Agilent 7000c triple quadrupole gc ms system

Approximately 2 mg oligosaccharide fraction was hydrolyzed using 4 ml of 2 M trifluoroacetic acid at 110°C for 2 h. The hydrolysate sample was dried, dissolved in water, and then reduced with NaBH₄. The samples were acetylated with 0.5 ml pyridine-acetic anhydride at a ratio of 1 : 1 v/v and 90°C for 1.5 h. In addition, the rhamnose, fucose, arabinose, xylose, mannose, glucose, galactose, D-(+)-chiro-inositol, and myo-inositol of nine monosaccharides were used as standards to quantify the monosaccharide content. The mixture of the standards was reduced and acetylated by using the same method. The resulting alditol acetates were examined by the Agilent 7000C Triple Quadrupole GC/MS System (Agilent Technologies Inc., USA). Samples were analyzed on a HP-5-fused silica column (J&W Scientific Co., USA). The initial oven temperature was held at 60°C for 2 min, raised to 190°C for 1 min at 15°C/min, raised to 240°C for 3 min at 5°C/min, and then increased to 300°C for 5 min at 10°C/min. GC-MS data were analyzed using Agilent Software (Agilent Mass Hunter Qualitative Analysis B.07.00).

A fasting blood sample was sent to the Dept. of Biochemistry, Hammersmith Hospital on each study visit for cholesterol (total, HDL, LDL) and triglyceride measurement. An aliquot of urine was also sent to the Dept. of Biochemistry for urinary urea quantification. Glucose analysis was performed in the Dept. of Biochemistry, Hammersmith Hospital using a ci8200 analyser enzymatic method (Abbott, Abbott Park, IL, USA). Insulin analysis was performed in-house using a human insulin RIA kit (Millipore Corporation, Billerica, MA, USA) according to manufacturer’s guidelines with 50 µL serum. PYY and GLP-1 were measured using previously established in-house specific and sensitive RIA [18 (link),19 (link)]. Acetate, propionate and butyrate were measured at Dept. of Cancer and Surgery using an Agilent 7000C Triple Quadrupole GC/MS System (Agilent, Santa Clara, CA, USA) according to a previously published method [20 (link)]. NEFA were measured using a commercial kit (FA115 NEFA kit; Randox, London, UK) and were measured using an ILAB 650 Clinical Chemistry Analyser (Instrumentation Laboratory, Birchwood, Warrington, UK).