Quantum Mechanical Quantitative Nuclear Magnetic Resonance Enables Digital Reference Standards at All Magnetic Fields and Enhances qNMR Sustainability.

Quantum mechanics (QM)-driven terative unctionalized pin nalysis produces HifSA profiles, which encode the complete H spin parameters ("nuclear genotype") of analytes of interest. HifSA profiles enable the establishment of digital reference standards (dRS) that are portable, FAIR (findable - accessible - interoperable - reusable), and fit for the purpose of quantitative H NMR (qHNMR) analysis at any magnetic field. This approach enhances the sustainability of analytical standards.

Purity Determination of Cyclophosphamide Hydrate by Quantitative P-NMR and Method Validation.

Recently, quantitative NMR (qNMR), especially H-qNMR, has been widely used to determine the absolute quantitative value of organic molecules. We previously reported an optimal and reproducible sample preparation method for H-qNMR. In the present study, we focused on a P-qNMR absolute determination method.

Determination of Absolute Purities of Hygroscopic Substances by Quantitative NMR Analysis for the Standardization of Quantitative Reagents in the Japanese Pharmacopoeia (Part 2).

As a new absolute quantitation method for low-molecular compounds, quantitative NMR (qNMR) has emerged. In the Japanese Pharmacopoeia (JP), 15 compounds evaluated by qNMR are listed as reagents used as the HPLC reference standards in the assay of crude drug section of the JP. In a previous study, we revealed that humidity affects purity values of hygroscopic reagents and that (i) humidity control before and during weighing is important for a reproducible preparation and (ii) indication of the absolute amount (not purity value), which is not affected by water content, is important for hygroscopic products determined by qNMR.

Unique Usage of a Classical Selective Homodecoupling Sequence for High-Resolution Quantitative H NMR.

Classical selective homodecoupling was used in a H NMR purity assay to improve accuracy by overcoming spectral overlaps due to H-H spin coupling. Dummy irradiation at a specific frequency was used in addition to irradiation at a H resonance of the analyte to avoid irradiation bias. The method was validated in a H NMR purity assay of high-purity diethyl phthalate (National Metrology Institute of Japan Certified Reference Material (NMIJ CRM), purity: 99.

[Determination of Absolute Purities of Hygroscopic Substances by Quantitative NMR Analysis for the Standardization of Quantitative Reagents in the Japanese Pharmacopoeia (Part 1)].

Quantitative NMR (qNMR) has been developed as an absolute quantitation method to determine the purity or content of organic compounds including marker compounds in crude drugs. The "qNMR test" has been introduced into the crude-drug section of the Japanese Pharmacopoeia (JP) for determining the purity of reagents used for the assay in the JP. In Supplement II to the JP 17th edition published in June 2019, fifteen compounds adopted qNMR test were listed as the reagents for the assay.

[Evaluation for Standardization of H Quantitative NMR Spectroscopy by Round Robin Test].

 H quantitative NMR (H qNMR) is known as a powerful tool for determination of analytes without the need for their identical standards, which is eligible to a primary rate method. H qNMR has been already stipulated to an assay for purity determination in Japanese Pharmacopoeia (JP), and then this technique has been also applied in several fields such as pharmaceutical and food sciences. However, there is little information about the accuracy of H qNMR so that the further applications into other fields such as industrial chemistry could be constricted.

[Determination of the Plant Origin of Licorice Oil Extract, a Natural Food Additive, by Principal Component Analysis Based on Chemical Components].

"Licorice oil extract" (LOE) (antioxidant agent) is described in the notice of Japanese food additive regulations as a material obtained from the roots and/or rhizomes of Glycyrrhiza uralensis, G. inflata or G. glabra.

Contribution of glucose to crystallization of phenytoin in injectable dosage form by dilution with infusion fluids.

The crystallization of phenytoin occurring after its dilution with infusion fluid is a major concern in the clinical use of injectable phenytoin. To gain further understanding of the crystallization, this study assessed details of the involvement of glucose in this action. For sample preparation, phenytoin crystals were created by diluting the injectable phenytoin with infusion fluids with different glucose concentrations at different temperature, and then the characteristics of the crystallization (e.

Absolute quantitation of stevioside and rebaudioside A in commercial standards by quantitative NMR.

The extract prepared from the leaves of Stevia rebaudiana BERTONI (Asteraceae) contains sweet steviol glycosides, mainly stevioside and rebaudioside A. Highly purified stevia extracts have become popular worldwide as a natural, low-calorie sweetener. They contain various types of steviol glycosides, and their main components are stevioside and rebaudioside A.

[Absolute quantitation of quercetin and the glycosides in natural food additives by quantitative NMR].

We are developing a simple absolute quantitation method for organic compounds, by means of quantitative nuclear magnetic resonance (qNMR), with traceability to the International System of Units (SI units). The qNMR method was applied to the absolute quantitation of rutin, isoquercitrin and quercetin in natural food additives, rutin (extract), enzymatically decomposed rutin extract and quercetin, and those compounds as commercial reagents. In this study, 1,4-bis-(trimethylsilyl)benzene-d(4) (1,4-BTMSB-d(4)) whose purity was precisely evaluated on the basis of metrology, was newly used as a qNMR reference material, to be added to the sample solution as an internal standard.

[Absolute quantification of carminic acid in cochineal extract by quantitative NMR].

A quantitative NMR (qNMR) method was applied for the determination of carminic acid. Carminic acid is the main component in cochineal dye that is widely used as a natural food colorant. Since several manufacturers only provide reagent-grade carminic acid, there is no reference material of established purity.

Orientational isomerism controlled by the difference in electronic environments of a self-assembling heterodimeric capsule.

Tetrakis(4-hydroxyphenyl)-cavitand 1 and tetra(4-pyridyl)-cavitand 2 self-assemble into a heterodimeric capsule 1.2 via four ArOH..