Search results for "cellar"

On the nature of the forces controlling selectivity in the high performance capillary electrochromatographic separation of peptides

2003

In this minireview, the nature of the forces controlling selectivity in the high performance capillary electrochromatographic (HP-CEC) separation of peptides has been examined. For uncharged and charged peptides, a synergistic interplay occurs in HP-CEC systems between adsorptive/partitioning events and electrokinetically driven motion. Moreover, at high field strengths, both bulk electrophoretic migration and surface electrodiffusion occur. Thus, the migration behavior of peptides in different HP-CEC systems can be rationalized in terms of the combined consequences of these various processes. Moreover, in HP-CEC, the buffer electrolyte interacts with both the peptide analytes and the sorbe…

Farmacovigilanza attiva sul ruolo dei farmaci antiangiogenetici nell’osteonecrosi dei mascellari

2013

Farmacovigilanza attiva sul ruolo dei farmaci antiangiogenetici nell’osteonecrosi dei mascellari Ilaria Morreale1, Maria Meli1, Olga Di Fede2, Giuseppina Campisi2, Natale D’Alessandro1 1Centro di consulenza sulle reazioni avverse da farmaci in oncologia della Regione Sicilia – U.O.C. di Farmacologia Clinica e 2Gruppo P.R.O.Ma.B. (Prevenzione e Ricerca sull’Osteonecrosi dei Mascellari da Bisfosfonati) - Settore di Medicina Orale "Valerio Margiotta" - AOUP “P. Giaccone” di Palermo Obiettivi L’uso dei bisfosfonati (BP) in oncologia e anche nell’osteoporosi è stato definitivamente associato ad una complicazione relativamente rara ma grave come l’osteonecrosi dei mascellari (ONJ). La patogenesi …

Raccomandazioni clinico-terapeutiche sull’osteonecrosi delle ossa mascellari associata a bisfosfonati e sua prevenzione

2013

Estimation of the effect of the acidosis and alkalosis on the anesthetic potency of local anesthetics by biopartitioning micellar chromatography and …

2004

Local anesthetics are hydrophobic compounds and weak bases with protonation constants ranged between 7.5 and 8.8. These drugs block reversibly nerve conduction near their site of application or injection and thus produce temporary loss of feeling or sensation in a limited area of the body. The efficacy of anesthetic blockade of local anesthetics depends on the charged/uncharged form ratio and the hydrophobicity of the compounds. In addition their toxicological effects have been reported to be highly dependent on the physiological pH. Biopartitioning micellar chromatography (BMC) and micellar electrokinetic chromatography (MEKC), that use micellar solutions as mobile phases, have proven to b…

Application of Organic Monolithic Materials to Enantioseparation in Capillary Separation Techniques.

2017

This review article is primarily focused on the state-of-the-art of enantioseparations on organic monolithic materials. The article gives an overview of the chiral stationary phases and its application in capillary electrochromatography (CEC), and capillary- and nano-liquid chromatography (cLC and nLC). Since thousands of publications have been emerged from 2000’s and citing all these papers would extend the scope of this review; then, recent developments from last 10 years (2006 to 2016) will be mentioned. Mostly, stationary phases based on copolymers obtained from chiral functional monomers and surface modifications of organic monoliths with chiral ligands will be discussed. The effective…

Retention-activity relationship studies of benzodiazepines by micellar liquid chromatography

1999

Solute partitioning into lipid bilayers of biological membranes is the basis for drug and metabolite uptake, passive transport across membranes and bioaccumulation. In order to emulate in vitro the partitioning process in the biomembranes, different approaches have been proposed. The use of micellar solutions as mobile phases in reversed-phase liquid chromatography (micellar liquid chromatography, MLC) has proven to be valid in the prediction of the biological activities of local anesthetics, catecholamines and barbiturates. In this paper we focus our attention on benzodiazepines. The retention of benzodiazepines using different concentrations of Brij35 as micellar mobile phase in modified …

Determination of phenobarbital in plasma by micellar liquid chromatography

2000

A new liquid chromatographic procedure for the determination of phenobarbital in plasma samples is described. The proposed system uses a Spherisorb octadecyl-silane ODS-2 C(18) analytical column, a guard column of similar characteristics, and a 0.03 M CTAB-3% 1-propanol at pH 7 mobile phase. The UV detector was set at 250 nm. Butabarbital was used as internal standard. Sample preparation only required the addition to the plasma samples of a 0.1 M SDS solution at pH 3 and centrifugation before injection into the chromatographic system. The limit of detection was 0.83 microg/mL of phenobarbital in plasma samples. The coefficients of variation were lower than 7. 5%.

Determination of amobarbital and secobarbital in plasma samples using micellar liquid chromatography

2000

A new liquid chromatographic procedure for the determination of amobarbital and secobarbital in plasma samples is proposed. The method uses a Spherisorb octadecylsilane ODS-2 C18 analytical column, a guard column of similar characteristics and 0.04 M CTAB solution buffered at pH 7.5 containing 3% 1-propanol as micellar mobile phase. The UV detection was carried out at 250 nm. Butabarbital was used as internal standard. Plasma samples preparation only required adequate dilution with the mobile phase before injection into the chromatographic system. The limits of detection were 0.2 and 0.4 mg/L for amobarbital and secobarbital, respectively. The proposed method allows the determination of amo…

An LD50model for predicting psychotropic drug toxicity using biopartitioning micellar chromatography

2001

The LD50 determination is the main way to measure the acute toxicity of all types of substances. At the present time, however, there is increasing opposition to the use of living animals in research and testing activities from animal rights groups as well as some scientists. Nevertheless, the need to have a tool for estimating the potential toxicity of new compounds for human consumption has encouraged the development of alternative methods. Under adequate conditions, the partitioning in micellar liquid chromatography can describe the drug biopartitioning. We have named this chromatographic system biopartitioning micellar chromatography (BMC). In this paper, an LD50 QRAR model developed for…

QRAR models for central nervous system drugs using biopartitioning micellar chromatography.

2002

The capability of biopartitioning Micellar Chromatography, BMC, to describe and estimate pharmacokinetic and pharmacodynamic parameters of central nervous system drugs is reviewed in this article. BMC is a mode of micellar liquid chromatography, MLC, that uses micellar mobile phases of Brij35 (polyoxyethilene(23) lauryl ether) prepared in physiological conditions (pH, ionic strength). The retention of a drug in this system depends on its hydrophobic, electronic and steric properties, which also determine its biological activity. The results of BMC studies suggest that this in vitro approach is an attractive useful tool to be implemented into the lead optimization step of drug development sc…