A glutathione S-transferase (GST, EC 2.5.1.18) inhibitor was isolated from the onion bulb by fractionation and purification using Sep-pak Vac C18 column, TLC and HPLC. Five partially purified onion bulb GSTs (GSTa and GSTb as minor GSTs, and GSTc, GSTd and GSTe as dominant GSTs) separated by DEAE column were used to detect the inhibitory substance in onion bulb extract. Among the three fraction...

This application note describes a fast UHPLC method for the determination of 20 ginsenosides. The developed method allows for the determination of 20 ginsenosides in less than 35 minutes. A binary high pressure gradient is used at a flow rate of 0.6 ml/min. By applying a Bluespher 100-2 C18 column in the dimension 150 x 2 mm ID, the total run time could be reduced to less than 41 minutes when a...

Generating chemical libraries in droplet form is vital to the adoption of microdroplet systems in high-throughput screening (HTS). This paper presents microfractionation in droplets (μFD), a method for generating heterogeneous droplet libraries using standard separation processes. In μFD, compounds eluting from a separation column are permanently encapsulated into droplets by a droplet generato...

A simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of Amlodipine besylate and Hydrochlorthiazide in tablet formulations. The chromatographic separation was achieved on a Shimadzu Symmetry C18 column (250 mm x 4.6mm, 5.0 μ particle size) using Methanol: Acetonitrile: 50mM Na2HPO4 pH7.0 (60:20:20v/v/v) with 1% triethylamine. Flow rate was 1ml/m...

New UPLC method was developed for determination of sitagliptin and metformin using Symmetry C18 column (100 mm × 2.1 mm, 2.2 μm) and isocratic elution (methanol 20%), pH (3.5) as a mobile phase. The ultraviolet detector was operated at 220 nm and the column temperature was 50°C. Linearity parameters were acceptable over the concentration ranges of 2-12 μgml(-1) and 5-35 μgml(-1) for sitagliptin...

To establish the method for qualitative and quantitative determination of gallic acid in Herba Gei. Gallic acid content is determined by HPLC with Diamonsil C18 column as the stationary phase, under the conditions of methanol-0.1% phosphoric acid in water (10:90) mobile phase, 271 nm detection wavelength, and 40°C column temperature. Peak area of gallic acid shows a good linearity with the inje...

A rapid separation of the ten nuclearly-encoded subunits of mitochondrial cytochrome c oxidase, and ten out of the eleven subunits of cytochrome bc1, was achieved using a short, 50 mm C18-reversed-phase column. The short column decreased the elution time 4-7 fold while maintaining the same resolution quality. Elution was similar to a previously published protocol, i.e., a water/acetonitrile elu...

A new simple isocratic RP-HPLC method was developed for the determination of milnacipran in bulk drug and in its capsules formulations. The mobile phase selected was methanol: acetonitrile:0.1% O-phosphoric acid in the ratio of 55:35:10%(v/v) and Zodiac C18 column with dimensions (250X4.6mm, 5μ)was used as stationary phase column temperature is ambient throughout the method. The flow rate and w...

Tocopherols extracted from plasma with methanol or from platelets with chloroform/methanol were injected in methanol on a reversed-phase (C18) "high-performance" liquid-chromatographic column and eluted with water/methanol (2/98, by vol) at a flow rate of 1.4 mL/min. A "high-performance" spectrophotofluorometer was used for detection. Analytical recoveries ranged from 89 to 106%. The response w...