Fabrication and evaluation of magnetic phosphodiesterase-5 linked nanoparticles as adsorbent for magnetic dispersive solid-phase extraction of inhibitors from Chinese herbal medicine prior to ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry analysis

Magnetic materials as adsorbents for the pre-concentration and separation of active ingredients from herbal medicine

Herbal medicine (HM) is crucial in disease management and contains complex compounds with few active pharmacological ingredients, presenting challenges in quality control of raw materials and formulations. Effective separation, identification, and analysis of active components are vital for HM efficacy. Traditional methods like liquid-liquid extraction and solid-phase extraction are time-consuming and environmentally concerning, with limitations such as sorbent issues, pressure, and clogging. Magnetic solid-phase extraction uses magnetic sorbents for targeted analyte separation and enrichment, offering rapid, pressure-free separation. However, inorganic magnetic particles' aggregation and oxidation, as well as lack of selectivity, have led to the use of various coatings and modifications to enhance specificity and selectivity for complex herbal samples. This review delves into magnetic composites in HM pretreatment, specifically focusing on encapsulated or modified magnetic nanoparticles and materials like silica, ionic liquids, graphene family derivatives, carbon nanotubes, metal-organic frameworks, covalent organic frameworks, and molecularly imprinted polymers.

Rapid Screening of Nonalkaloid α-Glucosidase Inhibitors from a Mulberry Twig Extract Using Enzyme-Functionalized Magnetic Nanoparticles Coupled with UPLC-MS/MS

Mulberry twigs are an important source of α-glucosidase inhibitors. To date, research studies on α-glucosidase in mulberry twigs have mainly focused on alkaloids such as 1-deoxynojirimycin (DNJ). Preliminary studies have shown that there may be more active nonalkaloid α-glucosidase inhibitors in mulberry twigs. In this study, we immobilized α-glucosidase on Fe₃O₄@SiO₂ for the first time and rapidly screened four nonalkaloid α-glucosidase inhibitors (kuwanon G, kuwanon C, kuwanon H, and morusin) using ligand fishing technology with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) from the mulberry twig extract of Jialing 20, the excellent artificial triploid variety of mulberry cultivated extensively in Southwest China. The half maximal inhibitory concentrations (IC₅₀) of kuwanon H and kuwanon G were 2.82 ± 0.68 and 2.83 ± 0.31 μM, respectively, with better inhibition activity than that of DNJ (with an IC₅₀ of 7.04 ± 0.82 μM). Meanwhile, the molecular docking results showed that the action sites of these two isopentenyl flavonoids on α-glucosidase were different from that of DNJ. In brief, this work is beneficial to discovering new α-glucosidase inhibitors from mulberry twigs quickly and accurately and provides a theoretical basis for the mulberry twig extract as a functional food or a natural hypoglycemic drug source, as well as a reference for directional breeding of mulberry, which greatly improves the exploitation and utilization value of mulberry twigs as an agricultural byproduct in the fields of agricultural production, functional food, and natural medicine.

LABEL-FREE BIO-AFFINITY MASS SPECTROMETRY FOR SCREENING AND LOCATING BIOACTIVE MOLECULES

Despite the recent increase in the development of bioactive molecules in the drug industry, the enormous chemical space and lack of productivity are still important issues. Additional alternative approaches to screen and locate bioactive molecules are urgently needed. Label-free bio-affinity mass spectrometry (BA-MS) provides opportunities for the discovery and development of innovative drugs. This review provides a comprehensive portrayal of BA-MS techniques and of their applications in screening and locating bioactive molecules. After introducing the basic principles, alongside some application notes, the current state-of-the-art of BA-MS-assisted drug discovery is discussed, including native MS, size-exclusion chromatography-MS, ultrafiltration-MS, solid-phase micro-extraction-MS, and cell membrane chromatography-MS. Finally, several challenges and limitations of the current methods are summarized, with a view to potential future directions for BA-MS-assisted drug discovery. © 2019 John Wiley & Sons Ltd. Mass Spec Rev.

