A quantitative ¹H nuclear magnetic resonance (qHNMR) method for assessing the purity of iridoids and secoiridoids.

A quantitative ¹H nuclear magnetic resonance (qHNMR) method for assessing the purity of iridoids and secoiridoids.

Fitoterapia (2014-12-17)

Zeyun Li, Edward Welbeck, Li Yang, Chunyong He, Haijun Hu, Ming Song, Kaishun Bi, Zhengtao Wang

ABSTRACT

This paper utilized a quantitative (1)H nuclear magnetic resonance (qHNMR) method for assessing the purity of iridoids and secoiridoids. The method was fully validated, including specificity, linearity, accuracy, precision, reproducibility, and robustness. For optimization of experimental conditions, several experimental parameters were investigated, including relaxation delay (D1), scan numbers (NS) and power length (PL1). The quantification was based on the area ratios of H-3 from analytes relative to aromatic protons from 1,4-dinitrobenzene (internal standard) with methanol-d4 as solvent. Five iridoids and secoiridoids (sweroside, swertiamarin, gentiopicroside, geniposide, genipin) were analyzed. Furthermore, the results were validated by the high performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) method. It can be concluded that the qHNMR method was simple, rapid, and accurate, providing a reliable and superior method for assessing the purity of iridoids and secoiridoids.

MATERIALS

Product Number

Brand

Product Description

535435

Sigma-Aldrich

Methanol-d₄, "100%", ≥99.96 atom % D, contains 0.03 % (v/v) TMS

569534

Sigma-Aldrich

Methanol-d₄, anhydrous, ≥99.8 atom % D

611646

Sigma-Aldrich

Methanol-d₄, ≥99.8 atom % D, contains 0.05 % (v/v) TMS

151947

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Methanol-d₄, ≥99.8 atom % D

574732

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Acetonitrile solution, contains 0.1 % (v/v) trifluoroacetic acid, suitable for HPLC

574724

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Acetonitrile solution, contains 0.05 % (v/v) trifluoroacetic acid

612162

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576956

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Acetonitrile solution, contains 0.1 % (v/v) formic acid, suitable for HPLC

439029

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Methanol-d₄, ≥99.8 atom % D, contains 0.1 % (v/v) TMS

441384

Sigma-Aldrich

Methanol-d₄, ≥99.8 atom % D

422878

Sigma-Aldrich

Methanol-d₄, 99 atom % D

444758

Sigma-Aldrich

Methanol-d₄, "100%", 99.96 atom % D

417653

Sigma-Aldrich

Methanol-d₄, ≥99.8 atom % D, contains 1 % (v/v) TMS

W290017

Sigma-Aldrich

Phosphoric acid solution, 85 wt. % in H₂O, FCC, FG

343803

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Methanol-d₄, ≥99.8 atom % D, contains 0.03 % (v/v) TMS

685461

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679186

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699608

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Phosphoric acid solution, NMR reference standard, 85% in D₂O (99.9 atom % D), NMR tube size 3 mm × 8 in.

698822

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Phosphoric acid solution, NMR reference standard, 85% in D₂O (99.9 atom % D), NMR tube size 5 mm × 8 in.

PHR1320

Supelco

Residual Solvent - Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material

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675415

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01-0650

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Acetonitrile, ≥99.8%, suitable for HPLC

01-0590

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01-0600

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01-0620

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Acetonitrile, ≥99.8%, for residue analysis, JIS 300

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Acetonitrile, ≥99.8%, for residue analysis, JIS 1000

609781

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01-0623

Sigma-Aldrich

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466123

Sigma-Aldrich

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