Electrochemical Oxidation as a Tool for Generating Vitamin D Metabolites

Sample transformation in online separations: how chemical conversion advances analytical technology

While the advent of modern analytical technology has allowed scientists to determine the complexity of mixtures, it also spurred the demand to understand these sophisticated mixtures better. Chemical transformation can be used to provide insights into properties of complex samples such as degradation pathways or molecular heterogeneity that are otherwise unaccessible. In this article, we explore how sample transformation is exploited across different application fields to empower analytical methods. Transformation mechanisms include molecular-weight reduction, controlled degradation, and derivatization. Both offline and online transformation methods have been explored. The covered studies show that sample transformation facilitates faster reactions (e.g. several hours to minutes), reduces sample complexity, unlocks new sample dimensions (e.g. functional groups), provides correlations between multiple sample dimensions, and improves detectability. The article highlights the state-of-the-art and future prospects, focusing in particular on the characterization of protein and nucleic-acid therapeutics, nanoparticles, synthetic polymers, and small molecules.

Lemon extract supported green synthesis of bimetallic CuO/Ag nanoporous materials for sensitive detection of vitamin D3

In modern era, deficiency of Vitamin D3 is predominantly due to limited exposure to sunlight and UV radiation resulting from indoor lifestyles. Several studies have revealed that vitamin D deficiency can lead to chronic vascular inflammation, diabetes mellitus, hypertension, congestive left ventricular hypertrophy, and heart failure. This study introduces a green synthesis of novel bimetallic nanoporous composite, CuO/Ag using lemon extract. The synthesized nanoporous material, CuO/Ag@lemon extract was characterized using several analytical techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The CuO/Ag@lemon extract nanoparticles were immobilized on glassy carbon electrode (GCE) to prepare modified CuO/Ag@lemon extract-GCE interface. The electrocatalytic and electrochemical properties investigation was carried out on the modified electrode. using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and amperometry for detecting of Vitamin D3. The DPV method displayed a linear response range of 0.02-22.5 µM with a detection limit of 2.62 nM, while the amperometric method showed a broader linear range of 0.25-23.25 µM with a detection limit of 2.70 nM with 82% modified electrode stability. The designed electrode exhibited a positive response to the inclusion of Vitamin D3 with electro-oxidation, reaching steady-state within 3.4 s, with 87% reproducibility within a day. The proposed method offers a rapid and sensitive platform for detection of Vitamin D3 with minimal interference from other molecules. The early diagnosis of Vitamin D3 deficiency using modified electrodes allows for early treatment, thereby preventing severe health complications.

Effects of Dietary Components on Mast Cells: Possible Use as Nutraceuticals for Allergies?

Allergic diseases affect an estimated 30 percent of the world's population. Mast cells (MC) are the key effector cells of allergic reactions by releasing pro-inflammatory mediators such as histamine, lipid mediators, and cytokines/chemokines. Components of the daily diet, including certain fatty acids, amino acids, and vitamins, as well as secondary plant components, may have effects on MC and thus may be of interest as nutraceuticals for the prevention and treatment of allergies. This review summarizes the anti-inflammatory effects of dietary components on MC, including the signaling pathways involved, in in vitro and in vivo models. Butyrate, calcitriol, kaempferol, quercetin, luteolin, resveratrol, curcumin, and cinnamon extract were the most effective in suppressing the release of preformed and de novo synthesized mediators from MC or in animal models. In randomized controlled trials (RCT), vitamin D, quercetin, O-methylated epigallocatechin gallate (EGCG), resveratrol, curcumin, and cinnamon extract improved symptoms of allergic rhinitis (AR) and reduced the number of inflammatory cells in patients. However, strategies to overcome the poor bioavailability of these nutrients are an important part of current research.

A manganese dioxide nanoparticle-bimetallic metal organic framework composite for selective and sensitive detection of vitamin D3 in human plasma

For the first time a metal organic framework nanomaterial has been developed comprising manganese dioxide nanoparticle and iron and zinc metal ions interlinked with each other via terephthalic acid. The framework shape was identified as an elongated hexagonal nanorod (TEM) with varying functional groups (FT-IR) and diffraction patterns (XRD). The framework nanocomposite as such in aqueous acidic electrolyte solution has displayed an excellent conductivity (redox behavior) and surface excess (3.08 × 10-8 cm-2). Under the optimized conditions (0.1 M H2SO4 as electrolyte, 50 mV/s scan rate, +1.26 V (vs Ag/AgCl)), the metal organic framework coated electrode has selectively identified vitamin D3 (VD3) in the presence of various other interfering molecules and displayed excellent limit of detection (1.9 ng mL-1). The developed sensor has been applied to the determination of VD3 in extracted human plasma samples (RSD of 0.3-2.6 % and recovery of 96-102 %), and the obtained VD3 values are similar to HPLC-UV method.