Greenness of magnetic nanomaterials in miniaturized extraction techniques: A review

Green analytical chemistry principles should be followed, as much as possible, and particularly during the development of analytical sample preparation methods. In the past few years, outstanding materials such as ionic liquids, metal-organic frameworks, carbonaceous materials, molecularly imprinted materials, and many others, have been introduced in a wide variety of miniaturized techniques in order to reduce the amount of solvents and sorbents required during the analytical sample preparation step while pursuing more efficient extraction methods. Among them, magnetic nanomaterials (MNMs) have gained special attention due to their versatile properties. Mainly, their ability to be separated from the sample matrix using an external magnetic field (thus enormously simplifying the entire process) and their easy combination with other materials, which implies the inclusion of a countless number of different functionalities, highly specific in some cases. Therefore, MNMs can be used as sorbents or as magnetic support for other materials which do not have magnetic properties, the latter permiting their combination with novel materials. The greenness of these magnetic sorbents in miniaturized extractions techniques is generally demonstrated in terms of their ease of separation and amount of sorbent required, while the nature of the material itself is left unnoticed. However, the synthesis of MNMs is not always as green as their applications, and the resulting MNMs are not always as safe as desired. Is the analytical sample preparation field ready for using green magnetic nanomaterials? This review offers an overview, from a green analytical chemistry perspective, of the current state of the use of MNMs as sorbents in microextraction strategies, their preparation, and the analytical performance offered, together with a critical discussion on where efforts should go.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Medicinal Plant Analysis: A Historical and Regional Discussion of Emergent Complex Techniques

The analysis of medicinal plants has had a long history, and especially with regard to assessing a plant's quality. The first techniques were organoleptic using the physical senses of taste, smell, and appearance. Then gradually these led on to more advanced instrumental techniques. Though different countries have their own traditional medicines China currently leads the way in terms of the number of publications focused on medicinal plant analysis and number of inclusions in their Pharmacopoeia. The monographs contained within these publications give directions on the type of analysis that should be performed, and for manufacturers, this typically means that they need access to more and more advanced instrumentation. We have seen developments in many areas of analytical analysis and particularly the development of chromatographic and spectroscopic methods and the hyphenation of these techniques. The ability to process data using multivariate analysis software has opened the door to metabolomics giving us greater capacity to understand the many variations of chemical compounds occurring within medicinal plants, allowing us to have greater certainty of not only the quality of the plants and medicines but also of their suitability for clinical research. Refinements in technology have resulted in the ability to analyze and categorize plants effectively and be able to detect contaminants and adulterants occurring at very low levels. However, advances in technology cannot provide us with all the answers we need in order to deliver high-quality herbal medicines and the more traditional techniques of assessing quality remain as important today.

Green construction of Fe3O4@GC submicrocubes for highly sensitive magnetic dispersive solid-phase extraction of five phthalate esters in beverages and plastic bottles

A well-designed core-shelled Fe₃O₄@graphitic carbon (Fe₃O₄@GC) submicrocube was in situ constructed in a simple, relatively green and eco-friendly ways basing on one-step pyrolysis of low-cost waste napkins-coated Fe₂O₃ submicrocubes. The Fe₃O₄@GC submicrocubes showed unique architectures where in situ generated thin graphitic carbon layer wrapped on the surface of Fe₃O₄, resulting in excellent affinity to five phthalate esters (PAEs), good reusability and rapid magnetic separation, therefore were employed as magnetic dispersive solid-phase extraction material combined with HPLC to simultaneously detect five trace PAEs in beverages and plastic bottles. Under optimized conditions, recoveries (80.0%-112.8%), precision (RSDs ≤ 8.8%), and limits of detection (LODs) for beverages (0.09-0.28 μg L^-1) and plastic bottles (0.01-0.03 μg g^-1) were obtained. This work not only establishes an effective method for simultaneous determination of five PAEs, but also opens up a new strategy to design/construct magnetic graphitic carbon-encapsulated core-shell materials using low-cost/recyclable napkins as carbon source.

Magnetic nanocellulose from olive industry solid waste for the effective removal of methylene blue from wastewater

The work shown in this article demonstrate a novel example of converting olive industry solid waste (OISW) into a magnetic cellulose nanocrystalline (MNCs) to serve as selective magnetic sorbents for methylene blue. Olive industry solid waste contains about 40% cellulose. The cellulose was extracted in a powder form from olive industry solid waste by subjecting it to a multistep pulping and bleaching process. The extracted powder cellulose was then converted to nanocrystalline cellulose (NCs) by acid hydrolysis. The NCs were then treated with a solution of FeCl₃.6H₂O, FeSO₄, and H₂O by a colloidal suspension method which produced free-flowing porous MNCs. The produced MNCs are characterized by several spectroscopic and analytical techniques such as SEM, TEM, XRD, FTIR VSM, and TGA. The efficiency of the three polymers cellulose powder, NCs, and MNCs toward extracting methylene blue (MB) from water was evaluated. Cellulose powder and NCs showed acceptable tendency for methylene blue. However, MNCs showed excellent extraction efficiency toward MB. The thermodynamic studies revealed a spontaneous adsorption of MB by MNCs at various temperatures. The spontaneous adsorption could be attributed to the electrostatic interaction and H-bonding between MNCs and MB. However, the interaction between cellulose, NCs, and MB is limited to the H-bonding.