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High Performance Liquid Chromatographic (high + performance_liquid_chromatographic)
Terms modified by High Performance Liquid Chromatographic Selected AbstractsHigh performance liquid chromatographic,mass spectrometric assay for the quantitation of BMS-204352 in dog K3EDTA plasmaBIOMEDICAL CHROMATOGRAPHY, Issue 3 2002Ming Yao A high performance liquid chromatographic-mass spectrometric (LC/MS) assay was developed and validated for the determination of BMS-204352 in dog K3EDTA plasma. A 0.5,mL aliquot of control plasma was spiked with BMS-204352 and internal standard (IS) and buffered with 1,mL of 5,mM ammonium acetate. The mixture was then extracted with 3,mL of toluene. After separation and evaporation of the organic phase to dryness using nitrogen at 40°C, the residue was reconstituted in the mobile phase and 25,µL of the sample were injected onto a Hypersil C18 column (2,×,50,mm; 3,µm) at a flow rate of 0.5,mL/min. The mobile phase was consisted of two solvent mixtures (A and B). Solvent A was composed of 5,mM ammonium acetate and 0.1% triethylamine in 75:25 v/v water:methanol, pH adjusted to 5.5 with glacial acetic acid, and solvent B was 5,mM ammonium acetate in methanol. A linear gradient system was used to elute the analytes. The mass spectrometer was programmed to admit the de-protonated molecules at m/z 352.7 (IS) and m/z 357.9 (BMS-204352). Standard curves of BMS-204352 were linear (r2,,,0.998) over the concentration range of 0.5,1000,ng/mL. The mean predicted quality control (QC) concentrations deviated less than 5.1% from the corresponding nominal values (ie 4, 80, 400 and 2000,ng/mL); the within- and between-assay precision of the assay were within 5.5% relative standard deviation. Stability of BMS-204352 was confirmed after at least three freeze/thaw cycles and BMS-204532 was stable in dog plasma when stored frozen at or below ,20°C for at least 16 weeks in spiked QC samples and for at least 4 1/2 weeks for in vivo study samples. BMS-204352 and IS were stable in the injection solvent at room temperature for at least 24,h. The assay was applied to delineate the pharmacokinetic disposition of BMS-204352 in dogs following a single intravenous dose administration. In conclusion, the assay is accurate, precise, specific, sensitive and reproducible for the pharmacokinetic analysis of BMS-204532 in dog plasma. Copyright © 2002 John Wiley & Sons, Ltd. [source] Fingerprint chromatogram analysis of Pseudostellaria heterophylla (Miq.) Pax root by high performance liquid chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2006Chao Han Abstract A simple and reliable high performance liquid chromatographic (HPLC) method has been developed and validated for the fingerprinting of extracts from the root of Pseudostellaria heterophylla (Miq.) Pax. HPLC with gradient elution was performed on an authentic reference standard of powdered P. heterophylla (Miq.) Pax root and 11 plant samples of the root were collected from different geographic locations. The HPLC chromatograms have been standardized through the selection and identification of reference peaks and the normalization of retention times and peak intensities of all the common peaks. The standardized HPLC fingerprints show high stability and reproducibility, and thus can be used effectively for the screening analysis or quality assessment of the root or its derived products. Similarity index calculations based on cosine angle values or correlation methods have been performed on the HPLC fingerprints. As a group, the fingerprints of the P. heterophylla (Miq.) Pax samples studied are highly correlated with closely similar fingerprints. Within the group, the samples can be further divided into subgroups based on hierarchical clustering analysis (HCA). Sample grouping based on HCA coincides nicely with those based on the geographical origins of the samples. The HPLC fingerprinting techniques thus have high potential in authentication or source-tracing types of applications. [source] A simple and rapid high-performance liquid chromatography method for determination of alendronate sodium in beagle dog