Zafirlukast (ZAF) is a leukotriene receptor antagonist used in the treatment of chronic asthma. In this study, a simple and sensitive reversed-phase, high-performance liquid chromatographic method was developed for the determination of ZAF in pharmaceutical formulations and human plasma. Piribedil was used as an internal standard. Analysis was carried out on a Nucleosil C18 100 A (150 mm x 4.6 ...

Background During a series of visits to pharmaceutical and fine chemical plants, a SpotView system was used to develop preliminary calibrations for various APIs, excipients, and cleaning materials. The calibrations were based on sets of spectra collected from standard coupons. In the first case, the calibration was challenged with a set of samples that had been independently prepared, some spik...

background and objectives: analytical methods for volatile organic compounds (vocs) in different samples need extraction of compounds, by applying hazardous solvents. solid phase micro-extraction (spme) is a solvent-free equilibrium extraction method, in which proper calibration can allow quantitative determinations of vocs at a very good sensitivity without the use of any organic solvent. vocs...

Accurate and detailed spatial soil information about within-field variability is essential for variable-rate applications of farm resources. Soil total nitrogen (TN) and total carbon (TC) are important fertility parameters that can be measured with on-line (mobile) visible and near infrared (vis-NIR) spectroscopy. This study compares the performance of local farm scale calibrations with those b...

In modern road surveys, hanging power cables are among the most commonly-found geometric features. These cables are catenary curves that are conventionally modelled with three parameters in 2D Cartesian space. With the advent and popularity of the mobile mapping system (MMS), the 3D point clouds of hanging power cables can be captured within a short period of time. These point clouds, similarly...

Real-time PCR (qPCR) is the principal technique for the quantification of pathogen biomass in host tissue, yet no generic methods exist for the determination of the limit of quantification (LOQ) and the limit of detection (LOD) in qPCR. We suggest using the Youden index in the context of the receiver operating characteristic (ROC) curve analysis for this purpose. The LOQ was defined as the amou...

In communities which consume rice as main food, importance of risk assessment forcontaminants is always taken into consideration by health authorities. The present study isan attempt for monitoring of 56 pesticides from different chemical groups in rice samplescollected from local markets in Tehran and estimation of daily intake of interested pesticidesthrough this monitoring. A valid method ba...

A high-performance reversed-phase liquid chromatographic method for quantification of metoprolol tartrate (MT) in human plasma is presented. A C18 column was used with acetonitrile–water–triethylamine 18:81:1 (v/v) as mobile phase and pinacidil monohydrate as internal standard (IS). UV detection was at 275 nm and MT and the IS were detected at retention times of 1.5 and 2.6 min, respectively. T...

If, in addition to the usual luminosity correction described by the light curve slope parameter b, we introduce a color correction parameter R, then an extraordinarily good fit is realized for all the 29 distant Type Ia supernovae of the recent Calán/Tololo supernova survey. The reduced χ2 found is much lower than can be expected. All of the intrinsic dispersion is thereby removed from the data...