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PubMed · 7628094

Spectrophotometric determination of ascorbic acid and dehydroascorbic acid.

T Moeslinger·M Brunner·I Volf·P G Spieckermann
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Abstract

We present a method for measuring ascorbic acid in methanol/trichloroacetic acid extracts prepared from human plasma after enzymatic oxidation of ascorbic acid to dehydroascorbic acid by ascorbate oxidase. Samples were assayed by spectrophotometrically monitoring the kinetics of the concentration-dependent absorbance changes of dehydroascorbic acid with phosphate-citrate-methanol buffers. Ascorbic acid was determined as the difference between dehydroascorbic acid and total ascorbic acid content. The detection limit was < 0.5 mumol/L. The calibration curve was linear (r > 0.995) over the range 0-1000 mumol/L. Analytical recovery of ascorbic acid added to plasma was 93-105%. The between-day variance was < 7%. Comparison of the spectrophotometric determination (y) with a chromatographic procedure (x) gave y = 1.02x - 0.653 (Sylx = 3.61) over the range of physiologically relevant concentrations. Total analysis time is < 10 min per sample and allows the simultaneous analysis of multiple samples.

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Ascorbate OxidaseAscorbic AcidBuffersChromatography, High Pressure LiquidCitratesCitric AcidDehydroascorbic AcidHumansKineticsMethanolOxidation-ReductionPhosphatesSensitivity and SpecificitySpectrophotometryThermodynamicsTrichloroacetic AcidJournal Article

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T Moeslinger, M Brunner, I Volf, P G Spieckermann. 1995. Spectrophotometric determination of ascorbic acid and dehydroascorbic acid.. https://pubmed.ncbi.nlm.nih.gov/7628094/

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