plasma with application to preclinical pharmacokinetic studyBIOMEDICAL CHROMATOGRAPHY, Issue 2 2010Jian Meng Abstract A simple and rapid high performance liquid chromatographic (HPLC) method for quantifying alendronate in beagle dog plasma was developed, validated and applied to a pharmacokinetic study. The sample preparation involved coprecipitation with CaCl2 and derivatization with o -phthalaldehyde. Chromatographic separation was achieved on a DiamonsilÔ C18 (250 × 4.6,mm, 5,µm) using acetonitrile,0.4% EDTA-Na2 (16:84, v/v) containing 0.034% of NaOH as mobile phase. The fluorimetric detector was operated at 339,nm (excitation) and 447 nm (emission). The linearity over the concentration range of 5.00,600,ng/mL for alendronate was obtained and the lower limit of quantification was 5.00,ng/mL. For each level of quality control samples, inter-day and intra-day precisions were less than 8.52 and 7.42% and accuracies were less than 9.07%. The assay was applied to the analysis of samples from a pharmacokinetic study. Following the oral administration of 70,mg alendronate sodium to beagle dogs, the maximum plasma concentration (Cmax) and elimination half-life were 152,±,27.3 and 1.75,± 0.267,h, respectively. The method was demonstrated to be highly feasible and reproducible for pharmacokinetic studies. Copyright © 2009 John Wiley & Sons, Ltd. [source] Determination of terbinafine hydrochloride in cat hair by two chromatographic methodsBIOMEDICAL CHROMATOGRAPHY, Issue 8 2001Jernej Kuz Terbinafine hydrochloride (terbHCl) concentration on the site of infection with Microsporum canis is a very important indicator of drug effectiveness. Several chromatographic methods exist that can be used for the determination of terbHCl concentration in biological samples. A high performance liquid chromatographic (HPLC) method and a gas chromatographic (GC) method have been compared and critically evaluated for the determination of a terbHCl levels in cat hair. The sensitivity and the linearity of the previously developed HPLC method were 0.25,ng/mL and 0.25,3000,ng/mL, respectively. The limit of quantification (LOQ) was 0.01,µg/g of terbHCl in cat hair, and reproducibility of 96.6% and recovery of 93.8% were achieved using appropriate sample pre-treatment and optimal chromatographic conditions. The sensitivity of the GC method, 25,ng/mL (LOQ 625 ppb), was much lower than that of the HPLC method. The GC method still enables determination of terbHCl in a range of concentrations in cat hair. The reproducibility of terbHCl for the cat hair samples was 95.3% and the recovery was only 70.0%. Both methods can be used for the evaluation of drug effectiveness in cats and both of them require only basic chromatographic equipment that can be found in most analytical laboratories. Copyright © 2001 John Wiley & Sons, Ltd. [source] Simultaneous Determination of Epinephrine, Noradrenaline and Dopamine in Human Serum Samples by High Performance Liquid Chromatography with Chemiluminescence DetectionCHINESE JOURNAL OF CHEMISTRY, Issue 7 2007Fu-Nan Chen Abstract A simple, rapid and accurate high performance liquid chromatographic (HPLC) technique coupled with chemiluminescence (CL) detection was developed for the simultaneous determination of epinephrine (E), noradrenaline (NA) and dopamine (DA). It was based on the analyte enhancement effect on the CL reaction between luminol and potassium ferricyanide. The effects of various parameters, such as potassium ferricyanide concentration, luminol concentration, pH value and component of the mobile phase on chromatographic behaviors of the analytes (E, NA and DA) were investigated. The separation was carried out on C18 column using the mobile phase of 0.01 mol/L potassium hydrogen phthalate solution and methanol (92:8, V/V). Under the optimum conditions, E, NA and DA showed good linear relationships in the range of 1×10,8,5×10,6, 5.0×10,9,1.0×10,6 and 5.0×10,9,1.0×10,6 g/mL respectively. The detection limits for E, NA and DA were 4.0×10,9, 1.0×10,9 and 8.0×10,10 g/mL. The proposed method has been applied successfully to the analysis of E, NA and DA in human serum samples. [source] | ||||||||||