MilliporeSigma
  • A novel ion-exclusion chromatography-mass spectrometry method to measure concentrations and cycling rates of carbohydrates and amino sugars in freshwaters.

A novel ion-exclusion chromatography-mass spectrometry method to measure concentrations and cycling rates of carbohydrates and amino sugars in freshwaters.

Journal of chromatography. A (2014-09-23)
Karel Horňák, Jakob Pernthaler
ABSTRACT

The concentrations of free neutral carbohydrates and amino sugars were determined in freshwater samples of distinct matrix complexity, including meso-, eu- and dystrophic lakes and ponds, using high-performance ion-exclusion chromatography (HPIEC) coupled to mass spectrometry (MS). In contrast to other methods, our approach allowed the quantification of free neutral carbohydrates and amino sugars at low nM concentrations without derivatization, de-salting or pre-concentration. New sample preparation procedures were applied prior to injection employing syringe and hollow fiber filtration. Analytes were separated on a strong cation exchange resin under 100% aqueous conditions using 0.1% formic acid as a mobile phase. To minimize background noise in MS, analytes were detected in a multiple reaction monitoring scan mode with double ion filtering. Detection limits of carbohydrates and amino sugars ranged between 0.2 and 2nM at a signal-to-noise ratio >5. Error ranged between 1 and 12% at 0.5-500nM levels. Using a stable isotope dilution approach, both the utilization and recycling of glucose in Lake Zurich was observed. In contrast, N-acetyl-glucosamine was equally rapidly consumed but there was no visible de novo production. The simple and rapid sample preparation makes our protocol suitable for routine analyses of organic compounds in freshwater samples. Application of stable isotope tracers along with accurate measures of carbohydrate and amino sugar concentrations enables novel insights into the compound in situ dynamics.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Formic acid, reagent grade, ≥95%
Sigma-Aldrich
D-(+)-Glucose, Hybri-Max, powder, BioReagent, suitable for hybridoma
Sigma-Aldrich
Sucrose, puriss., meets analytical specification of Ph. Eur., BP, NF
Supelco
Galactose, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Ammonia-14N, 99.99 atom % 14N
Galactose, European Pharmacopoeia (EP) Reference Standard
Supelco
Sucrose, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
D-(+)-Mannose, ≥99% (GC), wood
Supelco
Sucralose, Pharmaceutical Secondary Standard; Certified Reference Material
USP
Sucralose, United States Pharmacopeia (USP) Reference Standard
USP
Dextrose, United States Pharmacopeia (USP) Reference Standard
USP
Galactose, United States Pharmacopeia (USP) Reference Standard
USP
Sucrose, United States Pharmacopeia (USP) Reference Standard
Supelco
Sucralose, analytical standard
Sigma-Aldrich
L-(+)-Arabinose, 99%
Sucralose, European Pharmacopoeia (EP) Reference Standard
Xylose, European Pharmacopoeia (EP) Reference Standard
Sigma-Aldrich
Formic acid, ACS reagent, ≥96%
Sigma-Aldrich
Formic acid, puriss. p.a., ACS reagent, reag. Ph. Eur., ≥98%
Sigma-Aldrich
Formic acid, puriss., meets analytical specifications of DAC, FCC, 98.0-100%
Millipore
D-(+)-Mannose, ≥99%, suitable for microbiology
Sigma-Aldrich
D-(+)-Mannose, synthetic, ≥99% (GC)
Sucrose, European Pharmacopoeia (EP) Reference Standard
Sigma-Aldrich
N-Acetyl-D-glucosamine, suitable for cell culture, BioReagent
Sigma-Aldrich
D-(+)-Glucose, tested according to Ph. Eur.
Sigma-Aldrich
L-(+)-Arabinose, 98%
Sigma-Aldrich
D-(−)-Ribose, ≥98%
Sigma-Aldrich
D-(+)-Glucose, BioUltra, anhydrous, ≥99.5% (sum of enantiomers, HPLC)
Sigma-Aldrich
L-(+)-Arabinose, BioUltra, ≥99.5% (sum of enantiomers, HPLC)
Sigma-Aldrich
Divinylbenzene, technical grade, 80%