A new isocratic HPLC method is optimized and validated for simultaneous determination of Vildagliptin (VLD), Pioglitazone Hydrochloride (PIO) and Glimepiride (GLIM) in Bulk and tablets (Gliptus ® and Amaglust ® tablets). The chromatographic separation was achieved on a reversed-phase analytical column [Hypersilgold ® C18 (10μm, 150 x 4.6 mm) column] at ambient temperature. The separation was ac...

Purpose: To study the influence of different sulfur fumigation time and dosage on the chemical constituents of Baizhi (Angelicae dahurica Radix). Methods: The relationship of chemical constituents in Baizhi with different sulfur fumigation time and dosages was evaluated by high performance liquid chromatography (HPLC) fingerprint and chemometrics methods, including similarity analysis (SA), hie...

Aflatoxin B1 (AFB1) was detected in serum samples of healthy Japanese males by radioimmunoassay and high-performance liquid chromatography. Blood samples were obtained from 20 subjects after fasting and from 80 subjects after lunch. The subjects ranged in age from 20 to 63 years of age. Measurement of AFB1 in the samples was performed by radioimmunoassay and was confirmed by high-performance li...

describes the isolation, properties and structure of 1, which is related to dianemycin (2).X) The fermentation of S. hygroscopicus sp. ATCC 53626 and isolation of crude 1-Na as a hexane soluble oil (150g) was carried out as described elsewhere.2) This material was purified by HPLC on a Waters ^Bondapak C18 column using methanol water (90: 10), followed by HPLC on a silica gel column using methy...

Positive-ion thermospray liquid chromatography-mass spectrometry (TSP-LC-MS) is used to detect organic acids via the direct injection of untreated urine from newborns and infants. Two methods are reported for the separation of organic acids. The separation of urinary organic acids is effected in either an acidic, pH 2.5 sulfuric acid, or a non-acidic, 0.05 M ammonium acetate, pH 6.8, mobile pha...

Both non-oxidized and oxidized mAb were diluted (1 to 9 ratio) with labeling buffer and incubated for multiple time points. The samples were then quenched with 4M guanidine, 200 mM citric acid (pH 2.7) at 0.5 °C and subject to online pepsin digest at 8 °C for three minutes at 50 μL/min flow rate in a fully automated manner using H/D-X PAL (LEAP Technologies). The digested peptides were injected...

The availability of deuterium-labeled nicotinic acid makes stable isotope dilution mass spectromerty (MS) coupled with liquid chromatography (LC) an attractive option for the determination of the water-soluble B-vitamin niacin in food samples. A method was developed based on acid digestion, solid-phase extraction with a strong cation exchange column, and reversed-phase chromatography with a C18...

Modified quantitative structure retention relationships (QSRRs) are proposed and applied to describe two retention data sets: A set of 94 metabolites studied by a hydrophilic interaction chromatography system under organic content gradient conditions and a set of tryptophan and its major metabolites analyzed by a reversed-phase chromatographic system under isocratic as well as pH and/or simulta...

Cyclaradine is a novel carbocyclic nucleoside with good activity against the viruses of the herpes group. To facilitate pharmacokinetic studies on cyclaradine, an automated column-switching high-performance liquid chromatographic (HPLC) method was developed for the determination of cyclaradine in serum. Deproteinized serum containing cyclaradine was directed to an on-line extraction column whic...

Hydrolyzed gallic acid in Potentilla chinensis Ser. was determined by HPLC using Potentilla chinensis Ser. as a model drug with chromatographic conditions as follows: Hypersil C18 column (250 mm × 4.6 mm, 5 μm); mobile phase methanol-0.05% aqueous solution of phosphoric acid (10:90); volume flow 1.0 mL/min; detection wavelength 271 nm; column temperature 25°C; and injection volume 20 μL. Inject...