Development and Validation of a Liquid Chromatographic Method for the Determination of Leflunomide: Application to <i>in vitro</i> Drug Metal Interactions

High-speed countercurrent chromatography (HSCCC) combined with biphasic chiral recognition was successfully applied to the resolution of phenylsuccinic acid enantiomers. D-Isobutyl tartrate and hydroxypropyl-β-cyclodextrin were employed as lipophilic and hydrophilic selectors dissolved in the organic stationary phase and aqueous mobile phase, respectively. The two-phase solvent system was made up of n-hexane/methyl tert-butyl ether/water (0.5:1.5:2, v/v/v). Impacts of the type and concentration of chiral selectors, the pH value of the aqueous phase solution as well as the temperature on the separation efficiency were investigated. By means of preparative HSCCC, pure enantiomer was obtained by separating 810 mg of racemate with a purity >99.5% and a recovery rate between 82 and 85%. The experimental results indicate that biphasic recognition HSCCC provide a promising means for efficient separation of racemates.

show abstract

“…The quantification of PSA enantiomers was performed by HPLC using a UV detector set at 254 nm. The column was an Inertsil ODS‐3 (4.6 × 250 mm).…”

Section: Methodsmentioning

confidence: 99%

Separation of phenylsuccinic acid enantiomers using biphasic chiral recognition high‐speed countercurrent chromatography

Sun

Tang

Yang

et al. 2014

J of Separation Science

View full text Add to dashboard Cite

show abstract

“…Previously, numerous methods were developed and validated for leflunomide determination and quantification in IP, dosage formulations [12,13] and serum [14][15][16]. We have reported determination of lefunomide by RP-HPLC [17]. A method of reversed phase chromatography has been reported to separate seven NSAIDs i.e.…”

Section: Introductionmentioning

confidence: 99%

Development of Liquid Chromatography? UV Method for Simultaneous Determination of Leflunomide and NSAIDs in API and Pharmaceutical Formulations: It?s Application to In vitro Interaction Studies

Sultana¹,

Arayne²

2012

Med Chem (Los Angeles)

Self Cite

View full text Add to dashboard Cite

An efficient analytical method for the simultaneous determination of leflunomide and non steroidal anti-inflammatory drugs in API and formulations by LC-UV has been developed. The analytes were separated on Purospher Star, C 18 (5 µm, 250×4.6 mm) column at ambient temperature with methanol: water (80:20, v/v, pH at 2.7) at flow rate of 1.5 mL min -1 . Experiment was conducted in two phases. Leflunomide was separated with flurbiprofen and ibuprofen (phase-I) and diclofenac sodium and mefenamic acid (phase II). Calibration curves were linear over the range 0.625-5 µg mL -1 in both phases for leflunomide while for flurbiprofen, ibuprofen, diclofenac sodium, mefenamic acid linearity were achieved in the range of 0.625-5, 11.25-90, 1.56-50 and 0.78-25 µg mL -1 , respectively with r 2 >0.9998. Intraday variation was <1.2 and <1.4 %, while in inter-day ranged between 0.042-1.45% and 0.08-1.27% in phase-I and II, respectively. Mean recovery values for intra-day ranged from 99.04-100.4% and 98.48-100.2% and for inter-day were between 98.54-100.29% and 98.85-100.54% in phase-I and II, respectively. The LLOD of leflunomide was 13 ng mL -1 , while LLOQ was 39ng mL -1 , respectively. LLOD and LLOQ for flurbiprofen, ibuprofen, diclofenac sodium and mefenamic acid were 6.9, 296, 71 and 1.2 ng mL -1 and 21, 897, 214.3 and 3.676 ng mL -1 , respectively. Present study showed that nanogram quantities of all the compounds can be estimated accurately. The newly established method was successfully applied to study in vitro interactions between leflunomide and NSAIDs.

show abstract

Determination of sulfonylurea herbicides in soil by ionic liquid-based ultrasonic-assisted extraction high-performance liquid chromatography

et al. 2014

View full text Add to dashboard Cite

A high-performance liquid chromatography method for determination of sulfonylurea herbicides in soil has been developed. Prior to the determination, sample preparation was performed by ionic liquid-based ultrasonic-assisted extraction (IL-based UAE). Dried soil powder was mixed with a room temperature ionic liquid, [C 6 MIM][BF 4 ], to form a suspension, and then ultrasonic extraction was performed in a water bath at ambient temperature. The chromatographic separation was performed using a C18 chromatographic column with gradient elution mode. The method was validated by evaluating the repeatability, linearity, precision, and applicability. The limits of detection ranged from 7.7 ng g À1 to 11.3 ng g À1 and the limits of quantification were between 25.6 ng g À1 and 37.6 ng g À1 . The calibration curves showed a good linear relationship (r > 0.9990) in the concentration ranges of 50.0-25 000 ng g À1 for nicosulfuron and 50.0-5000 ng g À1 for metsulfuron-methyl, bensulfuron-methyl and pyrazosulfuron-ethyl. The recoveries ranged from 81.1 to 100.1% with relative standard deviations lower than 7.44%. The IL-based UAE is free of volatile organic solvent, and consumes less sample, time and solvent, compared with regular ultrasonic and Soxhlet extractions. There was no obvious difference in the extraction recoveries of sulfonylurea herbicides obtained by the three methods.

show abstract

Development and Validation of a Liquid Chromatographic Method for the Determination of Leflunomide: Application to in vitro Drug Metal Interactions

Cited by 5 publications

References 26 publications

Separation of phenylsuccinic acid enantiomers using biphasic chiral recognition high‐speed countercurrent chromatography

Separation of phenylsuccinic acid enantiomers using biphasic chiral recognition high‐speed countercurrent chromatography

Development of Liquid Chromatography? UV Method for Simultaneous Determination of Leflunomide and NSAIDs in API and Pharmaceutical Formulations: It?s Application to In vitro Interaction Studies

Determination of sulfonylurea herbicides in soil by ionic liquid-based ultrasonic-assisted extraction high-performance liquid chromatography

Contact Info

Product

Resources

About