del método. Además, se obtuvo un tiempo corto de ejecución del análisis, lo que permitió la rápida determinación de la calidad de la materia prima. Conclusión. Se demostró que el método de cuantificación de fluconazol, validado por cromatografía líquida de alta resolución con detector de arreglo de diodos, es lo suficientemente selectivo, preciso, exacto, lineal y robusto; además, es capaz de generar resultados analíticos veraces en condiciones de uso reales, incluyendo el clima tropical de Colombia.


Introduction. The real laboratory conditions of each country, including climate, can affect the method's efficiency in analyzing a pharmacological substance. Thus, it is necessary to validate the process according to the corresponding guidelines and optimize it to ensure success and confidence in the results. Objective. The objective was to validate a methodology for fluconazole and its organic impurities quantification in raw material using high-performance liquid chromatography, with a diode array detector, under tropical climate conditions, and complying with all regulatory requirements. Materials and methods. We performed pre-validation tests of the method consisting of system adequacy, filters study, quantification limit, absence of systematic error, forced degradation studies, and solutions stability. In addition, we validated the specificity, linearity, accuracy, precision, and robustness of the system. Results. Separation of the degradation products from the analyte peaks allowed the achievement of the method's spectral purity. The solution's stability was not affected during the evaluated time (24 hours) at room temperature and under refrigeration. Linearity resulted in correlation coefficients greater than or equal to 0.999 for the evaluation and greater than or equal to 0.997 for impurities. We obtained a fluconazole recovery varying from 98 to 102% with an accuracy between 80 to 120% for impurities detection. The repeatability and reproducibility factor did not exceed a relative standard deviation of 2.0% for the evaluation and of 5.0% for the impurities, demonstrating the adequate robustness of the method. In addition, a short analysis execution time allowed the quick determination of the raw material quality. Conclusion. We demonstrated that the fluconazole quantification method validated by high-performance liquid chromatography is sufficiently selective, precise, exact, linear, and robust to generate accurate analytical results under real conditions, including the tropical climate of Colombia.


Subject(s)
Fluconazole , Evaluation Studies as Topic , Drug Contamination , Chromatography, Liquid , Validation Study , Chemistry, Analytic
14.
Sensors (Basel) ; 22(23)2022 Dec 05.
Article in English | MEDLINE | ID: mdl-36502213

ABSTRACT

Sucrose is a primary metabolite in plants, a source of energy, a source of carbon atoms for growth and development, and a regulator of biochemical processes. Most of the traditional analytical chemistry methods for sucrose quantification in plants require sample treatment (with consequent tissue destruction) and complex facilities, that do not allow real-time sucrose quantification at ultra-low concentrations (nM to pM range) under in vivo conditions, limiting our understanding of sucrose roles in plant physiology across different plant tissues and cellular compartments. Some of the above-mentioned problems may be circumvented with the use of bio-compatible ligands for molecular recognition of sucrose. Nevertheless, problems such as the signal-noise ratio, stability, and selectivity are some of the main challenges limiting the use of molecular recognition methods for the in vivo quantification of sucrose. In this review, we provide a critical analysis of the existing analytical chemistry tools, biosensors, and synthetic ligands, for sucrose quantification and discuss the most promising paths to improve upon its limits of detection. Our goal is to highlight the criteria design need for real-time, in vivo, highly sensitive and selective sucrose sensing capabilities to enable further our understanding of living organisms, the development of new plant breeding strategies for increased crop productivity and sustainability, and ultimately to contribute to the overarching need for food security.


Subject(s)
Carbon , Sucrose , Chemistry, Analytic , Crop Production , Recognition, Psychology
15.
Anal Chem ; 94(44): 15464-15471, 2022 11 08.
Article in English | MEDLINE | ID: mdl-36281827

ABSTRACT

A major obstacle for reusing and integrating existing data is finding the data that is most relevant in a given context. The primary metadata resource is the scientific literature describing the experiments that produced the data. To stimulate the development of natural language processing methods for extracting this information from articles, we have manually annotated 100 recent open access publications in Analytical Chemistry as semantic graphs. We focused on articles mentioning mass spectrometry in their experimental sections, as we are particularly interested in the topic, which is also within the domain of several ontologies and controlled vocabularies. The resulting gold standard dataset is publicly available and directly applicable to validating automated methods for retrieving this metadata from the literature. In the process, we also made a number of observations on the structure and description of experiments and open access publication in this journal.


Subject(s)
Natural Language Processing , Semantics , Research Design , Chemistry, Analytic
16.
Ambix ; 69(4): 399-419, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36250926

ABSTRACT

This paper examines the identification of chemical elements using mineral analysis, focusing on the controversy surrounding the "tantalum metals" between 1801 and 1866. Of these metals, only tantalum and niobium are still recognised as elements today; the discovery claims of columbium, pelopium, ilmenium and dianium were all retracted or refuted. Despite the theoretical and institutional changes that chemistry underwent during this time, the debates on the tantalum metals point towards a continuity in the identification of metals. For most of the nineteenth century, chemists continued to use the same types of analytical procedures as their mid-eighteenth-century predecessors. These analytical methods enabled the identification of metals based on the chemical behaviour of their compounds, without requiring their isolation in the form of simple substances (that is, as metals). Accordingly, the central questions in all of the debates on the tantalum metals were the correct identification of the properties of compounds and the elimination of impurities, rather than the simplicity of the new metals. The story of the tantalum metals therefore illustrates the fact that, despite the definition of chemical elements as simple substances, the discovery of new (metallic) elements only rarely coincided with the isolation of new simple substances.


Subject(s)
Niobium , Tantalum , Tantalum/chemistry , Niobium/chemistry , Metals , Chemistry, Analytic
17.
J Chromatogr A ; 1681: 463460, 2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36070641

ABSTRACT

Inherent in the use of almost any analytical technique is the need to improve the separation efficiency and extract purity. One possibility for enhancing analytical methods is the application of substances / materials that functionalize components of the separation system. They interact with the material to be modified, either permanently or temporarily. Typically, organic solvents or salts are used for this purpose. The ionic liquids (ILs) are salts that remain in the liquid phase at temperatures below 100 ℃, what gives them advantage compared to traditional modifiers. This paper presents the range of applications of ILs in functionalized materials in analytical chemistry, as presented in publications from the last five years. Several types of techniques in which ILs are used are presented (HPLC, GC, electrophoresis, supported liquid membranes, passive sampling, various modification of solid-phase extraction), along with most interesting exemplary studies. As expected, imidazolium ILs are most commonly used. The application of ILs for functionalization in analytical techniques is extremely useful, but the problem is their cost and the low recovery rate. However, the rapid development in this field of science and the promising results encourage further work on the issue of ILs in functionalized materials.


Subject(s)
Ionic Liquids , Chemistry, Analytic , Chromatography, High Pressure Liquid/methods , Ionic Liquids/chemistry , Salts , Solvents/chemistry
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