Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add more filters










Database
Language
Publication year range
1.
J AOAC Int ; 107(4): 663-678, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38530970

ABSTRACT

BACKGROUND: Dietary supplements derived from botanicals are commonly consumed and investigated in biomedical studies for their potential health benefits. Accurate identification and quantification of key chemical constituents from botanical ingredients is necessary for consistent product preparations and reproducible research results. Manufacturers need quantitative reference materials of the chemical constituents of interest to verify the content of ingredients and products. The rigor and reproducibility of biomedical research is enhanced through thorough characterization of the interventions used in mechanistic, clinical, and safety investigations. Quantitative reference materials enable reliable product quality assessments and reproducible research results. OBJECTIVE: Solution-based certified reference material (CRM) mixes were developed as calibrants for phytochemicals in ginger and kava. The kava CRM contained yangonin, desmethoxyyangonin, dihydrokavain, DL-kavain, methysticin, dihydromethysticin, flavokawain A, flavokawain B, and flavokawain C. The ginger CRM contained 6-gingerol, 8-gingerol, 10-gingerol, 6-shogaol, 8-shogaol, and 10-shogaol. METHODS: Each phytochemical was sourced as an isolated compound and assigned a purity factor by a mass balance approach accounting for residual impurities. The solution standard mixes were formulated by gravimetric addition of each phytochemical incorporating the purity factor and diluting with acetonitrile to the target concentrations of 500 µg/mL for the gingerols and shogaols, 250 µg/mL for the kavalactones, and 25 µg/mL for the flavokawains. RESULTS: The concentration accuracy of each component in the solution mixes was analytically verified by ultra high performance liquid chromatography with ultraviolet detection (UHPLC-UV) assay comparison to an independently prepared calibration solution. Each component in the ginger and kava CRMs were within 5 and 7% of the target concentrations, respectively. CONCLUSION: Homogeneous kava and ginger phytochemical solution mixes were produced with accurate constituent concentrations and demonstrated good stability over 2 years. These solution mixes were launched as commercially available CRMs. HIGHLIGHTS: These mixes can be used as accurate concentration stock solutions to prepare calibrators and controls for botanical dietary supplement product testing and standardization.


Subject(s)
Fatty Alcohols , Kava , Phytochemicals , Reference Standards , Zingiber officinale , Zingiber officinale/chemistry , Kava/chemistry , Phytochemicals/analysis , Phytochemicals/standards , Phytochemicals/chemistry , Fatty Alcohols/analysis , Fatty Alcohols/chemistry , Catechols/analysis , Catechols/chemistry , Catechols/standards , Chromatography, High Pressure Liquid/methods , Dietary Supplements/analysis , Dietary Supplements/standards
2.
Bioanalysis ; 7(2): 207-20, 2015.
Article in English | MEDLINE | ID: mdl-25587837

ABSTRACT

BACKGROUND: In this study, we developed and validated a HPLC-MS/MS method capable of simultaneously determining levodopa, carbidopa, entacapone, tolcapone, 3-O-methyldopa and dopamine in human plasma. RESULTS & METHODOLOGY: Chromatographic separation was achieved using a C8 column with a mobile phase consisting of a gradient of water and acetonitrile:methanol (90:10 v/v), both containing 0.1% formic acid. The developed method was selective, sensitive (LD<7.0 ng ml(-1)), linear (r>0.99), precise (RSD<11.3%), accurate (RE<11.8%) and free of residual and matrix effects. The developed method was successfully applied in plasma patients with Parkinson's disease using Stalevo®. CONCLUSION: The new method can be used for the clinical monitoring of these substances and applied to adjustments in drug dosages.


Subject(s)
Benzophenones/blood , Blood Chemical Analysis/methods , Carbidopa/blood , Catechols/blood , Chromatography, High Pressure Liquid , Dihydroxyphenylalanine/analogs & derivatives , Dopamine/blood , Levodopa/blood , Nitriles/blood , Nitrophenols/blood , Tandem Mass Spectrometry , Benzophenones/standards , Carbidopa/standards , Catechols/standards , Chromatography, High Pressure Liquid/standards , Dihydroxyphenylalanine/blood , Dihydroxyphenylalanine/standards , Dopamine/standards , Humans , Levodopa/standards , Nitriles/standards , Nitrophenols/standards , Quality Control , Reproducibility of Results , Tandem Mass Spectrometry/standards , Tolcapone , Tyrosine/analogs & derivatives
SELECTION OF CITATIONS
SEARCH DETAIL
...