Search results for " Analytic"

Fast UPLC/PDA determination of squalene in Sicilian P.D.O. pistachio from Bronte: Optimization of oil extraction method and analytical characterizati…

2017

Abstract A fast reversed-phase UPLC method was developed for squalene determination in Sicilian pistachio samples that entry in the European register of the products with P.D.O. In the present study the SPE procedure was optimized for the squalene extraction prior to the UPLC/PDA analysis. The precision of the full analytical procedure was satisfactory and the mean recoveries were 92.8 ± 0.3% and 96.6 ± 0.1% for 25 and 50 mg L−1 level of addition, respectively. Selected chromatographic conditions allowed a very fast squalene determination; in fact it was well separated in ∼0.54 min with good resolution. Squalene was detected in all the pistachio samples analyzed and the levels ranged from 5…

Comparison of Two Solid-Phase Extraction (SPE) Methods for the Identification and Quantification of Porcine Retinal Protein Markers by LC-MS/MS

2018

Proper sample preparation protocols represent a critical step for liquid chromatography-mass spectrometry (LC-MS)-based proteomic study designs and influence the speed, performance and automation of high-throughput data acquisition. The main objective of this study was to compare two commercial solid-phase extraction (SPE)-based sample preparation protocols (comprising SOLA&micro

Validated HPLC-UV detection method for the simultaneous determination of ceftolozane and tazobactam in human plasma

2018

Aim: A simple, rapid, economical and sensitive HPLC-UV method was developed for the simultaneous quantification of ceftolozane and tazobactam in plasma samples. Methodology: After deproteinization followed by a liquid–liquid back-extraction, the compounds were separated on a C18 column (150 mm × 4.6 mm, 5 μm) with UV-visible detection at 220 nm. The mobile phase consisted of acetonitrile and potassium dihydrogenphosphate buffer at pH 3.0 (8:92, v/v), delivered isocratically at a flow rate of 1.0 ml/min and at a column oven temperature of 30°C. Cefepime was used as an internal standard. Results: Linearity was achieved in the concentration range of 0.50–100.00 μg/ml for ceftolozane and 0.25–…

Multi-approach metabolomics analysis and artificial simplified phytocomplexes reveal cultivar-dependent synergy between polyphenols and ascorbic acid…

2017

Fruits of the sweet cherry (Prunus avium L.) accumulate a range of antioxidants that can help to prevent cardiovascular disease, inflammation and cancer. We tested the in vitro antioxidant activity of 18 sweet cherry cultivars collected from 12 farms in the protected geographical indication region of Marostica (Vicenza, Italy) during two growing seasons. Multiple targeted and untargeted metabolomics approaches (NMR, LC-MS, HPLC-DAD, HPLC-UV) as well as artificial simplified phytocomplexes representing the cultivars Sandra Tardiva, Sandra and Grace Star were then used to determine whether the total antioxidant activity reflected the additive effects of each compound or resulted from synergis…

2018

Chardonnay wines from Burgundy, obtained from musts with three levels of clarification (Low, Medium and High) during two consecutive vintages (2009 and 2010) and for two kinds of closures (screw caps and synthetic coextruded closures) were analyzed chemically and sensorially. Three bottles per turbidity level were opened in 2015 in order to assess the intensity of the reductive and/or oxidative aromas (REDOX sensory scores) by a trained sensory panel. The chemical analyses consisted in polyphenols and colloids quantification, followed by a proteomic characterization. For the two vintages, the REDOX sensory scores appeared to be driven both by the type of closure and to a lesser extent by th…

Chemical messages from an ancient buried bottle: Metabolomics for wine archeochemistry.

2017

Restoration works in the old Clunisian Saint-Vivant monastery in Burgundy revealed an unidentified wine bottle (SV1) dating between 1772 and 1860. Chemical evidence for SV1 origin and nature are presented here using non-targeted Fourier Transform Ion Cyclotron Resonance Mass Spectrometry and Nuclear Magnetic Resonance analyses. The SV1 chemical diversity was compared to red wines (Pinot Noir) from the Romanée Saint Vivant appellation and from six different vintages spanning from 1915 to 2009. The close metabolomic signature between SV1 and Romanée Saint Vivant wines spoke in favor of a filiation between these wines, in particular considering the Pinot noir grape variety. A further statistic…

Flavonoid determination in onion, chili and leek by hard cap espresso extraction and liquid chromatography with diode array detection

2018

Abstract A low cost extraction procedure, based on the use of a hard cap espresso machine, has been developed for the extraction of myricetin, quercetin, luteolin and kaempferol from vegetables by using 50 mL of ethanol in water (80% v/v) in

Development of a method to determine axitinib, lapatinib and afatinib in plasma by micellar liquid chromatography and validation by the European Medi…

2017

A method based on micellar liquid chromatography to quantify the tyrosine kinase inhibitors axitinib, lapatinib and afatinib in plasma is reported. The sample pretreatment was a simple 1/5-dilution in a pure micellar solution, filtration and direct injection, without requiring extraction or purification steps. The three drugs were resolved from the matrix in 17 min, using an aqueous solution of 0.07 M sodium dodecyl sulfate – 6.0% 1-pentanol, buffered at pH 7 with 0.01 M phosphate salt as mobile phase, running under isocratic mode at 1 mL/min through a C18 column. The detection was performed by absorbance at 260 nm. An accurate mathematical relationship was established between the retention…

A UHPLC-UV Method to Quantify Skin Deposition and Transdermal Permeation of Tizanidine Hydrochloride

2015

Tizanidine hydrochloride is an α2-adrenergic agonist used for the symptomatic relief of spasticity associated with multiple sclerosis or with spinal cord injury or disease. The objective of this study was to develop an isocratic, robust and sensitive ultra-high performance liquid chromatography method using UV detection for use in a project to develop a transdermal therapeutic system to deliver tizanidine across the skin. Isocratic separation was achieved using a C18 column and a mobile phase comprising a 80:20 mixture of 0.004% trifluoroacetic acid in water and MeCN (pH* 3.2) at a flow rate of 0.2 mL min(-1) Tizanidine eluted at 1.499 min and the total run time was 2 min. The method was sp…

Mineral profiles of legumes and fruits through partial least squares energy dispersive X-ray fluorescence

2019

Abstarct Energy dispersive X-ray fluorescence (ED-XRF) has been employed for the determination of mineral elements in 15 varieties of legumes and 14 cherry samples. ED-XRF signals directly obtained from pulverized samples were modelized by partial least squares (PLS) using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) of a selected number of samples, after microwave assisted acid digestion, as reference data. Models were built to predict the concentration of Al, Ca, Cu, Fe, K, Mg, P, Sr and Zn. Average concentrations predicted were 6, 930, 7, 40, 6400, 990, 2100, 4 and 15 μg g−1 for Al, Ca, Cu, Fe, K, Mg, P, Sr and Zn, respectively with relative errors from 7 till 26%. …