Search results for "performance"

Silver ion chromatography and gas chromatography-mass spectrometry in the structural analysis of cyclic dienoic acids formed in frying oils

1995

The nature of the cyclic monoenoic fatty acids formed from linoleic acid in sunflower oil heated to 275°C has been determined by gas chromatography-mass spectrometry of the picolinyl ester derivatives, before and after hydrogenation and deuteration, and following simplification by silver ion high-performance liquid chromatography. In addition, they were examined by gas chromatography-Fourier transform infrared spectroscopy. Cyclopentene fatty acids (50% of the total monoenes) were formed from C-8 to C-12 and C-10 to C-14 of the original chain in equal amounts with unique stereochemistry. In some isomers the double bond appeared to remain in its original position, and in others it migrated t…

Stability of tacrolimus ophthalmic solution

2017

Purpose The stability of 0.3-mg/mL tacrolimus ophthalmic solution at different storage temperatures was studied. Methods A sterile ophthalmic solution of 0.3 mg/mL tacrolimus was prepared in triplicate under aseptic conditions by diluting tacrolimus in eye drops. Three aliquots of this solution were transferred into polypropylene bottles and stored at 25, 2–8, or −15 to −25 °C. Samples were collected immediately after preparation and at selected time points and assayed in triplicate using high-performance liquid chromatography (HPLC). Samples were also visually examined for macroscopic changes. The 0.3-mg/mL tacrolimus solution was also exposed to acidic treatment and heat to force its degr…

Micellar electrokinetic capillary chromatography for therapeutic drug monitoring of carbamazepine and its main metabolites.

1998

In carbamazepine (CBZ) therapy the concomitant monitoring of concentrations of CBZ and its metabolites is strictly recommended, primarily to avoid toxic side effects. Currently, clinical routine monitoring of CBZ is accomplished by high-performance liquid chromatography or immunological methods. In this study a micellar electrokinetic capillary chromatographic (MECC) method was developed for routine drug monitoring of CBZ and its main metabolites, carbamazepine 10,11-diol and carbamazepine 10,11-epoxide, in human serum or plasma samples. The MECC method enabled baseline separation of all analytes within 2.5 min. The assay revealed sufficient precision and sensitivity and the results of eith…

Automated analysis of quetiapine and other antipsychotic drugs in human blood by high performance-liquid chromatography with column-switching and spe…

2004

Abstract An automated HPLC method with column switching is described for the determination of quetiapine, clozapine, perazine, olanzapine and metabolites in blood serum. After clean-up on silica C8 material (20 μm particle size) drugs were separated on ODS Hypersil C18 material (5 μm; column size 250 mm × 4.6 mm i.d.) within 25 min and quantified by ultraviolet (UV) detection at 254 nm. The limit of quantification ranged between 10 and 50 ng/ml. At therapeutic concentrations of the drugs, the inter-assay reproducibility was below 10%. Analyses of drug concentrations in serum of 75–295 patients treated with therapeutic doses of the antipsychotic drugs revealed mean ± S.D. steady state concen…

Comparison of Dialysis and Dispersion Methods for In Vitro Release Determination of Drugs from Multilamellar Liposomes

2008

The aim of these studies was to compare dialysis and dispersion methods for determining in vitro release of propranolol, metoprolol, pindolol, and atenolol from multilamellar liposomes. Multilamellar vesicles (MLV) were prepared using hydrogenated soy-lecithin phospholipon 90H (Ph 90H) as the primary lipid. The same volume of pH 7.4 phosphate buffered saline was used as a receptor medium for both methods. Samples were withdrawn, and drug concentration was determined using HPLC. All drug-containing liposomes exhibited an initial burst release followed by a slower rate of release. The rate and extent of drug release from MLV was dependent on the physicochemical properties of the drug. For all…

Therapeutic Monitoring of Aripiprazole by HPLC with Column-Switching and Spectrophotometric Detection

2005

Aripiprazole is a novel atypical antipsychotic drug for the treatment of schizophrenia and schizoaffective disorders (1)(2)(3). The drug is metabolized by the cytochrome P450 isoenzymes 3A4 and 2D6 (4). Because of high interindividual variability in the expression of these enzymes, the aripiprazole concentration varies among healthy individuals after administration of the drug (5). In patients, insufficient response or side effects, such as somnolence, akathisia, or nausea, may result from too low or too high drug concentrations. Therapeutic drug monitoring (TDM), which is established practice for many antipsychotic drugs (6)(7), may be helpful for patients treated with aripiprazole. We mea…

Multi-residue determination of 47 organic compounds in water, soil, sediment and fish—Turia River as case study

2017

A sensitive and reliable method based on solid-liquid extraction (SLE) using McIlvaine-Na2EDTA buffer (pH = 4.5)-methanol and solid-phase extraction (SPE) clean up prior to ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS) was applied to determine 47 organic contaminants in fish, soil and sediments. The SPE procedure to clean-up the extracts was also used as extraction method to determine these compounds in water. Recoveries ranged from 38 to 104% for all matrices with RSDs 50% for 36 compounds in front of 9, matrix effect < 20% for 31 compounds against 21, and LOQs <25 ng g−1 for 38 compounds against 22) indicates that the proposed method is mor…

Overcoming traditional Performance Management in Public Healthcare Institutions: The need for a DPM Approach

Donabedian (1988) was the scientific father of the notion that Performance Measurement (PM) of hospital outputs leads to improved quality of healthcare services, setting the foundations of how hospital quality is still today defined, considered and measured using three different kinds of measures: structure, process and outcome measures. Nonetheless, a growing part of literature during the last two decades has started doubting those favourable outcomes of PM on hospital quality (De Vos, et al., 2009; Nolan &amp; Berwick, 2006; Werner et al., 2008a, 2008b; Werner &amp; Bradlow, 2006; Wright &amp; Hershman, 2014) while other research shows that ineffective PM systems are not just useless but …

POLICY INNOVATION AND IMPLEMENTATION IN PUBLIC SECTOR: COMPLEXITIES, DYNAMICS AND UNCERTAINTIES

This research is expected to contribute to the knowledge base on how an effective impact assessment and adoption of innovations in the public sector could be facilitated. The need for trans-disciplinary assessment of the long-term potential impacts of innovation-driven policies may well be met with system dynamics as part of the dynamic performance management approach by way of modelling based simulation and analysis. Moreover, such analysis may contribute to learning and the accumulation of a knowledge repository that enables strategy developers, policy designers and decision makers to arrive at unexpected (often called counterintuitive) conclusions prior to policy implementation. Such ins…

SIMULATION AND EXPERIMENTAL METHODS FOR IMPROVING ENERGY EFFICIENCY, ENVIRONMENTAL PERFORMANCE AND RESILIENCE OF SINGLE AND CLUSTERED GROUPS OF BUILD…

2021

Energy consumption in the building sector is responsible for 36% of the energy use worldwide (corresponding to 39% of the total energy-related CO2 emissions), while at the European level the building sector accounts for a share of the total energy consumption comprised between 25% and 40% (corresponding to about 35% of the overall CO2 emissions throughout Europe). Concerning the Italian context, instead, such figures stand at about 40% and 17.5% for the energy consumption and for the CO2 emissions, respectively. In light of this, much attention has been paid, at global, European and single countries (national) levels on the important aspects regarding the reduction of energy consumption and…