Wyniki wyszukiwania - BazTech

1

Liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the determination of Vildagliptin in rat plasma

Sakthimanigandan K., Ganesh M., Kanthikiran V., Sivakumar T., Jang H.

Acta Chromatographica

|

2015

|

Vol. 27, no. 2

295--307

EN

A new sensitive and validated liquid chromatography electro spray ion-tandem mass spectrometry (HPLC-ESI-MS/MS) method for the quantification of Vildagliptin (VG) in rat plasma has been developed and validated using repaglinide (RG) as an internal standard (IS). The analytes were extracted by liquid-liquid extraction using ethyl acetate. Elution of the VG and IS was achieved on a reverse phase Betasil (C18 50 mm 4.6 mm ID, 5 μ) column with an isocratic mobile phase composed of acetonitrile: 2 mM ammonium acetate (90:10 v/v). The analytes monitored in the Multiple Reaction Monitoring (MRM) mode were m/z 304.2→154.0 and 453.3→230.3 for VG and RG, respectively. The calibration curve was linear in the range of 1.57–501.21 ng/mL for VG with lower limit of quantification 1.57 ng/mL. The intra run and inter run precision values are within 11.70% for VG at LOQ level.

2

Validated HPLC method for analysis of oxaprozin in a formulation

Ganesh M., Thangabalan B., Patil R., Thakur D., Saravana Kumar A., Vinoba M., Ganguly S., Sivakumar T.

Acta Chromatographica

|

2008

|

Vol. 20, no. 2

165-173

EN

A rapid, simple and validated reversed-phase high-performance liquid chromatographic method has been developed for analysis of oxaprozin in pharmaceutical dosage forms. Oxaprozin was separated on an ODS analytical column with a 45:55 (v/v) mixture of acetonitrile and triethanolamine solution (5 mM, pH 3.5 š 0.05, adjusted by addition of 85% phosphoric acid) as mobile phase at a flow rate of 2.0 mL min-1. The effluent was monitored by UV detection at 254 nm. Calibration plots were linear in the range 160 to 240 µg mL-1 and the LOD and LOQ were 14.26 and 41.21 µg mL-1, respectively. The high recovery and low relative standard deviation confirm the suitability of the method for routine QC determination of oxaprozin in tablets.

3

Computer-assisted optimization of liquid-liquid extraction for HPLC analysis of domperidone and pantoprazole in human plasma

Sivakumar T., Manavalan R., Valliappan K.

Acta Chromatographica

|

2008

|

Vol. 20, no. 4

549-562

EN

This paper deals with optimization of a liquid-liquid extraction procedure for simultaneous HPLC analysis of domperidone and pantoprazole in human plasma. Central composite design and Derringer’s desirability function were used to optimize the concentration of KOH and the volume of ethyl acetate as the main factors affecting the liquid-liquid extraction procedure. After extraction, the analytes were separated quantitatively on a C 18 column with 10 mM pH 7.0 phosphate buffer-methanol-acetonitrile 48.46:20:31.54 ( υ / υ ) as mobile phase at a flow rate of 1.20 mL min -1 and with UV detection at 285 nm. It was concluded that extraction recovery of both the analytes was affected by KOH concentration and that recovery of pantoprazole was affected by ethyl acetate (extraction solvent) volume. Extraction recovery under optimum extraction conditions was 93.52% for domperidone and 92.72% for pantoprazole. The optimized extraction method was validated. Linearity was established for six levels in the ranges 10–1000 ng mL -1 for pantoprazole and 15–1000 ng mL -1 for domperidone. The lower limit of quantitation (LLOQ) and detection (LOD) were estimated as 9.84 and 5.91 ng mL -1 , respectively, for pantoprazole and 14.56 and 8.79 ng mL -1 for domperidone. The optimized method was linear, specific, accurate, and precise; the high recovery (>92%) and low relative standard deviation (<2.5%) enable reliable quantification of these analytes in spiked human plasma.

4

Global optimization using Derringer's desirability function: enantioselective determination of ketoprofen in formulations and in biological matrices

Sivakumar T., Manavalan R., Valliappan K.

Acta Chromatographica

|

2007

|

No. 19

29-47

EN

A reversed-phase high-performance liquid chromatographic method for separation of the enantiomers of ketoprofen in formulations and in plas-ma matrices has been developed and optimized. A central composite design was used to develop response models and Derringer’s desirability function was then used for simultaneous optimization of chiral resolution and analysis time. This procedure enabled discovery of two separate sets of opti-mum conditions for analysis of quality-control samples and plasma samples within the experimental domain. The optimum conditions predicted for quality-control samples were acetonitrile–dipotassium hydrogen phosphate buffer (10 mΜ, pH 6.5)–triethylamine 56:44:0.05 (/ν) as νmobile phase and 1.13 mL min-1 as flow rate. Use of these conditions enabled baseline separation of the enantiomers of ketoprofen in approximately 4.2 min, which is quicker than the previously optimized method. The method was suitable for routine analysis of the enantiomers of ketoprofen in a commercial pharmaceutical preparation and in plasma samples.

5

Development and validation of a reversed-phase HPLC method for simultaneous determination of domperidone and pantoprazole in pharmaceutical dosage forms

Sivakumar T., Manavalan R., Valliappan K.

Acta Chromatographica

|

2007

|

No. 18

130-142

EN

A simple reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been developed and validated for simultaneous determination of domperidone and pantoprazole in capsules. The compounds were separated on an ODS analytical column with a mixture of methanol, acetonitrile, and triethylamine solution (10 mM, pH 7.0 ± 0.05 adjusted with 85% phosphoric acid) in the ratio 20:33:47 (v/v) as mobile phase at a flow rate of 1.0 mL min-1. UV detection was performed at 285 nm. The method was validated for accuracy, precision, specificity, linearity, and sensitivity. The developed and validated method was successfully used for quantitative analysis of Pantop-D capsules. Total chromatographic analysis time per sample was approximately 10 min with pantoprazole, acetophenone (internal standard), and domperidone eluting with retention times of 4.34, 5.52, and 9.46 min, respectively. Validation studies revealed the method is specific, rapid, reliable, and reproducible. Calibration plots were linear over the concentration ranges 0.5–5 µg mL-1 and 1–10 žg mL-1 for domperidone and pantoprazole, respectively. The LODs were 15.3 and 3.0 ng mL-1 and the LOQs were 51.0 and 10.1 ng mL-1 for domperidone and pantoprazole, respectively. The high recovery and low relative standard deviation confirm the suitability of the method for determination of domperidone and pantoprazole in capsules.