A simple, rapid, precise and accurate HPLC – UV procedure has been developed to determine benzaldehyde, the toxic oxidation product of the widely used preservative and Co – solvent, benzyl alcohol, in injectable formulations. Benzaldehyde as a main potential impurity of benzyl alcohol may cause many toxic effects such as neurotoxicity, hypersensitivity in human and fatal toxic syndrome in prema...

The aim of current investigation was the validation of HPLC method with UV-detection for identification and determination of Yohimbine by using column Spherisorb ODS RP C18 (250 mm x 4.6 mm x 5 μm), temperature: 25 oC, mobile phase: methanol : acetonitrile : water = 70 : 20 : 10 v/v, flow rate: 2 ml/min., UV-detection: λ = 270 nm. HPLC method was validated in accordance of linearity, limit of d...

This study reports a novel detection method of Thermal Lens Microscopy (TLM), in which the excitation of analytes is manipulated by Optical Near-Field (ONF) generated on nanostructures. Owning to the property of apparent higher energy than incident photons, herein the ONF allows the electronic excitation of molecules even though the energy of incident light is lower than absorption energy of mo...

We present a compact bichromatic imaging system, located outside of the vacuum chamber trapped ion apparatus that collects fluorescence 230.6 and 369.5 nm photons simultaneously on shared electron-multiplying charge-coupled device (EMCCD) camera. The system contains two lens doublets, consisting sphere an asphere. They provide numerical aperture 0.45 0.40 at nm, respectively, enable spatially r...

Liquid chromatography (LC) with cavity ring-down spectroscopy (CRDS) detection, using flow cuvettes (put under normal incidence inside the ring-down cavity), is demonstrated. Fresnel reflections are maintained within the capture range of a stable cavity of 4 cm length. This method circumvents the need for specific Brewster's angles and possible mirror degradation is avoided. The flow cuvettes a...

The applicability of Supercritical Fluid Chromatography (SFC) can be substantially enhanced by coupling SFC to Mass Spectrometric detection (MSD). In this Technical Overview, two instrument configurations are described that can be used to connect the Agilent 1260 Infinity Analytical SFC to a mass spectrometer either using an atmospheric pressure chemical ionization (APCI) or an electrospray (ES...

A validated ultrahigh-performance liquid chromatography method using 1.7 μm core-shell particles is presented for the identification and quantification of β-carotene (BC) and related cleavage products (CPs) in primary cell culture media. Besides BC, apo-4'-, apo-8'-, apo-10'-, and apo-12'-carotenals, as well as 5,6-epoxy-β-carotene, were selected as target analytes. Detection was performed via ...

extraction of trace amounts of toxic heavy metals from complicated environmental matrixes is a  challenging task. the aim of this investigation is the comparison of the extraction efficiencies and other related experimental variables ( chemicals, effect of ph, potential interfering ions) on the determination of inorganic lead ( ) which is present in waste water of dye industries. compared techn...

background: in general, measurements of solar ultraviolet (uv) radiation are related to horizontal surfaces. while the hu­mans walking and standing outdoors expose to the natural solar uv radiation, their eyes, cheeks, extremities, trunks, or many other anatomical sites are close to vertical plane and random orient to different directions. in this study, we character­ized the diurnal variations...

Monomeric and oligomeric proanthocyanidins present in a range of plant-derived foods and beverages were separated by degree of polymerization and identified using a modified normal-phase high-performance liquid chromatography (HPLC) method coupled with on-line mass spectrometry (MS) analysis using an atmospheric pressure ionization electrospray chamber. In addition, ultraviolet (UV) and fluores...